Basic Statistics for Business and Economics 10th Edition by Douglas A. Lind. TEST BANK

CHAPTER 1 1)

Which of the following is not an example of a statistic?

A) The weekly income of the typical high school graduate compared to a typical college graduate B) A list of the profits earned last year for 100 companies in the United States C) The unemployment rate in the United States for last month D) The average profit earned last year for the 10 top companies on the Dow Jones Index

2) A store asks shoppers for their zip codes to identify market areas. Zip codes are an example of ratio data. ⊚ true ⊚ false

3) What type of variable is the number of gallons of gasoline pumped by a filling station during a day?

A) Discrete B) Qualitative C) Attribute D) Continuous

4)

The incomes of 50 loan applicants are obtained. Which level of measurement is income?

A) Interval B) Ratio C) Ordinal D) Nominal

5)

An example of a qualitative variable is

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A) miles between oil changes.

B) number of children in a family.

C) weight of a person.

D) color of ink in a pen.

6)

SAT scores are an example of ratio data. ⊚ true ⊚ false

7)

Statistics is used to report the summary results of market surveys. ⊚ true ⊚ false

8) When TV advertisements report that "2 out of 3 dentists surveyed indicated they would recommend Brand X toothpaste to their patients," an informed consumer may question the conclusion because A) the conclusion is not illustrated with a graph.

B) the sample of dentists is clearly explained.

C) the advertisement does not include the total number of dentists surveyed.

D) the sample was only 5 dentists.

9)

The terms descriptive statistics and inferential statistics can be used interchangeably. ⊚ true ⊚ false

10) The average number of passengers on commercial flights between Chicago and New York City is an example of a statistic.

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11)

true false

The main purpose of descriptive statistics is to A) gather or collect data.

B) make inferences about a population.

C) determine if the data adequately represent the population.

D) summarize data in a useful and informative manner.

12)

The ordinal level of measurement is considered the "lowest" level of measurement. ⊚ true ⊚ false

13) If we select 100 persons from 25,000 registered voters and question them about candidates and issues, the 100 persons are referred to as the population. ⊚ true ⊚ false

14) The monthly average number of cases of people testing positive for a virus infection, by country, is an example of a statistic. ⊚ true ⊚ false

15) The CIA World Factbook cited these numbers for the United States: ● The birthrate is 13.66 births per 1,000 of the population. ● The average life expectancy for females is 81.17 years. ● Approximately 316.7 million persons reside in the United States.

Each of these numbers is referred to as a statistic.

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true false

16) Based on a sample of 3,000 people, the civilian unemployment rate in the United States was 5.5%. The 5.5% is referred to as a statistic. ⊚ true ⊚ false

17) The Nielsen Ratings break down the number of people watching a particular television show by age. What level of measurement is age?

A) Ratio B) Nominal C) Interval D) Ordinal

18)

Which word is not part of the definition of descriptive statistics?

A) Predicting B) Presenting C) Organizing D) Summarizing

19)

A portion or part of a population is called a A) frequency distribution.

B) random survey.

C) tally.

D) sample.

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20)

Credit rating scores are an example of interval data. ⊚ true ⊚ false

21) When statisticians analyze sample data in order to draw conclusions about the characteristics of a population, this is referred to as A) data summarization.

B) statistical inference.

C) data analysis.

D) descriptive statistics.

22) The members of each basketball team wear numbers on their jerseys. What scale of measurement are these numbers considered?

A) Ordinal B) Nominal C) Ratio D) Interval

23)

The length of a bridge, measured in meters, is an example of A) qualitative data.

B) measurement data.

C) either qualitative or categorical data.

D) quantitative data.

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24) A marketing class of 50 students evaluated the instructor using the following scale: superior, good, average, poor, or inferior. The descriptive summary showed the following survey results: 2% superior, 8% good, 45% average, 45% poor, and 0% inferior.

A) The instructor's performance was great!

B) The instructor's performance was inferior.

C) No conclusions can be made.

D) Most students rated the instructor as poor or average.

25)

Which of the following is an example of a continuous variable?

A) Tons of concrete to complete a parking garage B) Zip codes of shoppers C) Number of students in a statistics class D) Rankings of baseball teams in a league

26)

An ordinal level of measurement implies some sort of ranking. ⊚ true ⊚ false

27)

Which of the following is true?

A) Statistics is never required to make personal decisions.

B) Data is collected and analyzed for you by computer programs, so there is no need to understand statistics.

C) Statistical techniques are only useful for certain professions.

D) No matter what your career, you need a knowledge of statistics to understand the world.

28)

The number of children in a family is a discrete variable.

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29)

true false

The order in which runners finish in a race would be an example of continuous data. ⊚ true ⊚ false

30) The general process of gathering, organizing, summarizing, analyzing, and interpreting data is called A) levels of measurement.

B) descriptive statistics.

C) inferential statistics.

D) statistics.

31) The names of the positions in a corporation, such as chief operating officer or controller, are examples of what type of variable?

A) Quantitative B) Ratio C) Qualitative D) Interval

32)

To infer something about a population, we usually take a sample from the population. ⊚ true ⊚ false

33) Descriptive statistics are used to find out something about a population based on a sample.

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34)

true false

What level of measurement is a person's "favorite sport"?

A) Ratio B) Ordinal C) Nominal D) Interval

35) Income is a variable often used in business and economics. Income is an example of a variable that uses the A) ordinal scale.

B) nominal scale.

C) interval scale.

D) ratio scale.

36) The branch of mathematics used to facilitate the collection, organization, presentation, analysis, and interpretation of numerical information is referred to as statistics. ⊚ true ⊚ false

37) A bank asks customers to evaluate its drive-through service as good, average, or poor.

Which level of measurement is this classification?

A) Ordinal B) Ratio C) Nominal D) Interval

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38) A university wishes to conduct a student survey. In one of the questions, students are asked to mark their gender as either male or female. Gender is an example of the A) ordinal scale.

B) nominal scale.

C) interval scale.

D) ratio scale.

39) Statistics is defined as a body of techniques used to facilitate the collection, organization, presentation, analysis, and interpretation of information for the purpose of making better decisions. ⊚ true ⊚ false

40)

A population is a collection of all individuals, objects, or measurements of interest. ⊚ true ⊚ false

41) A group of women tried five brands of fingernail polish and ranked them according to preference. What level of measurement is this?

A) Interval B) Nominal C) Ordinal D) Ratio

42)

The American Statistical Association

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A) has no approved ethical standards for statisticians.

B) encourages statisticians to mislead people when reporting findings and results.

C) advises statisticians to “lie with statistics.”

D) has guidelines which advise statisticians to maintain ethical standards.

43) A pharmaceutical company evaluates a new vaccine's effectiveness as excellent, good, average, or low. Which level of measurement is this classification?

A) Interval B) Ratio C) Nominal D) Ordinal

44)

Shoe style is an example of what level of measurement?

A) Interval B) Ordinal C) Ratio D) Nominal

45) The Equal Employment Opportunity Act requires employers to classify their employees by gender and national origin. Which level of measurement is this?

A) Nominal B) Interval C) Ratio D) Ordinal

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46) A marketing research agency was hired to test a new smartphone. Consumers rated it outstanding, very good, fair, or poor. The level of measurement for this experiment is ordinal. ⊚ true ⊚ false

47)

What type of variable is the number of auto accidents reported in a given month?

A) Continuous B) Discrete C) Ratio D) Interval

48)

What type of variable is the number of robberies reported in your city?

A) Attribute B) Quantitative C) Qualitative D) Continuous

49) Respondents were asked, "Do you now earn more than or less than you did five years ago?" What is this level of measurement?

A) Interval B) Ratio C) Nominal D) Ordinal

50)

Your height and weight are examples of which level of measurement?

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A) Interval B) Ordinal C) Ratio D) Nominal

51) The Union of Electrical Workers of America with 9,128 members polled 362 members about a new wage package that will be submitted to management. The population is the 362 members. ⊚ true ⊚ false

52) The principal difference between the interval and ratio scale is that the ratio scale has a meaningful zero point. ⊚ true ⊚ false

53)

Ethical statisticians

A) withhold information that does not support favored conclusions.

B) ensure that statistical reports and conclusions match desired findings even if the data do not support this.

C) use honesty and integrity when summarizing, analyzing, and interpreting data.

D) never mention any limitations of statistical analysis or possible sources of error when presenting reports.

54)

There are four levels of measurement: qualitative, quantitative, discrete, and continuous. ⊚ true ⊚ false

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55) When pharmaceutical companies try a new vaccine on a portion or part of a population, this is called a: A) sample.

B) random survey.

C) frequency survey.

D) tally.

56)

A sample is a portion or part of the population of interest. ⊚ true ⊚ false

57) The final rankings of the top 20 NCAA college basketball teams are an example of which level of measurement?

A) Nominal B) Interval C) Ratio D) Ordinal

58)

Data measured on a nominal scale can only be classified into categories. ⊚ true ⊚ false

59)

What type of variable is "pounds of popcorn" served at a movie theater?

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A) Interval B) Ratio C) Discrete D) Continuous

60) If Gallup, Harris, and other pollsters asked people to indicate their political party affiliations as Democrat, Republican, or Independent, the data gathered would be an example of which scale of measurement?

A) Nominal B) Ordinal C) Interval D) Ratio

61)

Which one of the following is not an example of discrete data?

A) Number of members of the Denver Lions Club B) Number of households watching the Home Shopping Network C) Number of miles between New York City and Chicago D) Number of employees reporting in sick

62)

A listing of 100 family annual incomes is an example of statistics. ⊚ true ⊚ false

63) A survey includes a question about marital status that has the following responses: single, married, divorced, separated, or widowed. What is the level of measurement for this question?

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A) Ratio B) Ordinal C) Nominal D) Interval

64)

Which of the following is an example of a qualitative variable?

A) The industry category that a company is in B) The share prices of company stocks C) The percent change in stock price D) The stock volume of shares sold

65) Categorizing voters as Democrats, Republicans, and Independents is an example of interval level measurement. ⊚ true ⊚ false

66) The performance of personal and business investments is measured as a percentage called "return on investment." What type of variable is "return on investment"?

A) Qualitative B) Continuous C) Attribute D) Discrete

67)

What level of measurement is the Centigrade temperature scale?

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A) Nominal B) Ratio C) Ordinal D) Interval

68)

Statistics are used as a basis for making decisions. ⊚ true ⊚ false

69) The reported unemployment is 5.5% of the population. What level of measurement is used to measure unemployment?

A) Ordinal B) Ratio C) Interval D) Nominal

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Answer Key Test name: Chap 01_10e_Lind 1) B 2) FALSE 3) D 4) B 5) D 6) FALSE 7) TRUE 8) C 9) FALSE 10) TRUE 11) D 12) FALSE 13) FALSE 14) TRUE 15) TRUE 16) TRUE 17) A 18) A 19) D 20) TRUE 21) B 22) B 23) D 24) D 25) A 26) TRUE Version 1

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27) D 28) TRUE 29) FALSE 30) D 31) C 32) TRUE 33) FALSE 34) C 35) D 36) TRUE 37) A 38) B 39) TRUE 40) TRUE 41) C 42) D 43) D 44) D 45) A 46) TRUE 47) B 48) B 49) C 50) C 51) FALSE 52) TRUE 53) C 54) FALSE 55) A 56) TRUE Version 1

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57) D 58) TRUE 59) D 60) A 61) C 62) FALSE 63) C 64) A 65) FALSE 66) B 67) D 68) TRUE 69) B

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CHAPTER 2 1) For the following distribution of heights, what are the limits for the class with the greatest frequency?

Heights Frequency

60" up to 65" 10

65" up to 70" 70

70" up to 75" 20

A) 69.5 and 74.5 B) 65 and up to 70 C) 65 and 69 D) 64 and up to 70

2) Refer to the following frequency distribution of days absent during a calendar year by employees of a manufacturing company: Days Absent 0 up to 3 3 up to 6 6 up to 9 9 up to 12 12 up to 15

Number of Employees 4 39 45 51 22

How many employees were absent six or more days?

A) 118 B) 49 C) 39 D) 73

3) Refer to the following breakdown of responses to a survey of "How confident are you that you saved enough to retire?"

Response Very confident

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Frequency 63

1

Somewhat confident Not very confident Don't know

135 99 3

What is the class with the greatest frequency?

A) Not very confident B) Somewhat confident C) Don't know D) Very confident

4)

Refer to the following distribution: Cost of Textbooks $45 up to $55 55 up to 65 65 up to 75 75 up to 85 85 up to 95

Frequency 2 5 7 20 16

What is the class midpoint for the $65 up to $75 class?

A) $70.50 B) $69.00 C) $69.50 D) $70.00

5)

A pie chart shows the relative frequency in each class. ⊚ true ⊚ false

6) When establishing the beginning point of a histogram, if your smallest value is 308 and your largest value is 4396, and you have 55 values, a good place to start your graph would be

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A) 305.

B) 308.

C) 400.

D) 300.

7) Refer to the following breakdown of responses to a survey of "Are you concerned about being tracked while connected to the Internet?"

Response Very concerned Somewhat concerned No concern

Frequency 140 40 20

What type of chart should be used to describe the frequency table?

A) A bar chart B) A pie chart C) A histogram D) A frequency polygon

8) Monthly commissions of first-year insurance brokers are $1,270, $1,310, $1,680, $1,380, $1,410, $1,570, $1,180, and $1,420. These figures are referred to as A) a frequency distribution.

B) a histogram.

C) raw data.

D) a frequency polygon.

9) Refer to the following breakdown of responses to a survey of "How confident are you that you saved enough to retire?": Response

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Frequency 3

Very confident Somewhat confident Not very confident Don't know

63 135 99 3

What percentage of the responses indicated that users were very confident?

A) 45% B) 33% C) 21% D) 63%

10) Refer to the following breakdown of responses to a survey of "Are you concerned about being tracked while connected to the Internet?": Response Very concerned Somewhat concerned No concern

Frequency 140 40 20

What percentage of the responses indicated that users were somewhat concerned?

A) 70% B) 20% C) 40% D) 100%

11)

Refer to the following distribution of ages.

Ages 40 up to 50 50 up to 60 60 up to 70

Frequency 10 28 12

For this distribution of ages, what is the relative class frequency for the lowest class?

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A) 0.50 B) 0.18 C) 0.10 D) 0.20

12)

Which of the following statements about histograms are true?

A) The heights of the bars represent relative class frequencies.

B) A histogram has gaps between the bars.

C) A histogram is used to display qualitative data.

D) The bars are drawn adjacent to each other because the data is continuous.

13)

Refer to the following breakdown of responses to a survey of room service in a hotel.

Response Not satisfied Satisfied Highly satisfied

Frequency 20 40 60

What is the class with the greatest frequency?

A) Highly satisfied B) None apply C) Satisfied D) Not satisfied

14)

Refer to the following distribution:

Cost of Textbooks $25 up to $35 35 up to 45 45 up to 55

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Frequency 2 5 7 5

55 up to 65 65 up to 75

20 16

What is the class midpoint for the $45 up to $55 class?

A) $49 B) $49.5 C) $50.5 D) $50

15)

A pie chart shows the A) B) C) D)

frequencies of a ratio variable. relative frequencies of a quantitative variable. frequencies of a nominal variable. relative frequencies of a qualitative variable.

16) Refer to the following frequency distribution of days absent during a calendar year by employees of a manufacturing company: Days Absent 0 up to 3 3 up to 6 6 up to 9 9 up to 12 12 up to 15

Number of Employees 14 49 58 28 6

How many employees were absent for 3 up to 6 days?

A) 58 B) 6 C) 49 D) 73

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17)

Why are unequal class intervals sometimes used in a frequency distribution?

A) To avoid a large number of classes with very small frequencies B) To avoid the need for midpoints C) For the sake of variety in presenting the data D) To make the class frequencies smaller

18)

Which of the following statements about frequency polygons are true?

A) A frequency polygon is a graph of a bar chart.

B) Frequency polygons represent each class as a rectangle.

C) The frequencies of each class are graphed at the midpoint of each class.

D) Frequency polygons do not show the shape of a distribution.

19)

Refer to the following distribution of ages.

Ages 40 up to 50 50 up to 60 60 up to 70

Frequency 10 28 12

What is the class interval?

A) 10 B) 9 C) 10.5 D) 11

20) Refer to the following information from a frequency distribution for heights of college women recorded to the nearest inch: the first two class midpoints are 62.5" and 65.5". What are the class limits for the third class?

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A) 66" and 68" B) 64" and up to 67" C) 67" and up to 70" D) 67" and 69"

21) A group of 100 students were surveyed about their interest in a new Economics major.

Interest was measured in terms of high, medium, or low. In the study, 30 students responded high interest, 50 students responded medium interest, and 20 students responded low interest. What is the best way to illustrate the relative frequency of student interest?

A) Use a frequency table.

B) Use a box plot.

C) Use a cumulative frequency polygon.

D) Use a pie chart.

22)

The midpoint of a class is halfway between the lower and upper limits. ⊚ true ⊚ false

23) In a bar chart, the horizontal axis is usually labeled with the values of a qualitative variable. ⊚ true ⊚ false

24) A group of 100 students was surveyed about their interest in a new International Studies program. Interest was measured in terms of high, medium, or low. In the study, 30 students responded high interest, 40 students responded medium interest, and 30 students responded low interest. What is the relative frequency of students with high interest?

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A) 0.50 B) 0.40 C) 0.30 D) 0.030

25) Refer to the following breakdown of responses to a survey of "Are you concerned about being tracked while connected to the Internet?": Response Very concerned Somewhat concerned No concern

Frequency 100 40 120

What percentage of the responses indicated that users were somewhat concerned?

A) 100% B) 15% C) 40% D) 50%

26) A table summarizing a set of data showing the fraction of the total number of items in several classes is a A) relative frequency table.

B) frequency table.

C) cumulative frequency table.

D) normal frequency table.

27) A small sample of computer operators shows monthly incomes of $1,950, $1,775, $2,060, $1,840, $1,795, $1,890, $1,925, and $1,810. What are these ungrouped numbers called?

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A) Histograms B) Raw data C) Class frequencies D) Class limits

28)

Refer to the following breakdown of responses to a survey of room service in a hotel.

Response Not satisfied Satisfied Highly satisfied

Frequency 20 40 60

What type of chart should be used to describe the frequency table?

A) A histogram B) A bar chart C) A frequency polygon D) A pie chart

29) Refer to the following breakdown of responses to a survey of "How confident are you that you saved enough to retire?"

Response Very confident Somewhat confident Not very confident Don't know

Frequency 63 135 99 3

What type of chart should be used to show relative class frequencies?

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A) A bar chart B) A frequency polygon C) A pie chart D) A histogram

30)

In a frequency distribution, the number of observations in a class is called the class A) midpoint.

B) array.

C) frequency.

D) interval.

31)

When a class interval is expressed as 100 up to 200, A) observations with values of 200 are excluded from the class.

B) observations with values of 200 are included in the class.

C) the class interval is 99.

D) observations with values of 100 are excluded from the class.

32) Refer to the following breakdown of responses to a survey of "How confident are you that you saved enough to retire?"

Response Very confident Somewhat confident Not very confident Don't know

Frequency 63 135 99 3

What type of chart should be used to describe the frequency table?

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A) A histogram B) A pie chart C) A bar chart D) A frequency polygon

33) pie.

To construct a pie chart, relative class frequencies are used to graph the "slices" of the ⊚ ⊚

34)

true false

What is the difference between a histogram and a bar chart?

A) There is no difference. Histograms and bar charts are interchangeable.

B) Histograms have distinct gaps between the bars and bar charts have no gaps between the bars.

C) A histogram is used to display quantitative data and a bar chart is used to display qualitative data.

D) Histograms are used to display categorical data, while bar charts are used to display numerical data.

35)

Refer to the following breakdown of responses to a survey of room service in a hotel:

Response Not satisfied Satisfied Highly satisfied

Frequency 50 30 60

What percentage of the responses indicated that customers were satisfied?

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A) 21% B) 100% C) 43% D) 30%

36)

Refer to the following distribution:

Cost of Textbooks $25 up to $35 35 up to 45 45 up to 55 55 up to 65 65 up to 75

Frequency 3 5 6 17 19

What are the class limits for the class with the highest frequency?

A) $65 up to $74.5 B) $65 up to $75 C) $64 up to $74 D) $65 up to $74

37)

For a relative frequency distribution, relative frequency is computed as A) the class width divided by the class interval.

B) the class frequency divided by the class interval.

C) the class midpoint divided by the class frequency.

D) the class frequency divided by the number of observations.

38)

Refer to the following distribution of commissions.

Monthly Commissions $600 up to $800

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Class Frequencies 3 13

800 up to 1,000 1,000 up to 1,200 1,200 up to 1,400 1,400 up to 1,600 1,600 up to 1,800 1,800 up to 2,000 2,000 up to 2,200

7 11 12 40 24 9 4

What is the relative frequency for salespeople who earn from $1,600 up to $1,800?

A) 0.20 B) 0.02 C) 0.24 D) 0.024

39)

Which of the following statements about frequency polygons are FALSE?

A) A frequency polygon is a graph of a frequency distribution.

B) Frequency polygons allow us to directly compare two or more frequency distributions.

C) Frequency polygons do not show the shape of a distribution.

D) The frequencies of each class are graphed at the midpoint of each class.

40) Refer to the following breakdown of responses to a survey of "How confident are you that you saved enough to retire?": Response Very confident Somewhat confident Not very confident Don't know

Frequency 75 13 78 134

What percentage of the responses indicated that users were very confident?

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A) 25% B) 75% C) 4% D) 37%

41) A student was studying the political party preferences of a university's student population. The survey instrument asked students to identify themselves as a Democrat or a Republican. This question is flawed because A) political preference is a continuous variable.

B) political preference is a continuous variable.

C) the categories are generally mutually exclusive.

D) the categories are not exhaustive.

E) students generally don't know their political preferences.

42) Refer to the following information from a frequency distribution for heights of college women recorded to the nearest inch: the first two class midpoints are 62.5" and 65.5". What are the class limits for the lowest class?

A) 62" and up to 64" B) 61" and up to 64" C) 62" and 65" D) 62" and 63"

43)

In a bar chart, the heights of the bars represent the frequencies in each class. ⊚ true ⊚ false

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44) Refer to the following breakdown of responses to a survey of "Are you concerned about being tracked while connected to the Internet?"

Response Very concerned Somewhat concerned No concern

Frequency 140 40 20

What type of chart should be used to show relative class frequencies?

A) A bar chart B) A frequency polygon C) A histogram D) A pie chart

45) When data are collected using a qualitative, nominal variable, what is true about a frequency table that summarizes the data?

A) A pie chart can be used to summarize the data.

B) The number of classes is equal to the number of variable's values plus 2.

C) The upper and lower class limits must be calculated.

D) The "5 to the k rule" can be applied.

46) Refer to the following frequency distribution of days absent during a calendar year by employees of a manufacturing company: Days Absent 0 up to 3 3 up to 6 6 up to 9 9 up to 12 12 up to 15

Number of Employees 60 31 14 6 2

How many employees were absent fewer than six days?

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A) 31 B) 60 C) 91 D) 46

47) To convert a frequency distribution to a relative frequency distribution, divide each class frequency by the number of classes. ⊚ true ⊚ false

48) Refer to the following breakdown of responses to a survey of "Are you concerned about being tracked while connected to the Internet?"

Response Very concerned Somewhat concerned No concern

Frequency 140 40 20

What is the class interval for the preceding frequency table?

A) 40 B) 20 C) None apply D) 10

49) Refer to the following information from a frequency distribution for heights of college women recorded to the nearest inch: the first two class midpoints are 62.5" and 65.5". What is the class interval?

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A) 2" B) 2.5" C) 3" D) 1"

50) After using the “2 to the kth” rule, it suggests that your graph have 9 classes. However, you decide to use 10 classes instead of 9. Your decision to use 10 classes causes the class interval to be larger. ⊚ true ⊚ false

51)

Refer to the following breakdown of responses to a survey of room service in a hotel.

Response Not satisfied Satisfied Highly satisfied

Frequency 20 40 60

What type of chart should be used to show relative class frequencies?

A) A frequency polygon B) A bar chart C) A pie chart D) A histogram

52) Assume that you have 55 data points, and a “2 to the k rule” table looks like the following: k 1 2 3

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18

4 5 6 7 8

16 32 64 128 256

How many classes, or bars should you consider having for your frequency diagram?

A) 10 B) 50 C) 12 D) 6

53) Refer to the following information from a frequency distribution for heights of college women recorded to the nearest inch: the first two class midpoints are 80.5" and 83.5". What are the class limits for the lowest class?

A) 80" and 83" B) 80" and 81" C) 80" and up to 82" D) 79" and up to 82"

54)

Refer to the following breakdown of responses to a survey of room service in a hotel:

Response Not satisfied Satisfied Highly satisfied

Frequency 20 40 60

What percentage of the responses indicated that customers were satisfied?

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A) 100% B) 33% C) 50% D) 40%

55)

Refer to the following distribution:

Cost of Textbooks $25 up to $35 35 up to 45 45 up to 55 55 up to 65 65 up to 75

Frequency 2 5 7 20 16

What are the class limits for the class with the highest frequency?

A) $55 up to $64.5 B) $54 up to $64 C) $55 up to $64 D) $55 up to $65

56) Refer to the following frequency distribution of days absent during a calendar year by employees of a manufacturing company: Days Absent 0 up to 3 3 up to 6 6 up to 9 9 up to 12 12 up to 15

Number of Employees 60 31 14 6 2

How many employees were absent six or more days?

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A) 8 B) 4 C) 31 D) 22

57) The monthly salaries of a sample of 100 employees were rounded to the nearest $10.

They ranged from a low of $1,040 to a high of $1,720. If we want to condense the data into seven classes, what is the most convenient class interval?

A) $50 B) $200 C) $150 D) $100

58) When constructing frequency distributions for continuous quantitative data, the first thing to determine is A) the number of classes.

B) the individual class limits.

C) the class interval.

D) the number of observations in each class.

59)

Refer to the following wage breakdown for a garment factory.

Hourly Wages $4 up to $7 7 up to 10 10 up to 13 13 up to 16

Number of Employees 18 36 20 6

What is the class interval for the preceding table of wages?

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A) $4 B) $3 C) $5 D) $2

60) A frequency polygon is a very useful graphic technique when comparing two or more distributions. ⊚ true ⊚ false

61)

Refer to the following wage breakdown for a garment factory.

Hourly Wages $4 up to $7 7 up to 10 10 up to 13 13 up to 16

Number of Employees 18 36 20 6

What are the class limits for the class with the smallest frequency?

A) 3.5 and 6.5 B) 13 and up to 16 C) 4 and up to 7 D) 12.5 and 15.5

62)

A pie chart is similar to a relative frequency distribution. ⊚ true ⊚ false

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63)

Refer to the following distribution of ages.

Ages 40 up to 50 50 up to 60 60 up to 70

Frequency 10 28 12

What is the class midpoint of the highest class?

A) 55 B) 55 C) 65 D) 65 E) 54 F) 64 G) 64

64)

Refer to the following distribution of commissions.

Monthly Commissions $600 up to $800 800 up to 1,000 1,000 up to 1,200 1,200 up to 1,400 1,400 up to 1,600 1,600 up to 1,800 1,800 up to 2,000 2,000 up to 2,200

Class Frequencies 3 7 11 12 40 24 9 4

For the preceding distribution, what is the midpoint of the class with the greatest frequency?

A) 1,700 B) 1,500 C) The midpoint cannot be determined.

D) 1,400

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65) In frequency distributions, classes are mutually exclusive if each individual, object, or measurement is included in only one category. ⊚ true ⊚ false

66)

A frequency table for qualitative data has class limits. ⊚ true ⊚ false

67) A student was studying the political party preferences of a university's student population. The survey instrument asked students to identify their political preferences—for example, Democrat, Republican, Libertarian, or another party. The best way to illustrate the relative frequency distribution is a A) histogram.

B) bar chart.

C) pie chart.

D) frequency polygon.

68) A student was interested in the cigarette-smoking habits of college students and collected data from an unbiased random sample of students. The data are summarized in the following table.

Males who smoke Males who do not smoke Females who smoke Females who do not smoke

20 30 25 50

What type of chart would best represent the data from this frequency table?

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A) Frequency polygon B) Scatterplot C) Bar chart D) Box plot

69)

In constructing a frequency distribution, the approximate class interval is computed as A) (maximum value − minimum value)/(number of classes).

B) (maximum value)/(number of classes− sample size).

C) (minimum value− maximum value)/(sample size).

D) (maximum value− minimum value)/(sample size).

70) Refer to the following frequency distribution of days absent during a calendar year by employees of a manufacturing company: Days Absent 0 up to 3 3 up to 6 6 up to 9 9 up to 12 12 up to 15

Number of Employees 60 31 14 6 2

How many employees were absent for 6 up to 12 days?

A) 12 B) 8 C) 20 D) 17

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71) A student was interested in the cigarette-smoking habits of college students and collected data from an unbiased random sample of students. The data are summarized in the following table.

Males who smoke Males who do not smoke Females who smoke Females who do not smoke

20 30 25 50

What type of chart best represents the relative class frequencies?

A) Frequency polygon B) Scatterplot C) Box plot D) Pie chart

72)

Which of the following statements about histograms are true?

A) A histogram has gaps between the bars.

B) The heights of the bars represent class frequencies.

C) Histograms are used to display discrete numerical data.

D) Histograms are used to display qualitative, categorical data.

E) The heights of the bars represent class frequencies.

F) A histogram has gaps between the bars.

G) Histograms are used to display qualitative, categorical data.

73)

The “2 to the k rule” is used A) to determine the category width.

B) to determine the number of classes for graphing continuous data.

C) to quickly count the number of observations in each category D) to determine the lowest category value on a graph.

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74) To convert a frequency distribution to a relative frequency distribution, divide each class frequency by the sum of the class frequencies. ⊚ true ⊚ false

75)

What is the following table called?

Ages 20 up to 30 30 up to 40 40 up to 50 50 up to 60 60 up to 70 70 up to 80

Number of Ages 16 25 51 80 20 8

A) Cumulative frequency distribution B) Histogram C) Frequency polygon D) Frequency distribution

76)

The relative frequency for a class represents the A) percentage of observations in the class.

B) class width.

C) class interval.

D) class midpoint.

77)

Refer to the following distribution:

Cost of Textbooks $25 up to $35

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Frequency 15

27

35 up to 45 45 up to 55 55 up to 65 65 up to 75

10 13 5 17

What is the relative class frequency for the $25 up to $35 class?

A) 0.23 B) 0.26 C) 0.25 D) 0.31

78)

Refer to the following wage breakdown for a garment factory.

Hourly Wages $4 up to $7 7 up to 10 10 up to 13 13 up to 16

Number of Employees 18 36 20 6

What is the class midpoint for the class with the greatest frequency?

A) $5.50 B) $8.50 C) $11.50 D) $14.50

79) A class interval can be determined by subtracting the lower limit of a class from the lower limit of the next higher class. ⊚ true ⊚ false

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80) A cumulative frequency distribution is used when we want to determine how many observations lie above or below certain values. ⊚ true ⊚ false

81)

Refer to the following distribution of commissions.

Monthly Commissions $600 up to $800 800 up to 1,000 1,000 up to 1,200 1,200 up to 1,400 1,400 up to 1,600 1,600 up to 1,800 1,800 up to 2,000 2,000 up to 2,200

Class Frequencies 3 7 11 12 40 24 9 4

To plot a cumulative frequency distribution, the first coordinate would be A) X = 600, Y = 0.

B) X = 500, Y = 3.

C) X = 0, Y = 600.

D) X = 3, Y = 600.

82) Refer to the following frequency distribution of days absent during a calendar year by employees of a manufacturing company: Days Absent 0 up to 3 3 up to 6 6 up to 9 9 up to 12 12 up to 15

Number of Employees 60 31 14 6 2

How many employees were absent for 3 up to 6 days?

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A) 14 B) 31 C) 2 D) 29

83)

In order to convert class frequency to relative class frequency, we A) divide the sample size by the frequency of the class.

B) divide the midpoint of the class by the sample size.

C) divide the frequency of the class by the sample size.

D) divide the frequency of the class by the midpoint.

84) Refer to the following breakdown of responses to a survey of "How confident are you that you saved enough to retire?"

Response Very confident Somewhat confident Not very confident Don't know

Frequency 63 135 99 3

What is the class interval for the preceding frequency table?

A) None apply B) 40 C) 20 D) 10

85) A frequency distribution is a grouping of quantitative data into overlapping classes showing the number of observations in each class.

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⊚ ⊚

86)

true false

Here is a sample distribution of hourly earnings in Paul's Cookie Factory.

Hourly Earning Frequency

$6 up to $9 16

$9 up to $12 42

$12 up to $15 10

The limits of the class with the smallest frequency are A) $12.00 and up to $14.00.

B) $11.75 and $14.25.

C) $6.00 and $9.00.

D) $12.00 and up to $15.00.

87) When establishing a category width, assume that you have 55 raw data values, that you have determined to use 6 classes, the largest data value is 4396, and the smallest data value is 308. What class interval would you use?

A) 700 B) 681 C) 450 D) 680

88)

Refer to the following distribution of commissions.

Monthly Commissions $600 up to $800 800 up to 1,000 1,000 up to 1,200 1,200 up to 1,400 1,400 up to 1,600 1,600 up to 1,800

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Class Frequencies 3 7 11 22 40 24

31

1,800 up to 2,000 2,000 up to 2,200

9 4

What is the relative frequency of salespeople who earn $1,600 or more?

A) 29.5% B) 30.8% C) 27.5% D) 25.5% E) 29.5% F) 30.8%

89) Refer to the following information from a frequency distribution for heights of college women recorded to the nearest inch: the first two class midpoints are 69.5" and 72.5". What are the class limits for the third class?

A) 74" and up to 77" B) 74" and 76" C) 73" and 75" D) 71" and up to 74"

90) Taylor Simmons owns an online store that sells small appliance parts. She wishes to see the percentage of sales revenue earned less than a particular amount for various parts sold in her shop. What type of display should she use for each part type?

A) Frequency polygons B) Cumulative frequency polygons C) Pie charts D) Histograms

91) When data are collected using a qualitative, nominal variable (e.g., male or female), what is true about a frequency table that summarizes the data?

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A) The number of classes corresponds to the number of a variable's values.

B) Class midpoints can be computed.

C) The "2 to the k rule" can be applied.

D) The upper and lower class limits must be calculated.

92)

Refer to the following breakdown of responses to a survey of room service in a hotel.

Response Not satisfied Satisfied Highly satisfied

Frequency 20 40 60

What is the class interval for this frequency table?

A) 40 B) 20 C) None apply D) 10

93) Refer to the following frequency distribution of days absent during a calendar year by employees of a manufacturing company: Days Absent 0 up to 3 3 up to 6 6 up to 9 9 up to 12 12 up to 15

Number of Employees 13 43 36 11 14

How many employees were absent fewer than six days?

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A) 56 B) 13 C) 43 D) 58

94) A student was interested in the cigarette-smoking habits of college students and collected data from an unbiased random sample of students. The data are summarized in the following table.

Males Females Males who smoke Males who do not smoke Females who smoke Females who do not smoke

50 75 20 30 25 50

What is wrong with this frequency table?

A) The classes are not mutually exclusive.

B) Class limits cannot be computed.

C) The number of males does not equal the sum of males that smoke and do not smoke.

D) There are too many classes.

95) Refer to the following frequency distribution of days absent during a calendar year by employees of a manufacturing company: Days Absent 0 up to 3 3 up to 6 6 up to 9 9 up to 12 12 up to 15

Number of Employees 37 33 17 45 11

How many employees were absent for 6 up to 12 days?

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A) 15 B) 56 C) 62 D) 20

96) The number of employees less than the upper limit of each class at Lloyd's Fast Food Emporium is shown in the following table.

Ages 18 up to 23 23 up to 28 28 up to 33 33 up to 38 38 up to 43

Cumulative Number 6 19 52 61 65

What is it called?

A) A frequency polygon B) A cumulative frequency distribution C) A pie chart D) A histogram

97) When determining the number of classes needed for graphing continuous data, a good place to start is with A) the "5 to the k rule."

B) the "2 to the k rule."

C) converting raw data to an ordinal scale.

D) the value halfway between the highest and lowest raw data value.

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98) Refer to the following breakdown of responses to a survey of "Are you concerned about being tracked while connected to the Internet?"

Response Very concerned Somewhat concerned No concern

Frequency 140 40 20

What is the class with the greatest frequency?

A) Somewhat concerned B) Very concerned C) No concern D) None apply

99)

Refer to the following distribution:

Cost of Textbooks $25 up to $35 35 up to 45 45 up to 55 55 up to 65 65 up to 75

Frequency 2 5 7 20 16

What is the relative class frequency for the $25 up to $35 class?

A) 0.10 B) 0.05 C) 0.04 D) 0.02

100)

Refer to the following distribution of commissions.

Monthly Commissions $600 up to $800

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Class Frequencies 3

36

800 up to 1,000 1,000 up to 1,200 1,200 up to 1,400 1,400 up to 1,600 1,600 up to 1,800 1,800 up to 2,000 2,000 up to 2,200

7 11 12 40 24 9 4

What is the class interval?

A) 200 B) 400 C) 300 D) 3,500

101) To summarize the gender of students attending a college, the number of classes in a frequency table depends on the number of students. ⊚ true ⊚ false

102) When data are collected using a quantitative, ratio variable, what is true about a frequency distribution that summarizes the data?

A) A pie chart can be used to summarize the data.

B) The number of classes is equal to the number of variable values.

C) The "5 to the k rule" can be applied.

D) Upper and lower class limits must be calculated.

103) A student was studying the political party preferences of a university's student population. The survey instrument asked students to identify their political preferences—for example, Democrat, Republican, Libertarian, or another party. The best way to illustrate the frequencies for each political preference is a

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A) bar chart.

B) box plot.

C) histogram.

D) frequency polygon.

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Answer Key Test name: Chap 02_10e_Lind 1) B 2) A 3) B 4) D 5) TRUE 6) D 7) A 8) C 9) C 10) B 11) D 12) D 13) A 14) D 15) D 16) C 17) A 18) C 19) A 20) C 21) D 22) TRUE 23) TRUE 24) C 25) B 26) A Version 1

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27) B 28) B 29) C 30) C 31) A 32) C 33) TRUE 34) C 35) A 36) B 37) D 38) A 39) C 40) A 41) D 42) B 43) TRUE 44) D 45) A 46) C 47) FALSE 48) C 49) C 50) FALSE 51) C 52) D 53) D 54) B 55) D 56) D Version 1

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57) D 58) A 59) B 60) TRUE 61) B 62) TRUE 63) C 63) D 63) C 63) D 64) B 65) TRUE 66) FALSE 67) C 68) C 69) A 70) C 71) D 72) B 72) E 72) B 72) E 73) B 74) TRUE 75) D 76) A 77) C 78) B 79) TRUE 80) TRUE Version 1

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81) A 82) B 83) C 84) A 85) FALSE 86) D 87) A 88) B 88) F 88) B 88) F 89) A 90) B 91) A 92) C 93) A 94) A 95) C 96) B 97) B 98) B 99) C 100) A 101) FALSE 102) D 103) A

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CHAPTER 3 1) A sample of small bottles and their contents has the following weights (in grams): 4, 2, 5, 4, 5, 2, and 6. What is the sample variance of bottle weight?

A) 4.80 B) 6.92 C) 2.33 D) 1.96

2) The net incomes (in $millions) of a sample of steel fabricators are $86, $67, $86, and $85. What is the modal net income?

A) $85.5 B) $85 C) $67 D) $86

3) The variance is the mean of the sum of the squared deviations between each observation and the median. ⊚ true ⊚ false

4)

When computing the arithmetic mean, the smallest value in the data set A) can never be negative.

B) can never be zero.

C) can never be less than the mean.

D) can be any value.

5)

What is the relationship between the variance and the standard deviation?

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A) Variance is the square root of the standard deviation.

B) Variance is twice the standard deviation.

C) Variance is the square of the standard deviation.

D) There is no constant relationship between the variance and the standard deviation.

6) The following are the weekly amounts of welfare payments made by the federal government to a sample of six families: $139, $136, $130, $136, $147, and $136. What is the range?

A) $52 B) $0 C) $17 D) $14

7) Assume a student received the following grades for the semester: History, B; Statistics, A; Spanish, C; and English, C. History and English are 5 credit-hour courses, Statistics is a 4 credit-hour course, and Spanish is a 3 credit-hour course. If 4 grade points are assigned for an A, 3 for a B, and 2 for a C, what is the weighted mean grade for the semester?

A) 4.00 B) 1.96 C) 2.76 D) 3.01

8) In the U.S. Midwest states of Illinois, Indiana, Iowa, Kansas, Michigan, Minnesota, Missouri, Nebraska, North Dakota, Ohio, South Dakota, and Wisconsin, the number of persons who died from a pandemic virus were (in thousands) 14.4, 6.5, 2.9, 1.8, 10.6, 4.0, 4.3, 1.3, 1.0, 7.1, 1.1, 4.0, respectively. The mean, or average number of deaths was

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A) about 15.7.

B) about 13.4.

C) about 4.9.

D) about 4.

E) about 3.1.

9)

What is the sample variance of the following numbers? 6, 4, 2, 7, 1 A) 6.50 B) 2.28 C) 2.55 D) 5.20

10) A population consists of all the weights of all defensive tackles on a university’s football team. They are Johnson, 204 pounds; Patrick, 215 pounds; Junior, 207 pounds; Kendron, 212 pounds; Nicko, 214 pounds; and Cochran, 208 pounds. What is the population standard deviation (in pounds)?

A) About 16 B) About 40 C) About 100 D) About 4

11)

What is the relationship among the mean, median, and mode in a symmetric distribution?

A) They are all equal.

B) The mean is always the smallest value.

C) The mean is always the largest value.

D) The mode is the largest value.

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12) The ages of all employees at a small convenience store are 26, 36, 30, and 42. What is variance of ages for this population?

A) 6.06 B) 7.33 C) 66.58 D) 36.75

13) A sample of the paramedical fees charged by clinics revealed these amounts: $55, $49, $50, $45, $52, and $55. What is the median charge?

A) $52.00 B) $47.50 C) $55.00 D) $51.00

14) Each person who applies for an assembly job at Robert’s Electronics is given a mechanical aptitude test. One part of the test involves assembling a plug-in unit based on numbered instructions. A sample of the length of time it took 42 persons to assemble the unit was organized into the following frequency distribution.

Length of Time (in minutes) 1 up to 4 4 up to 7 7 up to 10 10 up to 13 13 up to 16 16 up to 19

Number 4 8 14 9 5 2

What is the standard deviation (in minutes)?

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A) 8.78 B) 3.89 C) 17.00 D) 6.01

15) A question in a market survey asks for a respondent’s favorite car color. Which measure of central location should be used to summarize this question?

A) Median B) Mode C) Mean D) Standard deviation

16) The ages of all the patients in the isolation ward of the hospital are 38, 26, 13, 41, and 22.

What is the population variance?

A) 106.8 B) 42.4 C) 240.3 D) 91.4

17) Production of passenger cars in Japan increased from 3.74 million in 1999 to 6.64 million in 2009. What is the geometric mean annual percent increase?

A) 4.4% B) 2.3% C) 17.8% D) 5.9% E) 50.9%

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18)

The geometric mean is the nth root of the product of n observations. ⊚ true ⊚ false

19) Which measures of central location are not affected by extremely small or extremely large values?

A) Standard deviation and mean B) Mode and median C) Mean and median D) Mean and mode

20) In the U.S. Midwest states of Illinois, Indiana, Iowa, Kansas, Michigan, Minnesota, Missouri, Nebraska, North Dakota, Ohio, South Dakota, and Wisconsin, the number of persons who died from a pandemic virus were (in thousands) 14.4, 6.5, 2.9, 1.8, 10.6, 4.0, 4.3, 1.3, 1.0, 7.1, 1.1, 4.0, respectively. The range of deaths was A) about 3.1.

B) about 4.9.

C) about 13.4.

D) about 15.7.

E) about 4.

21)

A set of ordinal-, interval-, or ratio-level data may have only one mode. ⊚ true ⊚ false

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22) In the U.S. Midwest states of Illinois, Indiana, Iowa, Kansas, Michigan, Minnesota, Missouri, Nebraska, North Dakota, Ohio, South Dakota, and Wisconsin, the number of persons who died from a pandemic virus were (in thousands) 14.4, 6.5, 2.9, 1.8, 10.6, 4.0, 4.3, 1.3, 1.0, 7.1, 1.1, 4.0, respectively. The standard deviation of deaths was A) about 4.

B) about 4.9.

C) about 13.4.

D) about 3.1.

E) about 15.7.

23)

During the past six months, a purchasing agent placed the following three orders for coal:

Tons of Coal Price per Ton

2,400 $ 27.00

4,200 $ 87.40

1,700 $ 95.00

What is the weighted arithmetic mean price per ton?

A) $89.33 B) $71.49 C) $68.62 D) $87.40

24) The Investment Research Institute reported in its Mutual Fund Fact Book that the number of mutual funds increased from 5,725 in 1999 to 7,977 in 2009. What is the geometric mean annual percent increase in the number of funds?

A) 3.37% B) 633.50% C) 39.34% D) 71.11% E) 1.03%

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25)

What is the sample variance of the following numbers? 5, 1, 8, 3, 7 A) 5.82 B) 2.59 C) 8.20 D) 2.86

26)

The sample mean A) is found by adding the data values and dividing them by (n − 1).

B) is found by adding all data values and dividing them by n.

C) is always equal to the population mean.

D) is always smaller than the population mean.

27)

For any data set, which measures of central location have only one value?

A) Mode and median B) Mode and standard deviation C) Mode and mean D) Mean and median

28)

For a data set, half of the observations are always greater than the _______.

A) mode B) standard deviation C) median D) mean

29)

What is the sample standard deviation of the following numbers? 6, 4, 2, 7, 1

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A) 5.20 B) 2.55 C) 6.50 D) 2.28

30)

The mode is the value of the observation that appears most frequently. ⊚ true ⊚ false

31) The times (in minutes) that several underwriters took to review applications for similar insurance coverage are 140, 220, 48, and 19. What is the median length of time required to review an application?

A) 67.00 B) 94.00 C) 134.00 D) 113.50

32) A stockbroker placed the following order for a customer. ● 50 shares of Kaiser Aluminum at $104 a share ● 100 shares of GTE at $25.25 a share ● 20 shares of Boston Edison at $9.125 a share What is the weighted arithmetic mean price per share?

A) $25.25 B) $46.51 C) $79.75 D) $103.50

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33) The ages of all employees at a small convenience store are 38, 26, 42, and 22. What is standard deviation of ages for this population?

A) 68.00 B) 90.67 C) 9.52 D) 8.25

34) A sample of wires coming off the production line was tested for tensile strength. The statistical results (in psi) were the following: Arithmetic mean Mode Quartile deviation Range

500 500 25 240

Median Standard deviation Mean deviation Sample size

500 40 32 100

According to the Empirical rule, the middle 95% of the wires tested had a tensile strength between approximately what two values?

A) 450 and 550 B) 420 and 580 C) 380 and 620 D) 460 and 540

35) The arithmetic mean is the sum of the quantitative observations divided by the total number of observations. ⊚ true ⊚ false

36) The number of students at a local university increased from 2,500 students to 5,000 students in 10 years. Based on a geometric mean, the university grew at an average percentage rate of

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A) 7.2 percent per year.

B) 250 students per year.

C) 1.072 percent per year.

D) 2,500 students per year.

37) For a set of data arranged or sorted in numerical order, the value of the observation in the center is called the weighted mean. ⊚ true ⊚ false

38) A value that is typical or representative of the data is referred to as a measure of central location. ⊚ true ⊚ false

39) The ages of all employees at a small convenience store are 38, 26, 42, and 22. What is variance of ages for this population?

A) 8.25 B) 9.52 C) 90.67 D) 68.00

40) The sum of the deviations of each data value from this measure of central location will always be zero.

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A) Mean B) Mode C) Median D) Standard deviation

41) The mean, as a measure of central location, would be inappropriate for which one of the following?

A) Incomes of lawyers B) Number of pages in textbooks on statistics C) Ages of adults at a senior citizen center D) Marital status of college students at a particular university

42) Sometimes, a data set has two values that have the highest and equal frequencies. In this case, the distribution of the data can best be described as _______.

A) positively skewed B) symmetric C) bimodal (having two modes) D) negatively skewed

43) For the most recent seven years, the U.S. Department of Education reported the following number of bachelor's degrees awarded in computer science: 4,033; 5,652; 6,407; 7,201; 8,719; 11,154; 15,121. What is the annual arithmetic mean number of degrees awarded?

A) About 15,962 B) About 6,217 C) About 12,240 D) About 8,327

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44)

What is the sample standard deviation of the following numbers? 3, 7, 6, 8, 5 A) 3.70 B) 1.92 C) 1.65 D) 3.94

45)

Extremely high or low scores affect the value of the median. ⊚ true ⊚ false

46) The ages of all employees at a small convenience store are 28, 38, 42, and 26. What is standard deviation of ages for this population?

A) 73.51 B) 44.75 C) 7.96 D) 6.69

47) The distribution of a sample of the outside diameters of PVC pipes approximates a symmetrical, bell-shaped distribution. The arithmetic mean is 14.0 inches, and the standard deviation is 0.1 inches. About 68% of the outside diameters lie between what two amounts?

A) 13.8 and 14.2 inches B) 13.9 and 14.1 inches C) 13.0 and 15.0 inches D) 13.5 and 14.5 inches

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48) A sample of single persons receiving Social Security payments revealed these monthly benefits: $826, $699, $1,087, $880, $839, and $965. How many observations are below the median?

A) 1 B) 3.5 C) 2 D) 3

49) The variance of a sample of 121 observations equals 441. The standard deviation of the sample equals A) 21.

B) 11.

C) 1.91.

D) 231.

50) For the past week, a company’s common stock closed with the following prices: $61.5, $62, $61.25, $60.875, and $61.5. What was the price range?

A) $1.750 B) $1.125 C) $1.875 D) $1.250

51) A sample of assistant professors on the business faculty at state-supported institutions in Ohio revealed the mean income to be $72,000 for nine months, with a standard deviation of $3,000. Using Chebyshev’s theorem, what proportion of the faculty earns more than $66,000, but less than $78,000?

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A) At least 50% B) At least 25% C) At least 75% D) At least 100%

52) The monthly amounts spent for food by families of four receiving food stamps approximates a symmetrical, normal distribution. The sample mean is $150 and the standard deviation is $20. Using the Empirical rule, about 95% of the monthly food expenditures are between what two amounts?

A) $205 and $220 B) $100 and $200 C) $85 and $105 D) $110 and $190

53) For the most recent seven years, the U.S. Department of Education reported the following number of bachelor's degrees awarded in computer science: 10,901; 9,436; 8,098; 10,960; 8,842; 10,469; 5,163. What is the annual arithmetic mean number of degrees awarded?

A) About 9,124 B) About 13,037 C) About 7,014 D) About 16,759

54)

The sample variance of hourly wages was 10. What is the sample standard deviation?

A) $1.96 B) $3.16 C) $4.67 D) $10.00

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55) Students in a statistics class answered a quiz question and the time it took each to complete it was recorded. The results are summarized in the following frequency distribution.

Length of Time (in minutes) 0 up to 2 2 up to 4 4 up to 6 6 up to 10

Number 3 6 20 8

What is the mean (in minutes)?

A) 4.0 B) 5.0 C) 4.5 D) 6.5 E) 5.5

56) A sample of the paramedical fees charged by clinics revealed these amounts: $33, $20, $37, $21, $24, and $53. What is the median charge?

A) $24.00 B) $28.50 C) $22.00 D) $33.00

57) A sample of single persons receiving Social Security payments revealed these monthly benefits: $742, $1,006, $959, $863, $921, and $1,052. How many observations are below the median?

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A) 3.5 B) 3 C) 2 D) 1

58) In the U.S. Midwest states of Illinois, Indiana, Iowa, Kansas, Michigan, Minnesota, Missouri, Nebraska, North Dakota, Ohio, South Dakota, and Wisconsin, the number of persons who died from a pandemic virus were (in thousands) 14.4, 6.5, 2.9, 1.8, 10.6, 4.0, 4.3, 1.3, 1.0, 7.1, 1.1, 4.0, respectively. The variance of deaths was A) about 4.9.

B) about 15.7.

C) about 4.

D) about 13.4.

E) about 3.1.

59) A survey item asked students to indicate their class in college: freshman, sophomore, junior, or senior. Which measure(s) of central location would be appropriate for the data generated by that questionnaire item?

A) Mean and median B) Mode only C) Mean and mode D) Mode and median

60) According to the Empirical rule, about 95% of the observations lie within plus and minus 2.00 standard deviations. ⊚ true ⊚ false

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61) Over the last six months, the following numbers of absences have been reported: 0, 12, 10, 6, 18, and 20. What is the median number of monthly absences?

A) 11 B) 15 C) 18 D) 0

62) According to Chebyshev’s theorem, at least what percent of the observations lie within plus and minus 1.75 standard deviations of the mean?

A) 67% B) 95% C) 100% D) 56%

63) Each person who applies for an assembly job at Robert's Electronics is given a mechanical aptitude test. One part of the test involves assembling a plug-in unit based on numbered instructions. A sample of the length of time it took 42 persons to assemble the unit was organized into the following frequency distribution.

Length of Time (in minutes) 1 up to 4 4 up to 7 7 up to 10 10 up to 13 13 up to 16 16 up to 19

Number 4 8 14 9 5 2

What is the mean (in minutes)?

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A) 8.53 B) 11.50 C) 9.14 D) 3.89

64) The number of students at a local university increased from 1,400 students to 5,300 students in 10 years. Based on a geometric mean, the university grew at an average percentage rate of A) 1,400 students per year.

B) 14.2 percent per year.

C) 1.142 percent per year.

D) 140 students per year.

65)

The standard deviation is the positive square root of the variance. ⊚ true ⊚ false

66) Over the last six months, the following numbers of absences have been reported: 6, 0, 10, 14, 8, and 0. What is the median number of monthly absences?

A) 6 B) 8 C) 3 D) 7

67)

During the past six months, a purchasing agent placed the following three orders for coal:

Tons of Coal

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3,000

500

19

Price per Ton

$ 28.50

$ 87.25

$ 88.00

What is the weighted arithmetic mean price per ton?

A) $68.47 B) $89.18 C) $87.25 D) $72.33

68) The sum of the differences between sample observations and the sample mean is equal to _______.

A) the mean deviation B) zero C) the range D) the standard deviation

69) In the U.S. Midwest states of Illinois, Indiana, Iowa, Kansas, Michigan, Minnesota, Missouri, Nebraska, North Dakota, Ohio, South Dakota, and Wisconsin, the number of persons who died from a pandemic virus were (in thousands) 14.4, 6.5, 2.9, 1.8, 10.6, 4.0, 4.3, 1.3, 1.0, 7.1, 1.1, 4.0, respectively. The median number of deaths was A) about 13.4.

B) about 15.7.

C) about 4.

D) about 4.9.

E) about 3.1.

70) In a company, the standard deviation of the ages of female employees is 6 years and the standard deviation of the ages of male employees is 10 years. These statistics indicate that the dispersion of age is greater for females than for males.

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⊚ ⊚

71)

true false

Which one of the following is referred to as the population mean?

A) µ B) s C) D) σ

72)

Consider two populations with the same mean. Since they have the same mean, then A) their medians must also be the same.

B) none of these are correct.

C) their modes must also be the same.

D) their standard deviations must also be the same.

73) For a data set with an odd number of observations that have been sorted from smallest to largest values, where is the median located?

A) The number of observations multiplied by 0.5 B) The number of observations divided by two C) The average of the two middle observations D) The observation in the middle

74) The Investment Research Institute reported in its Mutual Fund Fact Book that the number of mutual funds increased from 5,635 in 1999 to 8,036 in 2009. What is the geometric mean annual percent increase in the number of funds?

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A) 41.98% B) 3.61% C) 1.04% D) 681.50% E) 76.39%

75) A bottling company offers three kinds of delivery service: instant, same day, and within five days. The profit per delivery varies according to the kind of delivery. The profit for an instant delivery is less than the other kinds because the driver has to go directly to a grocery store with a small load and return to the bottling plant. To find out what effect each type of delivery has on the profit picture, the company summarized the data in the following table based on deliveries for the previous quarter: Type of Delivery Instant Same day Within five days

Frequency per Quarter Profit per Delivery 100 70 60 100 40 160

What is the weighted mean profit per delivery?

A) $142 B) $97 C) $110 D) $72

76) In a sample of 10 people, 3 persons earn $8 an hour, 6 earn $9 an hour, and 1 earns $12 an hour. The weighted mean hourly wage is $9. ⊚ true ⊚ false

77) Which measure of central location is used to determine an average annual percent increase?

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A) Geometric mean B) Mode C) Weighted mean D) Arithmetic mean

78)

What is the median of 26, 30, 24, 32, 32, 31, 27, and 29?

A) 29 B) 29.5 C) 30 D) 32

79) In the calculation of the arithmetic mean for grouped data, which value is used to represent all the values in a particular class?

A) The upper limit of the class B) The cumulative frequency preceding the class C) The lower limit of the class D) The frequency of the class E) The class midpoint

80)

What is the lowest level of measurement to which a median can be computed?

A) Nominal B) Ordinal C) Ratio D) Interval

81)

What is a disadvantage of the range as a measure of dispersion?

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A) It has no disadvantage.

B) It can be distorted by a large mean.

C) It is not in the same units as the original data.

D) It is based on only two observations.

82) In the U.S. Midwest states of Illinois, Indiana, Iowa, Kansas, Michigan, Minnesota, Missouri, Nebraska, North Dakota, Ohio, South Dakota, and Wisconsin, the number of persons who died from a pandemic virus were (in thousands) 14.4, 6.5, 2.9, 1.8, 10.6, 4.0, 4.3, 1.3, 1.0, 7.1, 1.1, 4.0,respectively. The modal number of deaths was A) about 15.7.

B) about 3.1.

C) about 4.9.

D) about 4.

E) about 13.4.

83) If the variance of the “number of daily parking tickets” issued is 100, the standard deviation is defined as the _______.

A) square root of the variance of the "number of daily parking tickets" B) absolute value of the variance of the "number of daily parking tickets" C) "number of daily parking tickets" D) "number of daily parking tickets" squared

84) On a finance exam, 15 accounting majors had an average grade of 90. On the same exam, 7 marketing majors averaged 85, and 10 finance majors averaged 93. What is the weighted mean for all 32 students taking the exam?

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A) 89.84 B) 89.33 C) 89.48 D) 10.67

85) Students in a statistics class answered a quiz question and the time it took each student to complete it was recorded. The results are summarized in the following frequency distribution.

Length of Time (in minutes) 0 up to 2 2 up to 4 4 up to 6 6 up to 10

Number 3 6 20 8

What is the standard deviation (in minutes)?

A) 3 B) 5 C) 4 D) 2

86)

For any distribution, there is an equal number of values above and below the mean. ⊚ true ⊚ false

87) The times (in minutes) that several underwriters took to review applications for similar insurance coverage are 50, 230, 52, and 57. What is the median length of time required to review an application?

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A) 141.0 B) 97.25 C) 54.5 D) 109.0

88) For any data set, Chebyshev’s theorem estimates the proportion of observations that occurs within k standard deviations of the mean, where k is greater than 1.0. ⊚ true ⊚ false

89)

A disadvantage of using an arithmetic mean to summarize a set of data is that _______.

A) it can be used for interval and ratio data B) it is always different from the median C) it can be biased by one or two extremely small or large values D) the arithmetic mean sometimes has two values

90) Assume a student received the following grades for the semester: History, B; Statistics, A; Spanish, C; and English, C. History and English are 6 credit-hour courses, Statistics is a 7 credit-hour course, and Spanish is a 4 credit-hour course. If 4 grade points are assigned for an A, 3 for a B, and 2 for a C, what is the weighted mean grade for the semester?

A) 3.12 B) 4.00 C) 2.87 D) 2.07

91) Based on the Empirical rule, what percent of the observations will lie between plus or minus two standard deviations from the mean?

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A) 2.5% B) 68% C) 95% D) 5%

92) Production of passenger cars in Japan increased from 3.94 million in 1999 to 6.74 million in 2009. What is the geometric mean annual percent increase?

A) 47.3% B) 16.6% C) 1.9% D) 4.0% E) 5.5%

93)

Variation describes the degree of dispersion in the data. ⊚ true ⊚ false

94) For a sample of similar-sized all-electric homes, the March electric bills were (to the nearest dollar): $212, $191, $176, $129, $106, $92, $108, $109, $103, $121, $175, and $194.

What is the range?

A) $120 B) $100 C) $112 D) $130

95) zero.

The sum of the deviations from the mean for the set of numbers 4, 9, and 5 will equal

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⊚ ⊚

true false

96) A purchasing agent for a trucking company is shopping for replacement tires for their trucks from two suppliers. The suppliers’ prices are the same. However, Supplier A’s tires have an average life of 60,000 miles with a standard deviation of 10,000 miles. Supplier B’s tires have an average life of 60,000 miles with a standard deviation of 2,000 miles.

Which of the following statements is true?

A) On average, Supplier A’s tires have a longer life than Supplier B’s tires.

B) The two distributions of tire life are the same.

C) The life of Supplier B’s tire is more predictable than the life of Supplier A’s tires.

D) The dispersion of Supplier A’s tire life is less than the dispersion of Supplier B’s tire life.

97) The net annual sales of a sample of small retail clothing stores were organized into the following relative frequency distribution.

Net Sales (in $ millions) 1 up to 4 4 up to 7 7 up to 10 10 up to 13 13 or more

Percent of Total 13 14 40 23 10

What is the mean net sales (in $ millions)?

A) $10.09 B) Mean cannot be computed.

C) $8.59 D) $7.09

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98) The U.S. Federal Aviation Administration reported that passenger revenues on international flights increased from $528 million in 1986 to $5,100 million in 2009. What is the geometric mean annual percent increase in international passenger revenues?

A) 9.96 B) 27.9 C) 103.6 D) 10.4

99) A bottling company offers three kinds of delivery service: instant, same day, and within five days. The profit per delivery varies according to the kind of delivery. The profit for an instant delivery is less than the other kinds because the driver has to go directly to a grocery store with a small load and return to the bottling plant. To find out what effect each type of delivery has on the profit picture, the company summarized the data in the following table based on deliveries for the previous quarter: Type of Delivery Instant Same day Within five days

Frequency per Quarter Profit per Delivery 40 110 80 160 80 80

What is the weighted mean profit per delivery?

A) $118 B) $131 C) $163 D) $93

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Answer Key Test name: Chap 03_10e_Lind 1) C 2) D 3) FALSE 4) D 5) C 6) C 7) C 8) C 9) A 10) D 11) A 12) D 13) D 14) B 15) B 16) A 17) D 18) TRUE 19) B 20) C 21) FALSE 22) A 23) B 24) A 25) C 26) B Version 1

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27) D 28) C 29) B 30) TRUE 31) B 32) B 33) D 34) B 35) TRUE 36) A 37) FALSE 38) TRUE 39) D 40) A 41) D 42) C 43) D 44) B 45) FALSE 46) D 47) B 48) D 49) A 50) B 51) C 52) D 53) A 54) B 55) B 56) B Version 1

31

57) B 58) B 59) D 60) TRUE 61) A 62) A 63) C 64) B 65) TRUE 66) D 67) D 68) B 69) C 70) FALSE 71) A 72) B 73) D 74) B 75) B 76) TRUE 77) A 78) B 79) E 80) B 81) D 82) D 83) A 84) A 85) D 86) FALSE Version 1

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87) C 88) TRUE 89) C 90) C 91) C 92) E 93) TRUE 94) A 95) TRUE 96) C 97) B 98) D 99) A

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CHAPTER 4 1) What is the value of the Pearson's coefficient of skewness for a distribution with a mean of 41, a median of 24, and a standard deviation of 6?

A) −5.17 B) +5.17 C) −8.5 D) +8.5

2)

The median of a sample will always equal the ________.

A) 50th percentile B) All of these answers are correct.

C) mode D) mean

3) If a distribution is negatively skewed, the distribution is not symmetrical and the long tail is to the left. ⊚ true ⊚ false

4)

The following graph is a ___________.

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A) stem-and-leaf display B) scatter diagram C) dot plot D) box plot

5)

The interquartile range is graphically presented in a ___________.

A) dot plot B) stem-and-leaf display C) contingency table D) box plot

6) If production determines sales, then a scatter diagram of these two variables is labeled with sales on the Y-axis and production on the X-axis. ⊚ true ⊚ false

7)

A dot plot shows the symmetry of a distribution. ⊚ true ⊚ false

8) A student scored in the 85th percentile on a standardized test. This means that the student scored lower than 85% of all students who took the test. ⊚ true ⊚ false

9)

A box plot graphically displays ______.

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A) the 25th percentile, 75th percentile, and 100th percentile value B) the minimum, maximum, 50th percentile, 20th percentile, and 80th percentile values C) the minimum, maximum, mean, 25th percentile, and 75th percentile values D) the minimum, maximum, median, 25th percentile, and 75th percentile values

10)

Pearson's coefficient of skewness is a measure of a distribution's symmetry. ⊚ true ⊚ false

11)

Quartiles divide a distribution into 10 equal parts. ⊚ true ⊚ false

12) To locate the percentile for a given observation in a data set, the data must be ___________.

A) sorted and listed from the minimum to the maximum values B) distributed symmetrically around the mean C) summarized in a frequency distribution D) displayed in a histogram

13) In the following set of data: (1, 3, 5, 6, 7, 9, 100), what are the first, second, and third quartiles?

A) 1, 5, and 100 B) 1, 6, and 100 C) 3, 6, and 9 D) 3, 5, and 9

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14)

The following graph is _______________.

A) negatively skewed B) symmetric C) positively skewed D) uniformly distributed

15)

A dot plot is best applied when _____________________.

A) the mean, median, and mode are equal B) the general shape of a distribution is symmetric C) a single variable is summarized D) the relationship between two variables is summarized

16)

A dot plot is useful for showing the range of the data. ⊚ true ⊚ false

17) In the following set of data: (2, 3, 4, 6, 7, 33, 100), what are the first, second, and third quartiles?

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A) 3, 4, and 33 B) 3, 6, and 33 C) 2, 4, and 100 D) 2, 6, and 100

18)

A dot plot is useful for quickly graphing frequencies in a small data set. ⊚ true ⊚ false

19) Which of the following is true about the correlation coefficient based on the graph below of variables X and Y?

A) The correlation coefficient will be close to +1.0.

B) The correlation coefficient must be negative.

C) The correlation coefficient will be close to zero.

D) The correlation coefficient must be positive.

20)

The coefficient of skewness is the standard deviation divided by the mean.

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⊚ ⊚

21)

true false

In a contingency table, we describe the relationship between ________.

A) two variables, one measured as an ordinal variable and the other as a ratio variable B) two variables measured at the interval or ratio level C) a variable measured on the interval or ratio level and time D) two variables measured at the ordinal or nominal level

22) A scatter diagram of sales versus production may be constructed by plotting the minimum, first quartile, median, third quartile, and maximum values of each variable. ⊚ true ⊚ false

23) A large oil company is studying the number of gallons of gasoline purchased per customer at self-service pumps. The mean number of gallons is 10.0, with a standard deviation of 3.0 gallons. The median is 10.75 gallons. What is Pearson's coefficient of skewness in this instance?

A) +0.75 B) −1.00 C) +1.00 D) −0.75

24) If a student places in the 99th percentile on an exam, she performed better than 99% of all students who completed the exam. Her performance is similar to a statement based on a __________.

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A) histogram B) frequency table C) cumulative frequency distribution D) pie chart

25) Using the following statistics to describe a distribution of data, what is the interquartile range?

Minimum = 10 Q1 = 25 Median = 50 Q3 = 75 Maximum = 95 A) 20 B) 50 C) 15 D) 85

26)

The "box" in a box plot shows the interquartile range. ⊚ true ⊚ false

27) A company wishes to know whether advertising expenditure is related to sales volume.

Using the past two years of data for these two variables, they determined the correlation coefficient is +0.93. This indicates A) a weak direct relationship between advertising expenditure and sales volume.

B) a strong direct relationship between advertising expenditure and sales volume.

C) a strong indirect relationship between advertising expenditure and sales volume.

D) a weak indirect relationship between advertising expenditure and sales volume.

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28)

The 50th percentile is referred to as the ________.

A) first quartile B) third quartile C) fourth quartile D) second quartile

29) The correlation coefficient measures the strength and direction of the relationship between two quantitative variables. ⊚ true ⊚ false

30)

The following graph illustrates _______________.

A) a distribution for a single variable B) a negative or inverse relationship C) no relationship D) a positive or direct relationship

31) A sample of experienced typists revealed that their mean typing speed is 97 words per minute and the median typing speed is 78 words per minute. The standard deviation of typing speed is 16.9 words per minute. What is the Pearson's coefficient of skewness?

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A) +3.4 B) +5.8 C) −5.8 D) −3.4

32) What is the value of the Pearson coefficient of skewness for a distribution with a mean of 17, a median of 12, and a standard deviation of 6?

A) −0.83 B) −2.5 C) +0.83 D) +2.5

33)

A box plot graphically includes the 25th, 50th, and 75th percentiles. ⊚ ⊚

true false

34)

A dot plot is useful for showing individual observations. ⊚ true ⊚ false

35)

A dot plot can be used to show _________________.

A) the interquartile range B) the general shape of a distribution for a nominal qualitative variable C) the distribution for a quantitative variable D) the mean, median, and mode

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36)

Which of the following statements is true about the correlation coefficient?

A) The correlation coefficient ranges in value from −3 to +3.

B) A correlation coefficient of zero means that two quantitative variables are not linearly related to each other.

C) A positive correlation coefficient indicates an indirect relationship between two quantitative variables.

D) A negative correlation coefficient indicates a direct relationship between two quantitative variables.

37)

What does the interquartile range describe?

A) The range of the middle 50% of the observations B) The ranges of the lower 25% and the upper 25% of the observations C) The range of the lower 50% of the observations D) The range of the upper 50% of the observations

38) The test scores for a class of 147 students are computed. What is the location of the test score associated with the third quartile?

A) 75 B) 74 C) 111 D) 37

39)

What statistics are needed to draw a box plot?

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A) The median, mean, and standard deviation B) The minimum, maximum, median, first and third quartiles C) The median and interquartile range D) The mean and standard deviation

40)

In a distribution, the second quartile corresponds with the __________.

A) mean B) variance C) mode D) median

41)

The 75th percentile is referred to as the ________.

A) second quartile B) first quartile C) fourth quartile D) third quartile

42) A sample of experienced typists revealed that their mean typing speed is 87 words per minute and the median typing speed is 73 words per minute. The standard deviation of typing speed is 16.9 words per minute. What is the Pearson coefficient of skewness?

A) −4.2 B) +2.5 C) +4.2 D) −2.5

43)

Quartiles divide a distribution into four equal parts.

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⊚ ⊚

44)

true false

The range of the software coefficient of skewness is ________.

A) values less than or equal to zero or always negative B) both positive and negative values C) values between −1 and +1 D) values greater than or equal to zero or always positive

45) A correlation coefficient is calculated and found to be equal to −1.0. Which of the following statements is true?

A) The scatter plot will show no relationship between the two variables.

B) The points in a scatter plot of the two variables will be in a straight line with a negative slope.

C) The points in the scatter plot of the two variables will slope downward from left to right but will not be in a straight line.

D) The points in a scatter plot of the two variables will be in a straight line with a positive slope.

46) A large oil company is studying the number of gallons of gasoline purchased per customer at self-service pumps. The mean number of gallons is 12, with a standard deviation of 3 gallons. The median is 13 gallons. What is Pearson's coefficient of skewness in this instance?

A) −1.20 B) +1.00 C) +1.20 D) −1.00

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47) If Pearson’s coefficient of skewness is equal to zero, the shape of the distribution is ________.

A) unknown B) negatively skewed C) positively skewed D) symmetric

48)

Percentiles divide a distribution into 100 equal parts. ⊚ true ⊚ false

49) A scatter diagram is used to illustrate a relationship between gender and the preference for Coke or Pepsi. ⊚ true ⊚ false

50) Based on the graph below, which of the following values for the correlation coefficient is most likely?

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1

2

3

2

2

5

5

2

677

8

2

889

11

3

001

(6)

3

222233

7

3

555

4

3

667

1

3

9

A) −0.875 B) +2.549 C) +0.236 D) −1.747

51)

Which of the following is not a measure of dispersion?

A) The interquartile range B) The standard deviation C) The range D) The 50th percentile

52)

The eighth decile ________.

A) is the same as the 70th percentile B) is the same as the 80th percentile C) contains at least 70% of the observations D) is the same as the 40th percentile

53)

Outliers are clearly presented in a _____________.

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A) stem-and-leaf display B) dot plot C) box plot D) contingency table

54)

A box plot shows ___________.

A) the deciles of a distribution B) the mean and variance C) the 10th and 90th percentiles of a distribution D) the relative symmetry of a distribution for a set of data

55)

The 25th percentile is referred to as the ________.

A) first quartile B) third quartile C) fourth quartile D) second quartile

56)

A box plot graphically shows the 10th and 90th percentiles. ⊚ true ⊚ false

57)

A contingency table would be used to summarize data such as ________.

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A) company employees by gender and age B) company employees by gender and organizational title C) company employees by compensation and years with the company D) company employees by compensation and age

58)

Percentiles divide a distribution into _____________.

A) 4 equal parts B) 100 equal parts C) 2 equal parts D) 10 equal parts

59)

The 67th percentile is ________.

A) the value of the observation at the 67th location B) the value above which 67% of the observations occur C) a value one less than 67% of the observations D) the value below which 67% of the observations occur

60)

A dot plot is best applied for a data set with __________.

A) more than one variable B) one mode C) 50 observations D) 1,000 observations

61)

In a scatter diagram, we describe the relationship between __________.

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A) two variables, one measured as an ordinal variable and the other as a ratio variable B) a variable measure on the interval or ratio level and time C) two variables measured at the ordinal level D) two variables measured at the interval or ratio level

62)

A dot plot is an easy way to represent the relationship between two variables. ⊚ true ⊚ false

63)

What is the possible range of values for Pearson's coefficient of skewness?

A) −3 and +3 B) −1 and +1 C) Unlimited values D) 0% and 100%

64)

The following graph is a ____________.

A) dot plot B) contingency table C) box plot D) stem-and-leaf diagram

65)

Quartiles divide a distribution into ___________.

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A) 10 equal parts B) 2 equal parts C) 4 equal parts D) 100 equal parts

66)

A relationship between two nominal variables is summarized by a contingency table. ⊚ true ⊚ false

67)

A correlation coefficient of −0.8 indicates strong indirect relationship. ⊚ true ⊚ false

68)

The diagram that is best at displaying data dispersion is a: A) scatter diagram.

B) stem-and-leaf display.

C) skewness graph.

D) box plot.

69)

A box plot shows the skewness of a distribution. ⊚ true ⊚ false

70) The test scores for a class of 171 students are computed. What is the location of the test score associated with the third quartile?

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A) 43 B) 86 C) 87 D) 129

71)

The formula

would be used to find

A) the third quartile of a data set using the Exclusive Method.

B) the median of a data set using the Inclusive Method.

C) the first quartile of a data set using the Inclusive Method.

D) the first quartile of a data set using the Exclusive Method.

72)

The Inclusive Method

A) is the only method available in Excel 2013 or 2016 to calculate quartiles.

B) determines different locations for the first and third quartiles than the Exclusive Method.

C) uses the same formula to calculate first and third quartiles as the Exclusive Method.

D) determines the same location of the first and third quartiles as the Exclusive Method.

73)

A dot plot shows ____________.

A) the relationship between two variables B) the mean, median, and mode C) the general shape of a distribution D) the interquartile range

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74)

The following graph is a __________.

A) contingency table B) stem-and-leaf display C) dot plot D) box plot

75)

A correlation coefficient of +0.08 indicates strong positive correlation. ⊚ true ⊚ false

76)

The 50th percentile of a distribution is the same as the distribution mean. ⊚ true ⊚ false

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Answer Key Test name: Chap 04_10e_Lind 1) D 2) A 3) TRUE 4) B 5) D 6) TRUE 7) TRUE 8) FALSE 9) D 10) TRUE 11) FALSE 12) A 13) C 14) C 15) C 16) TRUE 17) B 18) TRUE 19) C 20) FALSE 21) D 22) FALSE 23) D 24) C 25) B 26) TRUE Version 1

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27) B 28) D 29) TRUE 30) D 31) A 32) D 33) TRUE 34) TRUE 35) C 36) B 37) A 38) C 39) B 40) D 41) D 42) B 43) TRUE 44) B 45) B 46) A 47) D 48) TRUE 49) FALSE 50) A 51) D 52) B 53) C 54) D 55) A 56) FALSE Version 1

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57) B 58) B 59) D 60) C 61) D 62) FALSE 63) A 64) A 65) C 66) TRUE 67) TRUE 68) D 69) TRUE 70) D 71) D 72) B 73) C 74) D 75) FALSE 76) FALSE

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CHAPTER 5 1) The National Center for Health Statistics reported that of every 883 deaths in recent years, 24 resulted from an automobile accident, 182 from cancer, and 333 from heart disease.

What is the probability that a particular death is due to an automobile accident?

A) 182/883, or 0.206 B) 24/333, or 0.072 C) 24/883, or 0.027 D) 539/883, or 0.610

2) A survey of top executives revealed that 35% of them regularly read Time magazine, 20% read Newsweek, and 40% read U.S. News & World Report. A total of 10% read both Time and U.S. News & World Report. What is the probability that a particular top executive reads either Time or U.S. News & World Report regularly?

A) 0.65 B) 0.85 C) 1.00 D) 0.06

3) A study of interior designers' opinions with respect to the most desirable primary color for executive offices showed the following: Primary Color Red Orange Yellow Green Blue Indigo Violet

Number of Opinions 92 86 46 91 37 46 2

What is the probability that a designer does not prefer blue?

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A) 0.9075 B) 0.8850 C) 0.7725 D) 1.0000

4) The probability of a particular event occurring, given that another event has occurred, is known as a(n) _______.

A) joint probability B) empirical probability C) tree diagram D) conditional probability

5)

When an experiment is conducted "without replacement," _______.

A) the experiment can be illustrated with a Venn diagram B) events are dependent C) the probability of two or more events is computed as a joint probability D) events are equally likely

6) An automatic machine inserts mixed vegetables into a plastic bag. Past experience revealed that some packages were underweight and some were overweight, but most of them had satisfactory weight.

Weight Underweight Satisfactory Overweight

% of Total 2.5 90.0 7.5

What is the probability of selecting three packages that are overweight?

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A) 0.0004219 B) 0.075 C) 0.0000156 D) 0.0000001

7) The probability of rolling a 3 or 2 on a single die is an example of mutually exclusive events. ⊚ true ⊚ false

8)

A study of 400 computer service firms revealed these incomes after taxes:

Income After Taxes Under $1 million $1 million up to $20 million $20 million or more

Number of Firms 128 124 148

What is the probability that a particular firm selected has $1 million or more in income after taxes?

A) 0.32 B) 0.06 C) 0.00 D) 0.68

9) When applying the special rule of addition for mutually exclusive events, the joint probability is _______.

A) 1 B) 0 C) unknown D) 0.5

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10) A method of assigning probabilities based upon judgment, opinions, and available information is referred to as the _____.

A) probability method B) classical method C) subjective method D) empirical method

11) A group of employees of Unique Services will be surveyed about a new pension plan. Indepth interviews with each employee selected in the sample will be conducted. The employees are classified as follows.

Classification Supervisors Maintenance Production Management Secretarial

Event A B C D E

Number of Employees 120 50 1,460 302 68

What is the probability that the first person selected is classified as a maintenance employee?

A) 0.025 B) 1.00 C) 0.50 D) 0.20

12) In a management trainee program, 80% of the trainees are female, while 20% are male.

Ninety percent of the females attended college; 78% of the males attended college. A management trainee is selected at random. What is the correct probability notation for the joint probability of selecting a female who did not attend college?

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A) P(female) P(did attend college | female) B) P(female) P(did not attend college | female) C) P(did attend college) D) P(did attend college) P(female | did not attend college)

13) A university recently surveyed 500 students to determine which new fitness area to offer in its recreation facility. The results of the survey are summarized in the following table:

Class Level Year 1-2 Year 3-4 Graduate Student

Preferred Fitness Area Spinning Room Climbing Wall Ellipticals 43 82 28 80 44 63 88 52 20

What is the probability that a randomly selected student is interested in a spinning room and that they are a graduate student?

A) 0.550 B) 0.176 C) 0.418 D) 0.733

14) A university recently surveyed 500 students to determine which new fitness area to offer in its recreation facility. The results of the survey are summarized in the following table:

Class Level Year 1-2 Year 3-4 Graduate Student

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Preferred Fitness Area Spinning Room Climbing Wall Ellipticals 41 81 25 75 78 44 87 49 20

5

What is the probability that a randomly selected student is interested in a spinning room given that they are a graduate student?

A) 0.558 B) 0.258 C) 0.426 D) 0.174

15) The first card selected from a standard 52-card deck was a king. If it is not returned to the deck, what is the probability that a king will be drawn on the second selection?

A) 3/51 or 0.0588 B) 1/51 or 0.0196 C) 1/3 or 0.33 D) 1/13 or 0.077

16) A board of directors consists of eight men and four women. A four-member search committee is randomly chosen to recommend a new company president. What is the probability that all four members of the search committee will be women?

A) 1/120, or 0.00083 B) 1/8, or 0.125 C) 1/495, or 0.002 D) 1/16, or 0.0625

17) An electronics firm sells four models of stereo receivers, three amplifiers, and six speaker brands. When the four types of components are sold together, they form a "system." How many different systems can the electronics firm offer?

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A) 72 B) 36 C) 18 D) 144

18) The first card selected from a standard 52-card deck was a king. If it is returned to the deck, what is the probability that a king will be drawn on the second selection?

A) 1/13 or 0.077 B) 1/3 or 0.33 C) 12/13 or 0.923 D) 1/4 or 0.25

19) Your favorite soccer team has two remaining matches to complete the season. The possible outcomes of a soccer match are win, lose, or tie. What is the possible number of outcomes for the season?

A) 6 B) 2 C) 4 D) 9

20)

To apply the special rule of addition, the events must be mutually exclusive. ⊚ true ⊚ false

21) An individual can assign a subjective probability to an event based on the individual's knowledge about the event.

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⊚ ⊚

true false

22) Each salesperson in a large department store chain is rated on his or her sales ability and potential for advancement. The data for the 500 sampled salespeople are summarized in the following table.

Sales ability

Below average Average Above average

Potential for Advancement Fair Good Excellent 16 12 22 45 60 45 93 72 135

What is the probability that a salesperson selected at random will have below-average sales ability and fair potential for advancement?

A) 0.10 B) 0.16 C) 0.032 D) 0.32

23) A developer of a new subdivision wants to build homes that are all different. There are three different interior plans that can be combined with any of five different home exteriors. How many different homes can be built?

A) 15 B) 10 C) 30 D) 8

24)

If two events are mutually exclusive, then P(A and B) = P(A) × P(B).

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⊚ ⊚

25)

true false

<p>What does

equal?

A) 36 B) 640 C) 120 D) 10

26) There are 25 AAA batteries in a box and 10 are defective. Two batteries are selected without replacement. What is the probability of selecting a defective battery followed by another defective battery?

A) 1/11, or 0.09 B) 1/2, or 0.50 C) 1/1000, or about 0.0010 D) 3/20, or about 0.15

27) The joint probability of two independent events, A and B, is computed as P(A and B) = P(A) × P(B). ⊚ true ⊚ false

28) Each salesperson in a large department store chain is rated on their sales ability and their potential for advancement. The data for the 500 sampled salespeople are summarized in the following table.

Sales ability

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Below average

Potential for Advancement Fair Good Excellent 16 12 22

9

Average Above average

45 93

60 72

45 135

What is the probability that a salesperson selected at random has above-average sales ability and has excellent potential for advancement?

A) 0.50 B) 0.20 C) 0.75 D) 0.27

29) Six basic colors are used in decorating a new condominium. They are applied to a unit in groups of four colors. One unit might have gold as the principal color, blue as a complementary color, red as the accent color, and touches of white. Another unit might have blue as the principal color, white as the complementary color, gold as the accent color, and touches of red. If repetitions are permitted, how many different units can be decorated?

A) 7,825 B) 125 C) 25 D) 1,296

30)

An experiment may have ____________.

A) only one outcome B) several events C) only two outcomes D) one or more outcomes

31) A group of employees of Unique Services will be surveyed about a new pension plan. Indepth interviews with each employee selected in the sample will be conducted. The employees are classified as follows.

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Classification Supervisors Maintenance Production Management Secretarial

Event A B C D E

Number of Employees 120 50 1,460 302 68

What is the probability that the first person selected is either in maintenance or in secretarial?

A) 0.059 B) 0.001 C) 0.015 D) 0.200

32) Each salesperson in a large department store chain is rated on his or her sales ability and potential for advancement. The data for the 500 sampled salespeople are summarized in the following table.

Sales ability

Below average Average Above average

Potential for Advancement Fair Good Excellent 18 14 24 46 62 48 91 70 127

What is the probability that a salesperson selected at random will have an excellent potential for advancement given he or she also has average sales ability?

A) 0.44 B) 0.25 C) 0.31 D) 0.42

33) An illustration of an experiment is turning the ignition key of an automobile as it comes off the assembly line to determine whether or not the engine will start.

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⊚ ⊚

true false

34) A rug manufacturer has decided to use seven compatible colors in her rugs. However, in weaving a rug, only five spindles can be used. In advertising, the rug manufacturer wants to indicate the number of different color groupings for sale. How many color groupings using the seven colors taken five at a time are there? (This assumes that five different colors will go into each rug—in other words, there are no repetitions of color.)

A) 42 B) 840 C) 7 D) 21

35) When an event's probability depends on the occurrence of another event, the probability is a(n) ___________.

A) conditional probability B) joint probability C) mutually exclusive probability D) empirical probability

36) A coin is tossed four times. The joint probability that all four tosses will result in a head is ¼ or 0.25. ⊚ true ⊚ false

37) In a management trainee program, 80% of the trainees are female, while 20% are male.

Ninety percent of the females attended college; 78% of the males attended college. A management trainee is selected at random. What is the correct probability notation for the joint probability of selecting a male who did not attend college?

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A) P(male) P(did not attend college | male) B) P(did not attend college) C) P(male) P(did not attend college) D) P(did not attend college) P(male | did not attend college)

38) The National Center for Health Statistics reported that of every 1,333 deaths in recent years, 60 resulted from an automobile accident, 254 from cancer, and 423 from heart disease.

What is the probability that a particular death is due to an automobile accident?

A) 60/423, or 0.142 B) 254/1,333, or 0.191 C) 737/1,333, or 0.553 D) 60/1,333, or 0.045

39)

The result of a particular experiment is called a(n) ___________.

A) event B) outcome C) conditional probability D) observation

40) A study of interior designers' opinions with respect to the most desirable primary color for executive offices showed the following: Primary Color Red Orange Yellow Green Blue Indigo Violet

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Number of Opinions 92 86 46 91 37 46 2 13

What is the probability that a designer does not prefer yellow?

A) 1.000 B) 0.765 C) 0 D) 0.885

41) A firm offers routine physical examinations as part of a health service program for its employees. The exams showed that 16% of the employees needed corrective shoes, 23% needed major dental work, and 3% needed both corrective shoes and major dental work. What is the probability that an employee selected at random will need either corrective shoes or major dental work?

A) 0.67 B) 1.00 C) 0.36 D) 0.41

42) A group of employees of Unique Services will be surveyed about a new pension plan. Indepth interviews with each employee selected in the sample will be conducted. The employees are classified as follows: Classification Supervisors Maintenance Production Management Secretarial

Event A B C D E

Number of Employees 120 50 1,460 302 68

What is the probability that the first person selected is either in management or in supervision?

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A) 0.21 B) 0 C) 0.15 D) 0.06

43) The joint probability of two Events, A and B, that are not independent is computed as P(A and B) = P(A)× P(B|A). ⊚ true ⊚ false

44)

When are two experimental outcomes mutually exclusive?

A) When they overlap on a Venn diagram.

B) When the joint probability of the two outcomes is not equal to zero.

C) If one outcome occurs, then the other cannot.

D) When the probability of one affects the probability of the other.

45) A supplier delivers an order for 20 electric toothbrushes to a store. By accident, three of the electric toothbrushes are defective. What is the probability that the first two electric toothbrushes sold are defective?

A) 3/20 or 0.15 B) 3/190 or 0.01579 C) 3/17 or 0.176 D) 1/4 or 0.25

46) Consider a tennis tournament involving twenty (20) players who must play each other.

How many total matches are played with these twenty (20) players?

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A) 40 B) 100 C) 190 D) 20

47) A study of interior designers' opinions with respect to the most desirable primary color for executive offices showed the following: Primary Color Red Orange Yellow Green Blue Indigo Violet

Number of Opinions 86 80 52 85 43 52 2

What is the probability that a designer does not prefer yellow?

A) 1.000 B) 0 C) 0.870 D) 0.780

48) An Airbnb home has installed a combination lock with pushbuttons labeled A though F (six buttons) and any of these buttons can be used in any order. For example, ABAA, FDBA, and CCDD are valid codes. How many different codes does this lock provide?

A) 180 B) 360 C) 1,296 D) 24

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49)

Which approach to probability is exemplified by the following formula?

Probability of an event = Number of times event occurred in the past/Total number of observations A) The classical approach B) None of these answers are correct.

C) The subjective approach D) The empirical approach

50) If A and B are mutually exclusive events with P(A) = 0.2 and P(B) = 0.6, then P(A or B) = _____.

A) 0.12 B) 0.00 C) 0.40 D) 0.80

51) The numbers 0 through 9 are used in code groups of four to identify an item of clothing.

Code 1083 might identify a blue blouse, size medium. The code group 2031 might identify a pair of pants, size 18, and so on. Repetitions of numbers are not permitted—in other words, the same number cannot be used more than once in a total sequence. As examples, 2,256; 2,562; or 5,559 would not be permitted. How many different code groups can be designed?

A) 120 B) 5,040 C) 620 D) 10,200

52)

Which approach to probability assumes that events are equally likely?

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A) Classical B) Subjective C) Empirical D) Mutually exclusive

53) If there are "m" ways of doing one thing, and "n" ways of doing another thing, the multiplication formula states that there are (m) × (n) ways of doing both. ⊚ true ⊚ false

54) You are assigned to design color codes for different parts. Three colors are used to code on each part. Once a combination of three colors is used—such as green, yellow, and red—these three colors cannot be rearranged to use as a code for another part. If there are 35 combinations, how many colors are available?

A) 7 B) 5 C) 9 D) 11

55) In a management trainee program, 80% of the trainees are female, while 20% are male.

Ninety percent of the females attended college; 78% of the males attended college. A management trainee is selected at random. What is the probability that the person selected is a female who did not attend college?

A) 0.20 B) 0.08 C) 0.80 D) 0.25

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56) A university recently surveyed 500 students to determine which new fitness area to offer in its recreation facility. The results of the survey are summarized in the following table:

Class Level Year 1-2 Year 3-4 Graduate Student

Preferred Fitness Area Spinning Room Climbing Wall Ellipticals 38 81 21 73 88 53 82 45 19

What is the probability that a randomly selected student is interested in a spinning room given that they are a graduate student?

A) 0.178 B) 0.749 C) 0.562 D) 0.430

57) A joint probability measures the likelihood that two or more events will happen concurrently. ⊚ true ⊚ false

58) If two events A and B are mutually exclusive, what does the special rule of addition state?

A) P(A or B) = P(A)− P(B) B) P(A and/or B) = P(A) + P(B) C) P(A and B) = P(A) + P(B) D) P(A or B) = P(A) + P(B)

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59) A tire manufacturer advertises, "The median life of our new all-season radial tire is 50,000 miles. An immediate adjustment will be made on any tire that does not last 50,000 miles." You purchased four of these tires. What is the probability that all four tires will wear out before traveling 50,000 miles?

A) 1/64 or 0.0156 B) 1/16 or 0.0625 C) 1/4 or 0.25 D) 1/10 or 0.10

60) The complement rule states that the probability of an event not occurring is equal to 1 minus the probability of its occurrence. ⊚ true ⊚ false

61) In a management trainee program, 80% of the trainees are female, while 20% are male.

Ninety percent of the females attended college; 78% of the males attended college. A management trainee is selected at random. What is the probability that the person selected is a female who attended college?

A) 0.72 B) 0.25 C) 0.08 D) 0.20

62)

If two events are independent, then their joint probability is computed with _______.

A) the special rule of addition B) the Bayes’ theorem C) the general rule of multiplication D) the special rule of multiplication

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63) The ATP men’s professional tennis tour ends with a tournament involving a first-round “round-robin” matchup of four tennis players who must play each other to determine who advances. How many total first-round matches are played with these four players?

A) 10 B) 6 C) 4 D) 8

64) An Airbnb home has installed a combination lock with pushbuttons labeled A though F (six buttons) and uses four of these buttons in any order. Pushbuttons cannot be used more than once to unlock the door. For example, a code such as AFDC is allowed, but AFDA is not. How many different codes does this lock provide?

A) 24 B) 1,296 C) 180 D) 360

65) A university recently surveyed 500 students to determine which new fitness area to offer in its recreation facility. The results of the survey are summarized in the following table:

Class Level Year 1-2 Year 3-4 Graduate Student

Preferred Fitness Area Spinning Room Climbing Wall Ellipticals 41 81 25 75 78 44 87 49 20

What is the probability that a randomly selected student is interested in a spinning room and that they are a graduate student?

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A) 0.174 B) 0.558 C) 0.558 D) 0.426

66) Each salesperson in a large department store chain is rated on his or her sales ability and potential for advancement. The data for the 500 sampled salespeople are summarized in the following table.

Sales ability

Below average Average Above average

Potential for Advancement Fair Good Excellent 16 12 22 45 60 45 93 72 135

What is the probability that a salesperson selected at random will have average sales ability and good potential for advancement?

A) 0.525 B) 0.09 C) 0.30 D) 0.12

67)

How many permutations of the three letters C, D, and E are possible?

A) 8 B) 0 C) 3 D) 6

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68) The number of permutations for any scenario will always be greater than or equal to the number of combinations. ⊚ ⊚

69)

true false

What does the complement rule state?

A) P(A) = P(A) × P(B) B) P(A) = 1 − P(not A) C) P(A) = P(A) − P(B) D) P(A) = P(A)X + P(B)

70) A university recently surveyed 500 students to determine which new fitness area to offer in its recreation facility. The results of the survey are summarized in the following table.

Class Level Year 1-2 Year 3-4 Graduate Student

Preferred Fitness Area Spinning Room Climbing Wall Ellipticals 41 81 25 75 78 44 87 49 20

What is the probability that a randomly selected student prefers a climbing wall or is in Year 3– 4?

A) 0.156 B) 0.810 C) 0.375 D) 0.654

71)

The probability of two or more events occurring concurrently is called a(n) _______.

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A) empirical probability B) conditional probability C) tree diagram D) joint probability

72) A survey of top executives revealed that 29% of them regularly read Time magazine, 22% read Newsweek, and 39% read U.S. News & World Report. A total of 11% read both Time and U.S. News & World Report. What is the probability that a particular top executive reads either Time or U.S. News & World Report regularly?

A) 1.00 B) 0.07 C) 0.79 D) 0.57

73)

If P(A) = 0.62, P(B) = 0.47, and P(A or B) = 0.88, then P(A and B) = _____.

A) 0.6700 B) 1.9700 C) 0.2914 D) 0.2100

74) The probability of rolling a 3 or 2 on a single die is an example of an empirical probability. ⊚ true ⊚ false

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75) The ABCD football association is considering a Super Ten Football Conference. The top 10 football teams in the country, based on past records, would be members of the Super Ten Conference. Each team would play every other team in the conference during the season and the team winning the most games would be declared the national champion. How many games would the conference commissioner have to schedule each year? (Remember, Oklahoma versus Michigan is the same as Michigan versus Oklahoma.)

A) 125 B) 50 C) 14 D) 45

76) A group of employees of Unique Services will be surveyed about a new pension plan. Indepth interviews with each employee selected in the sample will be conducted. The employees are classified as follows: Classification Supervisors Maintenance Production Management Secretarial

Event A B C D E

Number of Employees 150 65 1,390 344 81

What is the probability that the first person selected is either in management or in supervision?

A) 0 B) 0.07 C) 0.24 D) 0.17

77) A lamp manufacturer designed five lamp bases and four lampshades that could be used together. How many different arrangements of base and shade can be offered?

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A) 15 B) 10 C) 5 D) 20

78) Each salesperson in a large department store chain is rated on his or her sales ability and potential for advancement. The data for the 500 sampled salespeople are summarized in the following table.

Sales ability

Below average Average Above average

Potential for Advancement Fair Good Excellent 16 12 22 45 60 45 93 72 135

What is the probability that a salesperson selected at random will have an excellent potential for advancement given they also have above-average sales ability?

A) 0.27 B) 0.45 C) 0.404 D) 0.60

79)

A study of 200 computer service firms revealed these incomes after taxes:

Income After Taxes Under $1 million $1 million up to $20 million $20 million or more

Number of Firms 102 61 37

What is the probability that a particular firm selected has $1 million or more in income after taxes?

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A) 0.49 B) 0.00 C) 0.51 D) 0.25

80) A sales representative calls on four hospitals in Westchester County. It is immaterial what order he calls on them. How many ways can he organize his calls?

A) 120 B) 37 C) 24 D) 4

81) In a management trainee program, 80% of the trainees are female, while 20% are male.

Ninety percent of the females attended college; 78% of the males attended college. A management trainee is selected at random. What is the probability that the person selected is a male who did not attend college?

A) 0.440 B) 0.256 C) 0.044 D) 0.801

82) A firm offers routine physical examinations as part of a health service program for its employees. The exams showed that 8% of the employees needed corrective shoes, 15% needed major dental work, and 3% needed both corrective shoes and major dental work. What is the probability that an employee selected at random will need either corrective shoes or major dental work?

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A) 1.00 B) 0.25 C) 0.20 D) 0.50

83)

Probabilities are important information when __________.

A) using inferential statistics B) applying descriptive statistics C) summarizing a data set with a frequency chart D) computing cumulative frequencies

84) Giorgio offers the person who purchases an 8-ounce bottle of Allure two free gifts, chosen from the following: an umbrella, a 1-ounce bottle of Midnight, a feminine shaving kit, a raincoat, or a pair of rain boots. If you purchased Allure, what is the probability you randomly select an umbrella and a shaving kit in that order?

A) 0.20 B) 1.00 C) 0.05 D) 0.00

85) A study by the National Park Service revealed that 50% of the vacationers going to the Rocky Mountain region visit Yellowstone Park, 40% visit the Grand Tetons, and 35% visit both.

What is the probability that a vacationer will visit at least one of these magnificent attractions?

A) 0.95 B) 0.05 C) 0.55 D) 0.35

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86) Each salesperson in a large department store chain is rated on his or her sales ability and potential for advancement. The data for the 500 sampled salespeople are summarized in the following table.

Sales ability

Below average Average Above average

Potential for Advancement Fair Good Excellent 16 12 22 45 60 45 93 72 135

What is the probability that a salesperson selected at random will have an excellent potential for advancement given he or she also has average sales ability?

A) 0.30 B) 0.45 C) 0.27 D) 0.40

87) A study of interior designers' opinions with respect to the most desirable primary color for executive offices showed the following: Primary Color Red Orange Yellow Green Blue Indigo Violet

Number of Opinions 52 46 86 51 77 86 2

What is the probability that a designer does not prefer blue?

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A) 1.0000 B) 0.8075 C) 0.7850 D) 0.8725

88) In a finance class, the final grade is based on three tests. Historically, the instructor tells the class that the joint probability of scoring As on the first two tests is 0.5. A student assigns a probability of 0.9 that she will get an A on the first test. What is the probability that the student will score an A on the second test given that she scored an A on the first test?

A) 0.56 B) 0.50 C) 0.90 D) 0.95

89)

A combination of a set of objects is defined by the order of the objects. ⊚ true ⊚ false

90) A study of interior designers' opinions with respect to the most desirable primary color for executive offices showed the following: Primary Color Red Orange Yellow Green Blue Indigo Violet

Number of Opinions 92 86 46 91 37 46 2

What is the probability that a designer does not prefer red?

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A) 0.73 B) 0.77 C) 1.00 D) 0.23

91) A gumball machine has just been filled with 50 black, 150 white, 100 red, and 100 yellow gumballs that have been thoroughly mixed. Sue and Jim each purchase one gumball.

What is the likelihood that both Sue and Jim will get red gumballs?

A) 0.062 B) 0.33 C) 0.50 D) 0.75

92) A board of directors consists of ten men and four women. A four-member search committee is randomly chosen to recommend a new company president. What is the probability that all four members of the search committee will be women?

A) 1/18, or 0.0556 B) 1/10, or 0.100 C) 1/140, or 0.0071 D) 1/1001, or 0.001

93) An automatic machine inserts mixed vegetables into a plastic bag. Past experience revealed that some packages were underweight and some were overweight, but most of them had satisfactory weight.

Weight Underweight Satisfactory Overweight

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% of Total 2.5 90.0 7.5

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What is the probability of selecting three packages that are satisfactory?

A) 0.810 B) 0.729 C) 0.900 D) 0.075

94) There are 10 AAA batteries in a box and 3 are defective. Two batteries are selected without replacement. What is the probability of selecting a defective battery followed by another defective battery?

A) 1/2, or 0.50 B) 1/4, or 0.25 C) 1/15, or about 0.07 D) 1/120, or about 0.0083

95)

A graphical method used to calculate joint and conditional probabilities is _______.

A) a histogram B) inferential statistics C) a tree diagram D) a Venn diagram

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Answer Key Test name: Chap 05_10e_Lind 1) C 2) A 3) A 4) D 5) B 6) A 7) TRUE 8) D 9) B 10) C 11) A 12) A 13) B 14) A 15) A 16) C 17) A 18) A 19) D 20) TRUE 21) TRUE 22) C 23) A 24) FALSE 25) D 26) D Version 1

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27) TRUE 28) D 29) D 30) D 31) A 32) C 33) TRUE 34) D 35) A 36) FALSE 37) A 38) D 39) B 40) D 41) C 42) A 43) TRUE 44) C 45) B 46) C 47) C 48) C 49) D 50) D 51) B 52) A 53) TRUE 54) A 55) B 56) C Version 1

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57) TRUE 58) D 59) B 60) TRUE 61) A 62) D 63) B 64) D 65) A 66) D 67) D 68) TRUE 69) B 70) D 71) D 72) D 73) D 74) FALSE 75) D 76) C 77) D 78) B 79) A 80) C 81) C 82) C 83) A 84) C 85) C 86) A Version 1

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87) B 88) A 89) FALSE 90) B 91) A 92) D 93) B 94) C 95) C

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CHAPTER 6 1) Sponsors of a local charity decided to attract wealthy patrons to its $500-a-plate dinner by allowing each patron to buy a set of 16 tickets for the gaming tables. The chance of winning a prize for each of the 16 plays is 45–55. If you bought 16 tickets, what is the chance of winning 11 or more prizes?

A) 0.008 B) 0.229 C) 0.688 D) 0.049

2) A company is studying the number of monthly absences among its 125 employees. The following probability distribution shows the likelihood that people were absent 0, 1, 2, 3, 4, or 5 days last month.

Number of Days Absent 0 1 2 3 4 5

Probability 0.60 0.20 0.12 0.04 0.04 0.00

What is the mean number of days absent?

A) 2.5 B) 0.72 C) 0.40 D) 1.00

3) An insurance agent has appointments with 8 prospective clients tomorrow. From past experience the agent knows that the probability of making a sale on any appointment is 0.30.

Using the rules of probability, what is the likelihood that the agent will sell a policy to exactly seven of the eight prospective clients?

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A) 0.160 B) 0.250 C) 0.125 D) 0.001

4)

The following is a binomial probability distribution with n = 3 and π = 0.28: x 0 1 2 3

P(x) 0.373 0.435 0.169 0.022

The variance of the distribution is _________.

A) 1.500 B) 0.930 C) 0.605 D) 0.720

5) A true/false test consists of six questions. If you guess the answer to each question, what is the probability of getting all six questions correct?

A) 0.250 B) 0.062 C) 0.016 D) 0

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6) David's gasoline station offers 11 cents off per gallon if the customer pays in cash and does not use a credit card. Past evidence indicates that 47% of all customers pay in cash. During a one-hour period, 15 customers buy gasoline at this station. What is the probability that at least 10 pay in cash?

A) 0.103 B) 0.035 C) 0.066 D) 0.890

7)

The following is a binomial probability distribution with n = 3 and π = 0.20: x 0 1 2 3

P(x) 0.512 0.384 0.096 0.008

The variance of the distribution is _________.

A) 0.895 B) 0.690 C) 0.480 D) 1.500

8) Data show that the weight of an offensive linesman may be any weight between 200 and 350 pounds. The distribution of weight is based on a ______________.

A) qualitative variable B) All of these answers are correct.

C) continuous random variable D) discrete random variable

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9)

The mean of a probability distribution is called its expected value. ⊚ true ⊚ false

10)

For a binomial distribution, the mean is 6.4 and n = 8. What is π for this distribution?

A) 1.3 B) 6.4 C) 0.1 D) 0.8

11)

Which one of the following is not a condition of the binomial distribution?

A) Sampling at least 10 trials B) Only two outcomes C) Independent trials D) The probability of success remains constant from trial to trial.

12) A machine shop has 100 drill presses and other machines in constant use. The probability that a machine will become inoperative during a given day is 0.004. During some days, no machines are inoperative, but on other days, one, two, three, or more are broken down. What is the probability that fewer than two machines will be inoperative during a particular day?

A) 0.9384 B) 0.6703 C) 0.2681 D) 0.0400

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13) In a large metropolitan area, past records revealed that 30% of all the high school graduates go to college. From 20 graduates selected at random, what is the probability that exactly 8 will go to college?

A) 0.887 B) 0.400 C) 0.231 D) 0.114

14)

Which shape describes a Poisson distribution?

A) All of these answers are correct.

B) Negatively skewed C) Symmetrical D) Positively skewed

15) In a family of three children, what is the probability that exactly one child is a girl, assuming that the probability of a girl birth is ½?

A) 0.500 B) 0.333 C) 0.375 D) 0.875

16)

The mean or expected value for a binomial probability distribution is _________.

A) μ = πn(1 − n) B) μ = nπ C) μ = nπ(1 − π) D) μ = π(1 − π)

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17) A company is studying the number of monthly absences among its 125 employees. The following probability distribution shows the likelihood that people were absent 0, 1, 2, 3, 4, or 5 days last month.

Number of Days Absent 0 1 2 3 4 5

Probability 0.60 0.20 0.12 0.04 0.04 0.00

What is the variance of the number of days absent?

A) 1.1616 B) 1.41 C) 5.00 D) 55.52

18)

In a Poisson distribution, the variance is equal to ___________.

A) e −x B) nπ C) D) E)

19) A statistics professor receives an average of five e-mail messages per day from students.

Assume the number of messages approximates a Poisson distribution. What is the probability that on a randomly selected day she will have two messages?

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A) 0.0067 B) 0.0842 C) 0.4200 D) 0.0014

20) In a family of three children, what is the probability that at least one child is a girl, assuming that the probability of a girl birth is ½.

A) 0.500 B) 0.875 C) 0.333 D) 0.375

21)

In a Poisson distribution, the probability of success may vary from trial to trial. ⊚ true ⊚ false

22) Chances are 50–50 that a newborn baby will be a girl. For families with five children, what is the probability that all the children are girls?

A) 0.001 B) 0.900 C) 0.031 D) 0.250

23)

Which of the following is NOT a characteristic of a binomial probability distribution?

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A) Each trial is independent.

B) Each outcome is mutually exclusive.

C) The probability of success remains constant from trial to trial.

D) The number of trials is limited to two.

24)

What is the only variable in the Poisson probability formula?

A) e B) x C) π D) P

25)

Which of the following is correct about a probability distribution?

A) The probability of each outcome must be between 0.0 and 1.0 inclusive.

B) The outcomes must be mutually exclusive.

C) The sum of all possible outcomes must equal 1.0.

D) All of these answers are correct.

26) A company is studying the number of monthly absences among its 125 employees. The following probability distribution shows the likelihood that people were absent 0, 1, 2, 3, 4, or 5 days last month.

Number of Days Absent 0 1 2 3 4 5

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Probability 0.60 0.20 0.12 0.04 0.04 0.00

8

What is the mode of the distribution?

A) 0.72 days B) 0 days C) 2.5 days D) 3 days

27) Sweetwater & Associates write weekend trip insurance at a very nominal charge. Records show that the probability that a motorist will have an accident during the weekend and file a claim is 0.0005. Suppose they wrote 400 policies for the coming weekend, what is the probability that exactly two claims will be filed?

A) 0.0164 B) 0.8187 C) 0.0001 D) 0.2500

28)

For the following distribution. x 0 1 2 3

P(x) 0.900 0.09 0.007 0.003

What is the mean of the distribution?

A) 1.140 B) 0.113 C) 0.564 D) 2.100

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29)

A random variable represents the outcome of an experiment. ⊚ true ⊚ false

30) If the mean of Poisson probability distribution is with µ = 0.50, what is the variance of the distribution?

A) 0.5000 B) 1.0000 C) 0.8966 D) 3.0000

31)

For the following distribution. x 0 1 2 3

P(x) 0.027 0.189 0.441 0.343

What is the variance of the distribution?

A) 2.100 B) 0.794 C) 6.440 D) 0.630

32) A farmer who grows genetically engineered corn is experiencing trouble with corn borers. A random check of 5,000 ears revealed the following: many of the ears contained no borers, some ears had one borer, a few had two borers, and so on. The distribution of the number of borers per ear approximated the Poisson distribution. The farmer counted 6,000 borers in the 5,000 ears. What is the probability that an ear of corn selected at random will contain no borers?

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A) 0.3012 B) 0.1131 C) 0.1522 D) 0.8046

33)

For a binomial distribution, the mean is 0.6 and n = 2. What is π for this distribution?

A) 0.3 B) 0.1 C) 1.00 D) 0.5

34) A machine shop has 100 drill presses and other machines in constant use. The probability that a machine will become inoperative during a given day is 0.002. During some days, no machines are inoperative, but on other days, one, two, three, or more are broken down. What is the probability that fewer than two machines will be inoperative during a particular day?

A) 0.9824 B) 0.0200 C) 0.8187 D) 0.1637

35)

For the following distribution: x 0 1 2 3 4

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P(x) 0.130 0.346 0.346 0.154 0.026

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What is the mean of the distribution?

A) 3.154 B) 2.521 C) 1.604 D) 1.346

36) Sponsors of a local charity decided to attract wealthy patrons to its $500-a-plate dinner by allowing each patron to buy a set of 20 tickets for the gaming tables. The chance of winning a prize for each of the 20 plays is 50–50. If you bought 20 tickets, what is the chance of winning 15 or more prizes?

A) 0.750 B) 0.250 C) 0.006 D) 0.021

37) David's gasoline station offers 4 cents off per gallon if the customer pays in cash and does not use a credit card. Past evidence indicates that 40% of all customers pay in cash. During a one-hour period, 15 customers buy gasoline at this station. What is the probability that at least 10 pay in cash?

A) 0.976 B) 0.024 C) 0.009 D) 0.033

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38) A new car was put into production. It involved many assembly tasks. Each car was inspected at the end of the assembly line and the number of defects per unit was recorded. For the first 100 cars produced, there were 40 defective cars. Some of the cars had no defects, a few had one defect, and so on. The distribution of defects followed a Poisson distribution. Based on the first 100 cars produced, about how many out of every 1,000 cars assembled should have one or more defects?

A) About 630 B) About 660 C) About 165 D) About 330

39)

For the following distribution. x 0 1 2 3

P(x) 0.027 0.189 0.441 0.343

What is the mean of the distribution?

A) 1.589 B) 2.603 C) 0.441 D) 2.100

40) The probability distribution for the number of automobiles lined up at a Lakeside Olds dealer at opening time (7:30 AM) for service is: Number 1 2 3 4

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Probability 0.20 0.25 0.45 0.10

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On a typical day, how many automobiles should Lakeside Olds expect to be lined up at opening time?

A) 2.51 B) 3.00 C) 2.45 D) 1.20

41)

If the variance is 4.1 grams, what is the standard deviation?

A) 11.000 B) 2.025 C) 16.810 D) 1.100

42) The random variable for a Poisson probability distribution can assume an infinite number of values. ⊚ true ⊚ false

43)

Which probability distribution should be used to solve the following problem?

A machine shop has 100 drill presses and other machines in constant use. The probability that a machine will become inoperative during a given day is 0.002. During some days, no machines are inoperative, but on other days, one, two, three, or more are broken down. What is the probability that fewer than two machines will be inoperative during a particular day?

A) Normal probability distribution B) Binomial probability distribution C) Poisson probability distribution D) Hypergeometric probability distribution

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44)

Which is true for a binomial distribution?

A) It approximates the Poisson distribution.

B) There are 10 or more possible outcomes.

C) The probability of success remains the same from trial to trial.

D) The value of π is equal to 1.50.

45) David's gasoline station offers 4 cents off per gallon if the customer pays in cash and does not use a credit card. Past evidence indicates that 40% of all customers pay in cash. During a one-hour period, 15 customers buy gasoline at this station. This situation is an example of what type of discrete probability distribution?

A) Continuous probability distribution B) Binomial probability distribution C) Poisson probability distribution D) Hypergeometric probability distribution

46) A coin is tossed three times. The following table summarizes the experiment. What is the following table called?

Number of Heads 0 1 2 3

Probability of the Outcome 1/8 = 0.125 3/8 = 0.375 3/8 = 0.375 1/8 = 0.125

A) Probability distribution B) Cumulative frequency distribution C) Frequency table D) Standard deviation

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47) A company is studying the number of monthly absences among its 125 employees. The following probability distribution shows the likelihood that people were absent 0, 1, 2, 3, 4, or 5 days last month.

Number of Days Absent 0 1 2 3 4 5

Probability 0.60 0.20 0.12 0.04 0.04 0.00

What is the standard deviation of the number of days absent?

A) 1.1616 B) 0 C) 1.0778 D) 1.6595

48) In the binomial probability formula, value. ⊚ ⊚

nC

xπ

x

(1 − π)

(n − x)

, C is equal to a constant

true false

49) To construct a binomial distribution, it is necessary to know the total number of trials and the probability of success on each trial. ⊚ true ⊚ false

50) An experiment consists of making 80 telephone calls in order to sell a particular insurance policy. The random variable in this experiment is a ___________.

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A) discrete random variable B) continuous random variable C) complex random variable D) simple random variable

51)

In the binomial probability formula, ⊚ ⊚

52)

nC

xπ

x

(1 − π)

(n − x)

, π is equal to 3.14159.

true false

The following is a binomial probability distribution with n = 3 and π = 0.20. x 0 1 2 3

P(x) 0.512 0.384 0.096 0.008

The mean of the distribution is _______.

A) 0.00 B) 1.50 C) 0.25 D) 0.60

53) A type of probability distribution that shows the probability of x successes in n trials, where the probability of success remains the same from trial to trial, is referred to as a ___________.

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A) normal probability distribution B) binomial probability distribution C) hypergeometric probability distribution D) uniform probability distribution

54)

Reference the following table: x 0 1 2 3 4

P(x) 0.130 0.346 0.346 0.154 0.026

What is the variance of the distribution?

A) 0.9643 B) 1.1616 C) 0.9820 D) 1.0000

55) On a very hot summer day, 5% of the production employees at Midland States Steel are absent from work. The production employees are randomly selected for a special in-depth study on absenteeism. What is the probability of randomly selecting 10 production employees on a hot summer day and finding that none of them are absent?

A) 0.100 B) 0.344 C) 0.599 D) 0.002

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56) Sweetwater & Associates write weekend trip insurance at a very nominal charge. Records show that the probability that a motorist will have an accident during the weekend and file a claim is 0.0005. Suppose they wrote 800 policies for the coming weekend, what is the probability that exactly two claims will be filed?

A) 0.0536 B) 0.4500 C) 0.6703 D) 0.0002

57) A statistics professor receives an average of five e-mail messages per day from students.

Assume the number of messages approximates a Poisson distribution. What is the probability that on a randomly selected day she will have no messages?

A) It is impossible to have no messages.

B) 0.0335 C) 0.0067 D) 0

58) A manufacturer of headache medicine claims it is 70% effective within a few minutes.

That is, out of every 100 users, 70 get relief within a few minutes. A group of 12 patients are given the medicine. If the claim is true, what is the probability that eight have relief within a few minutes?

A) 0.168 B) 0.001 C) 0.231 D) 0.667

59) A total of 60% of the customers of a fast-food chain order a hamburger, French fries, and a drink. If a random sample of 15 cash register receipts is selected, what is the probability that 10 or more will show that the above three food items were ordered?

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A) 0.403 B) 0.186 C) 1.000 D) 0.000

60)

The binomial probability distribution is always negatively skewed. ⊚ true ⊚ false

61) A measure of the long-run average value of a random variable used to represent the central location of a probability distribution is called a(n) _____________.

A) population variance B) coefficient of variation C) population standard deviation D) expected value

62)

The mean of a binomial distribution is the product of n and π. ⊚ true ⊚ false

63) A tennis match requires that a player win three of five sets to win the match. If a player wins the first two sets, what is the probability that the player wins the match, assuming that each player is equally likely to win each set?

A) 0.125 B) 0.875 C) 0.000 D) 0.500

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64)

The following is a Poisson probability distribution with µ = 0.1: x 0 1 2 3

P(x) 0.9048 0.0905 0.0045 0.0002

The variance of the distribution is ______.

A) 0.9046 B) 1.0 C) 0.1 D) 3.0

65) The production department has installed a new spray machine to paint automobile doors.

As is common with most spray guns, unsightly blemishes often appear because of improper mixtures or other problems. A worker counted the number of blemishes on each door. Most doors had no blemishes; a few had one; a very few had two; and so on. The average number was 0.5 per door. The distribution of blemishes followed the Poisson distribution. Out of 10,000 doors painted, about how many would have no blemishes?

A) About 500 B) About 5,000 C) About 6,065 D) About 3,935

66) A statistics professor receives an average of five e-mail messages per day from students.

Assume the number of messages approximates a Poisson distribution. What is the probability that on a randomly selected day she will have five messages?

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A) 1.0000 B) 0.8750 C) 0.0067 D) 0.1755

67)

To construct a binomial probability distribution, the mean must be known. ⊚ true ⊚ false

68) A company is studying the number of monthly absences among its 125 employees. The following probability distribution shows the likelihood that people were absent 0, 1, 2, 3, 4, or 5 days last month.

Number of Days Absent 0 1 2 3 4 5

Probability 0.60 0.20 0.12 0.04 0.04 0.00

Given the probability distribution, which of the following predictions is correct?

A) There is a 0.04 probability that an employee will be absent one day per month.

B) 60% of the employees will have more than one day absent per month.

C) There is a 0.12 probability that an employee will be absent two days per month.

D) There is a 0.50 probability that an employee will be absent 0.72 days per month.

69) Judging from recent experience, 5% of the computer keyboards produced by an automatic, high-speed machine are defective. If six keyboards are randomly selected, what is the probability that none of the keyboards are defective?

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A) 0.735 B) 0.500 C) 0.167 D) 0.001

70)

In the binomial probability formula,

nC

xπ

x

(1 − π)

(n − x)

, n represents:

A) the probability of failure on each trial.

B) the number of trials.

C) a combination.

D) the probability of success on each trial.

71)

What kind of distributions are the binomial and Poisson probability distributions?

A) Both discrete and continuous B) Neither discrete nor continuous C) Discrete D) Continuous

72) The variance of a probability distribution is based on the sum of squared differences from the mean multiplied by the probability of X. ⊚ true ⊚ false

73)

If the variance is 3.6 grams, what is the standard deviation?

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A) 1.897 B) 0.600 C) 6.000 D) 12.96

74) A farmer who grows genetically engineered corn is experiencing trouble with corn borers. A random check of 5,000 ears revealed the following: many of the ears contained no borers. some ears had one borer. A few had two borers, and so on. The distribution of the number of borers per ear approximated the Poisson distribution. The farmer counted 3,500 borers in the 5,000 ears. What is the probability that an ear of corn selected at random will contain no borers?

A) 1.000 B) 0.0631 C) 0.3476 D) 0.4966

75)

What must you know to develop a binomial probability distribution?

A) The probability of success and the number of trials B) The probability of success and the number of successes C) The probability of success D) The number of trials and the number of successes

76) A probability distribution is a mutually exclusive and collectively exhaustive listing of experimental outcomes that can occur by chance, and their corresponding probabilities. ⊚ true ⊚ false

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77)

The following is a Poisson probability distribution with µ = 0.1: x 0 1 2 3

P(x) 0.9048 0.0905 0.0045 0.0002

The mean of the distribution is _____.

A) 1.0 B) 1.5 C) 0.25 D) 0.1

78)

For a binomial distribution, the mean is 4.0 and n = 8. What is π for this distribution?

A) 4.0 B) 1.00 C) 0.1 D) 0.5

79)

The variance measures the skewness of a probability distribution. ⊚ true ⊚ false

80) An insurance agent has appointments with four prospective clients tomorrow. From past experience the agent knows that the probability of making a sale on any appointment is one out of five. Using the rules of probability, what is the likelihood that the agent will sell a policy to exactly three of the four prospective clients?

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A) 0.026 B) 0.500 C) 0.410 D) 0.250

81) Carlson Jewelers permits the return of their diamond wedding rings, provided the return occurs within two weeks of the purchase date. Their records reveal that 10% of the diamond wedding rings are returned. Five different customers buy a wedding ring. What is the probability that none of the customers return a ring?

A) 0.073 B) 0.500 C) 0.250 D) 0.590

82) A listing of all possible outcomes of an experiment and their corresponding probabilities of occurrence is called a ____________.

A) random variable B) frequency distribution C) subjective probability D) probability distribution

83)

The variance of a binomial distribution is found by nπ(1 − π). ⊚ true ⊚ false

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84) The marketing department of a nationally known cereal maker plans to conduct a national survey to find out whether or not consumers of flake cereals can distinguish one of their favorite flake cereals. To test the questionnaire and procedure to be used, eight persons were asked to cooperate in an experiment. Five very small bowls of flake cereals were placed in front of a person. The bowls were labeled A, B, C, D, and E. The person was informed that only one bowl contained his or her favorite flake cereal. Suppose that the eight persons in the experiment were unable to identify their favorite cereal and just guessed which bowl it was in. What is the probability that none of the eight guessed correctly?

A) 0.009 B) 0.168 C) 0.788 D) 0.125

85) The probability distribution for the number of automobiles lined up at a Lakeside Olds dealer at opening time (7:30 AM) for service is: Number 1 2 3 4

Probability 0.05 0.30 0.40 0.25

On a typical day, how many automobiles should Lakeside Olds expect to be lined up at opening time?

A) 1.96 B) 1.00 C) 2.85 D) 10.00

86) David's gasoline station offers 4 cents off per gallon if the customer pays in cash and does not use a credit card. Past evidence indicates that 40% of all customers pay in cash. During a one-hour period, 15 customers buy gasoline at this station. What is the probability that all 15 pay in cash?

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A) 1.000 B) 0.100 C) 0.900 D) 0.000

87)

The following is a Poisson probability distribution with µ = 0.5: x 0 1 2 3

P(x) 0.9040 0.0885 0.0065 0.0010

The mean of the distribution is _____.

A) 0.65 B) 1.50 C) 0.50 D) 1.00

88)

The probability of a particular outcome must always be between 0.0 and 1.0 inclusive. ⊚ true ⊚ false

89) David's gasoline station offers 4 cents off per gallon if the customer pays in cash and does not use a credit card. Past evidence indicates that 40% of all customers pay in cash. During a one-hour period, 15 customers buy gasoline at this station. What is the probability that more than 8 and less than 12 customers pay in cash?

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A) 0.562 B) 0.210 C) 0.212 D) 0.092

90)

For the following distribution: x 0 1 2 3

P(x) 0.900 0.09 0.007 0.003

What is the variance of the distribution?

A) 0.132 B) 0.113 C) 0.364 D) 2.100

91)

Reference the following table: x 0 1 2 3 4

P(x) 0.170 0.306 0.306 0.114 0.104

What is the variance of the distribution?

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A) 1.2416 B) 0.9020 C) 1.4110 D) 1.0000

92)

To apply a Poisson probability distribution, the mean can be computed as __________.

A) B) e −x C) nπ D)

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Answer Key Test name: Chap 06_10e_Lind 1) D 2) B 3) D 4) C 5) C 6) A 7) C 8) C 9) TRUE 10) D 11) A 12) A 13) D 14) D 15) C 16) B 17) A 18) B 19) B 20) B 21) FALSE 22) C 23) D 24) B 25) D 26) B Version 1

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27) A 28) B 29) TRUE 30) A 31) D 32) A 33) A 34) A 35) C 36) D 37) D 38) D 39) D 40) C 41) B 42) TRUE 43) C 44) C 45) B 46) A 47) C 48) FALSE 49) TRUE 50) A 51) FALSE 52) D 53) B 54) A 55) C 56) A Version 1

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57) C 58) C 59) A 60) FALSE 61) D 62) TRUE 63) B 64) C 65) C 66) D 67) FALSE 68) C 69) A 70) B 71) C 72) TRUE 73) A 74) D 75) A 76) TRUE 77) D 78) D 79) FALSE 80) A 81) D 82) D 83) TRUE 84) B 85) C 86) D Version 1

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87) C 88) TRUE 89) D 90) A 91) C 92) C

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CHAPTER 7 1)

Which of the following is a characteristic of the normal probability distribution?

A) It is asymmetrical.

B) It is rectangular.

C) It is bell-shaped.

D) It is positively skewed.

2) Management is considering a bonus system to increase production. One suggestion is to pay a bonus on the highest 5% of production based on past experience. Past records indicate that an average of 4,000 units of a small assembly is produced during a week. The distribution of the weekly production is approximately normally distributed with a standard deviation of 60 units. If the bonus is paid on the upper 5% of production, the bonus will be paid on how many units or more?

A) 3,196 B) 4,099 C) 5,120 D) 6,255

3) The seasonal output of a new experimental strain of pepper plants was carefully weighed.

The mean weight per plant is 15.0 pounds, and the standard deviation of the normally distributed weights is 1.75 pounds. Of the 200 plants in the experiment, how many produced peppers weighing between 13 and 16 pounds?

A) 53 B) 197 C) 100 D) 118

4) The mean of a normal probability distribution is 500 and the standard deviation is 10.

About 95% of the observations lie between what two values?

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A) 475 and 525 B) 480 and 520 C) 350 and 650 D) 400 and 600

5) The mean of a normal distribution is 400 pounds. The standard deviation is 10 pounds.

What is the probability of a weight between 415 pounds and the mean of 400 pounds?

A) 0.1932 B) 0.4332 C) 0.5000 D) 0.3413

6) The time to fly between New York City and Chicago is uniformly distributed with a minimum of 120 minutes and a maximum of 150 minutes. What is the distribution's mean?

A) 270 minutes B) 135 minutes C) 120 minutes D) 150 minutes

7) Consider a standard normal random variable z. What is the value of z if the area to the right of z is 0.2643?

A) 0.72 B) 0.63 C) 1.46 D) 0.28

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8) The time to fly between New York City and Chicago is uniformly distributed with a minimum of 96 minutes and a maximum of 100 minutes. What is the probability that a flight is between 97 and 98 minutes?

A) 0.17 B) 1.00 C) 0.83 D) 0.25

9) The weekly mean income of a group of executives is $1,000 and the standard deviation of this group is $100. The distribution is normal. What percent of the executives have an income of $925 or less?

A) 22.66% B) 27.34% C) 7.5% D) 77.34%

10) A national manufacturer of unattached garages discovered that the distribution of the time for two construction workers to erect the Red Barn model is normally distributed with a mean of 32 hours and a standard deviation of 2 hours. What percent of the garages take between 32 and 34 hours to erect?

A) 3.14% B) 16.29% C) 34.13% D) 76.71%

11) The average score of 100 students taking a statistics final was 70 with a standard deviation of 7. Assuming a normal distribution, what is the probability that a student scored greater than 65?

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A) 0.2389 B) −0.714 C) 0.7611 D) 0.2611

12) The employees of Cartwright Manufacturing are awarded efficiency ratings. The distribution of the ratings approximates a normal distribution. The mean is 400, the standard deviation is 50. What is the area under the normal curve between 400 and 482?

A) 0.5000 B) 0.4750 C) 0.4495 D) 0.3413

13) The weekly incomes of a large group of executives are normally distributed with a mean of $2,000 and a standard deviation of $100. What is the z-score for an income of $2,100?

A) −0.900 B) +1.683 C) +1.000 D) +2.000

14) What is an important similarity between the uniform and normal probability distributions?

A) The mean, median, and mode are all equal.

B) About 68% of all observations are within one standard deviation of the mean.

C) They are negatively skewed.

D) The mean and median are equal.

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15) The mean score of a college entrance test is 500; the standard deviation is 75. The scores are normally distributed. What percent of the students scored below 320?

A) About 34.13% B) About 0.82% C) About 7.86% D) About 50.82%

16) Ball-Bearings, Incorporated produces ball bearings automatically on a Kronar BBX machine. For one of the ball bearings, the mean diameter is set at 20.00 mm (millimeters). The standard deviation of the production over a long period of time was computed to be 0.150 mm.

What percent of the ball bearings will have diameters of 20.27 mm or more?

A) 41.00% B) 85.00% C) 12.62% D) 3.59%

17)

The number of different standard normal distributions is unlimited. ⊚ true ⊚ false

18) Customers of the Key Refining Company charge an average of $70 per month. The distribution of amounts charged is approximately normal, with a standard deviation of $10. What is the probability of selecting a credit card customer at random and finding the customer charged between $70 and $83?

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A) 0.4032 B) 0.4750 C) 0.3413 D) 0.1962

19) For the normal distribution, the mean plus and minus two standard deviations will include about what percent of the observations?

A) 99.7% B) 50% C) 68% D) 95%

20) The time to fly between New York City and Chicago is uniformly distributed with a minimum of 120 minutes and a maximum of 150 minutes. What is the probability that a flight is less than 135 minutes?

A) 0 B) 0.25 C) 1.00 D) 0.50

21) Consider a continuous random variable x, which is uniformly distributed between 65 and 85. The probability of x taking on a value between 75 to 90 is ________.

A) 1.00 B) 0.75 C) 0.075 D) 0.50

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22) An analysis of the grades on the first test in History 101 revealed that they approximate a normal curve with a mean of 75 and a standard deviation of 8. The instructor wants to award the grade of A to the upper 10% of the test grades. To the nearest percent, what is the dividing point between an A and a B grade?

A) 80 B) 90 C) 85 D) 95

23) A study of a company's practice regarding the payment of invoices revealed that an invoice was paid an average of 20 days after it was received. The standard deviation equaled five days. Assuming that the distribution is normal, what percent of the invoices were paid within 15 days of receipt?

A) 37.91% B) 34.13% C) 15.87% D) 86.74%

24) The annual commissions per salesperson employed by a retailer of mobile communication devices averaged $40,400, with a standard deviation of $5,000. What percent of the salespersons earn between $32,000 and $42,000?

A) 36.29% B) 79.50% C) 42.10% D) 57.90%

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25) Suppose a tire manufacturer wants to set a mileage guarantee on its new XB 70 tire. Tests revealed that the tire's mileage is normally distributed with a mean of 49,500 miles and a standard deviation of 2,050 miles. The manufacturer wants to set the guaranteed mileage so that no more than 5% of the tires will have to be replaced. What guaranteed mileage should the manufacturer announce?

A) 42,522 B) 34,560 C) 51,221 D) 46,118

26)

For a uniformly distributed random variable, x, P(x) is constant. ⊚ true ⊚ false

27) Nonstop Airlines determined that the mean number of passengers per flight is 152 with a standard deviation of 10 passengers. Practically all flights have between 142 and 162 passengers. ⊚ true ⊚ false

28) The average starting salary of individuals with a master's degree in statistics is normally distributed with a mean of $48,000 and a standard deviation of $6,000. What is the probability that a randomly selected individual with a master's in statistics will get a starting salary of at least $55,000?

A) 0.891 B) 0.098 C) 0.379 D) 0.121

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29) Over the last year, customers who have phoned their cable company for technical support have had to wait for a customer service representative an average of 28 minutes, with a standard deviation of 5.5 minutes. Company records have shown wait times to be normally distributed.

What is the likelihood that a person phones the cable company and waits between 10 to 20 minutes for service?

A) 12.3% B) 4.3% C) 7.24% D) .01%

30) A college professor noted that the grades of his students in an introductory statistics class were normally distributed with a mean of 58.50 and a standard deviation of 9. If 67.70% of his students received grades of C or above, what is the minimum score of those students receiving a grade of at least a C? A) 67.70 B) 54.36 C) 51.91 D) 48.47

31) A large manufacturing firm tests job applicants. Test scores are normally distributed with a mean of 500 and a standard deviation of 50. Management is considering placing a new hire in an upper-level management position if the person scores in the upper sixth percent of the distribution. What is the lowest score a new hire must earn to qualify for a responsible position?

A) 460 B) 625 C) 50 D) 578

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32) The annual commissions per salesperson employed by a retailer of mobile communication devices averaged $40,000, with a standard deviation of $5,000. What percent of the salespersons earn between $32,000 and $42,000?

A) 81.66% B) 34.13% C) 60.06% D) 39.94%

33) When referring to the normal probability distribution, there is not just one; there is a "family" of normal probability distributions. ⊚ true ⊚ false

34) The average score of 100 students taking a statistics final was 70, with a standard deviation of 7. Assuming a normal distribution, what test score separates the top 5% of the students from the lower 95% of the students?

A) 81.55 B) 78.96 C) 90.00 D) 83.72

35) The average starting salary of individuals with a master's degree in statistics is normally distributed with a mean of $58,200 and a standard deviation of $6,000. What is the probability that a randomly selected individual with a master's in statistics will get a starting salary of at least $68,600?

A) 0.019 B) 0.970 C) 0.042 D) 0.458

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36) The average score of 100 students taking a statistics final was 70 with a standard deviation of 7. Assuming a normal distribution, what test score separates the top 25% of the students from the lower 75% of students?

A) 75.25 B) 74.69 C) 70.00 D) 65.31

37) The time to fly between New York City and Chicago is uniformly distributed with a minimum of 120 minutes and a maximum of 150 minutes. What is the distribution's standard deviation?

A) 8.66 minutes B) 135 minutes C) 270 minutes D) 75 minutes

38) Within plus and minus one standard deviation of the mean, the area under any normal curve is about 68%. ⊚ true ⊚ false

39)

The z-value for a standard normal distribution ________.

A) is always equal to the value of the population mean B) is always positive C) can be either positive or negative D) is always equal to zero

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40) The time to fly between New York City and Chicago is uniformly distributed with a minimum of 120 minutes and a maximum of 150 minutes. What is the probability that a flight is more than 140 minutes?

A) 0.333 B) 0.067 C) 0.500 D) 1.000

41)

The standard normal probability distribution is unique because it has _________.

A) any mean and a standard deviation of 1 B) a mean of 1 and any standard deviation C) a mean of 0 and a standard deviation of 1 D) a mean of 0 and any standard deviation

42) The average score of 100 students taking a statistics final was 70, with a standard deviation of 7. Assuming a normal distribution, what is the probability that a student scored 90 or higher?

A) 2.8600 B) 0.0021 C) 0.4979 D) 0.9979

43)

The mean of any uniform probability distribution is _________.

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A) (a + b)/2 B) (b − a)/2 C) ∑ </em></p> D) nπ

44) The weight of cans of fruit is normally distributed with a mean of 1,000 grams and a standard deviation of 50 grams. What percent of the cans weigh 860 grams or less?

A) 26.00% B) 0.50% C) 0.26% D) 49.74%

45) Over the last year, customers who have phoned their cable company for technical support have had to wait for a customer service representative an average of 28 minutes, with a standard deviation of 5.5 minutes. Company records have shown wait times to be normally distributed.

What is the likelihood that a person phones the cable company and waits more than 30 minutes for service?

A) .5541 B) .3581 C) .6212 D) .0382

46) The standard normal distribution is a special normal distribution with a mean of 0 and a standard deviation of 1. ⊚ true ⊚ false

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47)

Some normal probability distributions are positively skewed. ⊚ true ⊚ false

48) The average score of 100 students taking a statistics final was 76 with a standard deviation of 7. Assuming a normal distribution, what is the probability that a student scored greater than 67?

A) 0.0985 B) 0.9015 C) 0.4015 D) −1.286

49) The distribution of the annual incomes of a group of middle management employees approximated a normal distribution with a mean of $37,200 and a standard deviation of $800.

About 68.26% of the incomes lie between what two incomes?

A) $30,000 and $40,000 B) $36,400 and $38,000 C) $34,800 and $39,600 D) $35,600 and $38,800

50)

The total area of a normal probability distribution is _______.

A) dependent on a value of z B) approximated by the binomial distribution C) between −3.0 and 3.0 D) 1.00

51)

For a standard normal distribution, what is the probability that z is greater than 1.75?

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A) 0.0401 B) 0.9599 C) 0.4599 D) 0.0459

52)

Which of the following is true regarding the normal distribution?

A) The points of the curve meet the X-axis at z = −3 and z = 3.

B) It has two modes.

C) The mean, median, and mode are all equal.

D) It is asymmetrical.

53) The time to fly between New York City and Chicago is uniformly distributed with a minimum of 120 minutes and a maximum of 150 minutes. What is the probability that a flight is between 125 and 140 minutes?

A) 1.00 B) 0.33 C) 0.67 D) 0.50

54) A new extended-life lightbulb has an average life of 750 hours, with a standard deviation of 50 hours. If the life of these lightbulbs approximates a normal distribution, about what percent of the distribution will be between 600 hours and 900 hours?

A) 99.74% B) 34% C) 68% D) 95%

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55)

Which of the following is true in a normal distribution?

A) The area under the curve is 0.68.

B) The mean equals zero.

C) The mean divides the distribution into two equal areas.

D) The mode and the third quartile are equal.

56) For any uniform probability distribution, the mean and standard deviation can be computed based on the maximum and minimum values of the random variable. ⊚ true ⊚ false

57) Two normal distributions are compared. One has a mean of 10 and a standard deviation of 10. The second normal distribution has a mean of 10 and a standard deviation of 2. Which of the following is true?

A) The distributions are from two different families of distributions.

B) The locations of the distributions are different.

C) The dispersions of the distributions are the same.

D) The dispersions of the distributions are different.

58) Over the last year, customers who have phoned their cable company for technical support have had to wait for a customer service representative an average of 28 minutes, with a standard deviation of 5.5 minutes. Company records have shown wait times to be normally distributed.

What is the likelihood that a person phones the cable company and gets service in less than 10 minutes?

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A) 0.05% B) 12.3% C) 4.3% D) 7.4%

59)

The center of a normal probability distribution is ________.

A) the mean of the distribution B) never negative C) the same as the standard deviation or the distribution D) always equal to zero

60)

What is the probability that z is between 0.0 and 2.0?

A) 0.1359 B) 0.7408 C) 0.4772 D) 1.0000

61) Over the last year, customers who have phoned their cable company for technical support have had to wait for a customer service representative an average of 28 minutes, with a standard deviation of 5.5 minutes. Company records have shown wait times to be normally distributed.

What is the likelihood that a person phones the cable company and gets service in exactly 15.25 minutes?

A) .01% B) 0% C) 12.3% D) 7.4%

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62)

For a uniformly distributed random variable, x, P(x) = 1/(b − a). ⊚ true ⊚ false

63)

The upper and lower limits of a uniform probability distribution are __________.

A) positive and negative infinity B) plus and minus three standard deviations C) 0 and 1 D) the maximum and minimum values of the random variable

64) The time to fly between New York City and Chicago is uniformly distributed with a minimum of 88 minutes and a maximum of 100 minutes. What is the probability that a flight is less than 89 minutes?

A) 0.04 B) 1.00 C) 0.08 D) 0

65)

The z-scores for X values greater than the mean are negative. ⊚ true ⊚ false

66) Consider a standard normal random variable z. What is the value of z if the area to the right of z is 0.3632?

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A) 0.38 B) 0.35 C) 0.90 D) 0.44

67)

What is the area under the normal curve between z = 0.0 and z = 1.79?

A) 0.0367 B) 0.4633 C) 0.0401 D) 0.9599

68) The mean amount spent by a family of four on food is $500 per month with a standard deviation of $75. Assuming that the food costs are normally distributed, what is the probability that a family spends less than $410 per month?

A) 0.8750 B) 0.0362 C) 0.2158 D) 0.1151

69) A cola-dispensing machine is set to dispense a mean of 2.02 liters into a container labeled 2 liters. Actual quantities dispensed vary, and the amounts are normally distributed with a standard deviation of 0.015 liters. What is the probability a container will have less than 2 liters?

A) 0.1926 B) 0.3413 C) 0.0918 D) 0.8741

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70) The time to fly between New York City and Chicago is uniformly distributed with a minimum of 95 minutes and a maximum of 125 minutes. What is the distribution's mean?

A) 125 minutes B) 220 minutes C) 110 minutes D) 95 minutes

71) A college professor noted that the grades of his students in an introductory statistics class were normally distributed with a mean of 76.5 and a standard deviation of 9. If 67.36% of his students received grades of C or above, what is the minimum score of those students receiving a grade of at least a C? A) 72.45 B) 67.36 C) 66.56 D) 70.00

72)

In an illustration of a normal probability distribution, a shaded area represents _______.

A) a permutation B) a standard deviation C) a combination D) a probability

73)

The standard deviation of any uniform probability distribution is ____________.

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A) ∑ B) C) (b − a)/2 D) n(1 − π)

74) The average score of 100 students taking a statistics final was 58 with a standard deviation of 7. Assuming a normal distribution, what test score separates the top 25% of the students from the lower 75% of students?

A) 58.00 B) 62.69 C) 63.25 D) 63.25 E) 77.31

75) Over the last year, customers who have phoned their cable company for technical support have had to wait for a customer service representative an average of 28 minutes, with a standard deviation of 5.5 minutes. Company records have shown wait times to be normally distributed. If the cable company wants to make a guaranteed promise that customers will get a free month of cable if they wait more than x minutes, and the company is willing to be wrong only 5% of the time, what promise, in minutes, should they make?

A) 37 minutes B) 34 minutes C) 28 minutes D) 14 minutes

76)

What is a normal distribution with a mean of 0 and a standard deviation of 1 called?

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A) Standard normal distribution B) Frequency distribution C) Binomial probability distribution D) Z-score

77)

The shape of any uniform probability distribution is ____________.

A) bell-shaped B) negatively skewed C) positively skewed D) rectangular

78)

What is the area under the normal curve between z = −1.0 and z = −2.0?

A) 0.0228 B) 0.1359 C) 0.3413 D) 0.4772

79) Suppose a tire manufacturer wants to set a mileage guarantee on its new XB 70 tire. Tests revealed that the tire's mileage is normally distributed with a mean of 47,900 miles and a standard deviation of 2,050 miles. The manufacturer wants to set the guaranteed mileage so that no more than 5% of the tires will have to be replaced. What guaranteed mileage should the manufacturer announce?

A) 44,518 B) 40,922 C) 49,621 D) 32,960

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80) An accelerated life test on a large number of type-D alkaline batteries revealed that the mean life for a particular use before they failed is 19.0 hours. The distribution of the lives approximated a normal distribution. The standard deviation of the distribution was 1.2 hours.

About 95.44% of the batteries failed between what two values?

A) 8.9 and 18.9 B) 12.2 and 14.2 C) 14.1 and 22.1 D) 16.6 and 21.4

81) For a normal distribution, what is the likelihood (expressed as a percentage) that a random variable is within plus and minus two standard deviations of the mean?

A) 99.74% B) 34.13% C) 95.44% D) 68.26%

82) Tables of normal distribution probabilities are found in many statistics books. These probabilities are calculated from astandardized normal distribution with ___________.

A) a mean of 0 and a standard deviation of 15 B) a mean of 0 and a standard deviation of 1 C) a mean of 100 and a standard deviation of 15 D) a mean of 1 and a standard deviation of 1

83)

A normally distributed random variable has _________.

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A) any value between −∞ and +∞ B) only two values, success and failure C) any value between specified minimum and maximum values D) discrete values

84) A group of normal distributions can have equal arithmetic means but different standard deviations. ⊚ true ⊚ false

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Answer Key Test name: Chap 07_10e_Lind 1) C 2) B 3) D 4) B 5) B 6) B 7) B 8) D 9) A 10) C 11) C 12) C 13) C 14) D 15) B 16) D 17) FALSE 18) A 19) D 20) D 21) D 22) C 23) C 24) D 25) D 26) TRUE Version 1

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27) FALSE 28) D 29) C 30) B 31) D 32) C 33) TRUE 34) A 35) C 36) B 37) A 38) TRUE 39) C 40) A 41) C 42) B 43) A 44) C 45) B 46) TRUE 47) FALSE 48) B 49) B 50) D 51) A 52) C 53) D 54) A 55) C 56) TRUE Version 1

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57) D 58) A 59) A 60) C 61) B 62) TRUE 63) D 64) C 65) FALSE 66) B 67) B 68) D 69) C 70) C 71) A 72) D 73) B 74) B 75) A 76) A 77) D 78) B 79) A 80) D 81) C 82) B 83) A 84) TRUE

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CHAPTER 8 1) To study the population of consumer perceptions of new technology, sampling of the population is preferred over surveying the entire population because ______.

A) sampling is more accurate B) sampling methods are simple C) it is quicker D) we can compute z-scores

2)

Ethical research methods include A) always using a census as samples as not reliable.

B) doing your best to select an unbiased sample.

C) using only convenience sampling to select samples.

D) selecting samples that you know to be biased.

3) The tread life of tires mounted on light-duty trucks follows the normal probability distribution with a population mean of 60,000 miles and a population standard deviation of 4,000 miles. Suppose we select a sample of 40 tires and use a simulator to determine the tread life.

What is the standard error of the mean?

A) 4,000 B) 632.46 C) Cannot be determined.

D) 40

4) The wildlife department has been feeding a special food to rainbow trout fingerlings in a pond. Based on a large number of observations, the distribution of trout weights is normally distributed with a mean of 402.7 grams and a standard deviation of 10.8 grams. What is the probability that the mean weight for a sample of 43 trout exceeds 405.5 grams?

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A) 1.0 B) 0.4006 C) 0.0446 D) 0.5

5)

How many different samples of size 4 can be selected from a population of size 8?

A) 8 B) 32 C) 70 D) 1,680

6) The standard error of the mean measures the dispersion of the sampling distribution of the sample mean. ⊚ true ⊚ false

7) The Office of Student Services at a large western state university maintains information on the study habits of its full-time students. Their studies indicate that the mean amount of time undergraduate students study per week is 20 hours. The hours studied follows the normal distribution with a population standard deviation of 18 hours. Suppose we select a random sample of 400 current students. What is the standard error of the mean?

A) 0.90 B) 18.00 C) 2.40 D) 0.65

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8) The BLS employer cost survey uses a sample to establish the average wage of receptionists. Based on a large number of observations, the distribution of receptionist wages is normally distributed with a mean $10.38 and a standard deviation of $2.05. What is the probability that the wages for a sample of 20 receptionists are between $8/hour and $11/hour?

A) 0.5498 B) 0.0881 C) 0.9119 D) 0.0000

9) A marketing firm is studying consumer preferences for winter fashions in four different months. From a population of women 18 to 21 years of age, a random sample of 100 women was selected in January. Another random sample of 100 women was selected in March. Another random sample of 100 women was selected in June. Another random sample of 100 women was selected in September. What is the sample size?

A) 4 B) 100 C) 1 D) 400

10) The wildlife department has been feeding a special food to rainbow trout fingerlings in a pond. Based on a large number of observations, the distribution of trout weights is normally distributed with a mean of 402.7 grams and a standard deviation of 8.8 grams. What is the probability that the mean weight for a sample of 40 trout exceeds 405.5 grams?

A) 0.0222 B) 0.3782 C) 0.5 D) 1.0

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11) Bones Brothers & Associates prepare individual tax returns. Over prior years, Bones Brothers has maintained careful records regarding the time to prepare a return. The mean time to prepare a return is 90 minutes, and the population standard deviation of this distribution is 11 minutes. Suppose 100 returns from this year are selected and analyzed regarding the preparation time. What is the standard error of the mean?

A) 1.1 minutes B) 110 minutes C) 11 minutes D) 90 minutes

12) <p>For a given population with a normal probability distribution, the sampling distribution of is a normal probability distribution for ________.

A) any sample size B) large sample sizes only C) sample sizes greater than 30 only D) small sample sizes only

13) Based on the central limit theorem, the sample mean can be used as a good estimator of the population mean, assuming that the size of the sample is sufficiently large. ⊚ true ⊚ false

14) The Intelligence Quotient (IQ) test scores for adults are normally distributed with a population mean of 100 and a population standard deviation of 15. What is the probability we could select a sample of 50 adults and find that the mean of this sample is between 98 and 103?

A) 0.3264 B) 0.9428 C) 0.4702 D) 0.7471

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15) For a population that is not normally distributed, the distribution of the sample means will ______ as the size of the sample increases.

A) approach a normal distribution B) be negatively skewed C) be positively skewed D) take the same shape as the population

16) The tread life of tires mounted on light-duty trucks follows the normal probability distribution with a population mean of 60,000 miles and a population standard deviation of 4,000 miles. Suppose you bought a set of four tires, what is the likelihood the mean tire life of these four tires is between 57,000 and 63,000 miles?

A) 0.5668 B) 0.4332 C) 0.8664 D) 0.9332

17)

The size of the standard error is ______.

A) inversely related to the sample size—in other words, the larger the sample size, the smaller the standard error B) directly related to the sample size—in other words, the larger the sample size, the larger the standard error C) directly related to the population mean—in other words, the larger the mean, the larger the standard error D) inversely related to the population standard deviation—in other words, the smaller the standard deviation, the larger the standard error

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18) Bones Brothers & Associates prepare individual tax returns. Over prior years, Bones Brothers has maintained careful records regarding the time to prepare a return. The mean time to prepare a return is 90 minutes, and the population standard deviation of this distribution is 14 minutes. Suppose 100 returns from this year are selected and analyzed regarding the preparation time. What is the probability that the mean time for the sample of 100 returns for this year is greater than 92?

A) 0.0832 B) 0.0764 C) 0.4168 D) Approximately 0

19)

Suppose we select every fifth invoice in a file. What type of sampling is this?

A) Stratified B) Random C) Cluster D) Systematic

20) If the sampling distribution of the sample means approximates a normal distribution, then the population must be normally distributed. ⊚ true ⊚ false

21) Suppose a research firm conducted a survey to determine the mean amount steady smokers spend on cigarettes during a week. A sample of 100 steady smokers revealed that the sample mean is $20. The population standard deviation is $5. What is the probability that a sample of 100 steady smokers spend between $19 and $21?

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A) 0.0228 B) 1.0000 C) 0.4772 D) 0.9544

22) The Intelligence Quotient (IQ) test scores for adults are normally distributed with a population mean of 100 and a population standard deviation of 20. What is the probability we could select a sample of 90 adults and find the mean of this sample is between 95 and 105?

A) 0.9822 B) 0.2587 C) near zero D) 0.0178

23) An experiment involves selecting a random sample of 256 middle managers for study.

One item of interest is their annual incomes. The sample mean is computed to be $35,420.00. If the population standard deviation is $2,050.00, what is the standard error of the mean?

A) $2,050.00 B) $128.13 C) $8.01 D) $138.36

24) The Intelligence Quotient (IQ) test scores for adults are normally distributed with a population mean of 100 and a population standard deviation of 15. What is the probability we could select a sample of 50 adults and find the mean of this sample is between 95 and 105?

A) 0.0182 B) near zero C) 0.9818 D) 0.2586

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25)

Sampling error is defined as ______.

A) N − n B) σ/n C) σ D)

26) For the sampling distribution of sample means, standard error will decrease as sample size increases. ⊚ true ⊚ false

27) Suppose a research firm conducted a survey to determine the mean amount steady smokers spend on cigarettes during a week. A sample of 120 steady smokers revealed that the sample mean is $20. The population standard deviation is $6. What is the probability that a sample of 120 steady smokers spend between $19 and $21?

A) 0.9328 B) 0.0336 C) 0.4664 D) 1.0000

28)

According to the central limit theorem, ______.

A) the population mean and the mean of all sample means are equal B) the sampling distribution of the sample means is approximately normally distributed C) the sampling distribution of the sample means will be skewed D) increasing sample size decreases the dispersion of the sampling distribution

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29) The Office of Student Services at a large western state university maintains information on the study habits of its full-time students. Their studies indicate that the mean amount of time undergraduate students study per week is 20 hours. The hours studied follows the normal distribution with a population standard deviation of six hours. Suppose we select a random sample of 144 current students. What is the probability that the mean of this sample is between 19.25 hours and 21.0 hours?

A) 0.0986 B) 0.9104 C) 0.9544 D) 0.0160

30) When deciding to collect sample information rather than collecting information from the population, the amount of time required to collect the information is unimportant. ⊚ true ⊚ false

31) We can expect some difference between sample statistics and the corresponding population parameters. This difference is called the sampling error. ⊚ true ⊚ false

32)

The standard error of the mean is also called the sampling error. ⊚ true ⊚ false

33) The BLS uses sampling for its National Compensation Survey to report employment costs. In its second stage of sampling, it divides employers by size. What type of sampling is this?

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A) Random B) Systematic C) Cluster D) Stratified

34) The central limit theorem allows us to use a z-statistic to compute probabilities for the sampling distribution of the sample mean. ⊚ true ⊚ false

35) The Office of Student Services at a large western state university maintains information on the study habits of its full-time students. Their studies indicate that the mean amount of time undergraduate students study per week is 20 hours. The hours studied follows the normal distribution with a population standard deviation of eight hours. Suppose we select a random sample of 185 current students. What is the probability that the mean of this sample is between 19.25 hours and 21.0 hours?

A) 0.1329 B) 0.8543 C) 0.9108 D) 0.0503

36) When doing research, knowing the population mean and other population parameters is essential. ⊚ true ⊚ false

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37) Bones Brothers & Associates prepare individual tax returns. Over prior years, Bones Brothers has maintained careful records regarding the time to prepare a return. The mean time to prepare a return is 90 minutes, and the population standard deviation of this distribution is 14 minutes. Suppose 100 returns from this year are selected and analyzed regarding the preparation time. What is the standard error of the mean?

A) 140 minutes B) 14 minutes C) 90 minutes D) 1.4 minutes

38) The Office of Student Services at a large western state university maintains information on the study habits of its full-time students. Their studies indicate that the mean amount of time undergraduate students study per week is 20 hours. The hours studied follows the normal distribution with a population standard deviation of six hours. Suppose we select a random sample of 144 current students. What is the probability that the mean of this sample is less than 19.25 hours?

A) 0.8664 B) 0.0668 C) 0.0181 D) 0.4332

39) When all the items in a population have an equal chance of being selected for a sample, the process is called ______.

A) z-score B) sampling error C) nonprobability sampling D) simple random sampling

40) All possible samples of size n are selected from a population, and the mean of each sample is determined. What is the mean of the sample means?

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A) It cannot be estimated in advance.

B) It is smaller than the population mean.

C) It is larger than the population mean.

D) It is the population mean.

41)

Which of the following is the standard error of the mean?

A) x/n B) σ C) D) s

42) The items or individuals of the population are arranged in a file drawer alphabetically by date received. A random starting point is selected and then every kth member of the population is selected for the sample. This sampling method is called systematic random sampling. ⊚ true ⊚ false

43) The Intelligence Quotient (IQ) test scores for adults are normally distributed with a population mean of 100 and a population standard deviation of 15. What is the probability we could select a sample of 50 adults and find that the mean of this sample exceeds 104?

A) 0.1064 B) 0.1064 C) 0.9706 D) 0.9412 E) 0.9706 F) 0.0294

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44) Bones Brothers & Associates prepare individual tax returns. Over prior years, Bones Brothers has maintained careful records regarding the time to prepare a return. The mean time to prepare a return is 90 minutes, and the population standard deviation of this distribution is 16 minutes. Suppose 100 returns from this year are selected and analyzed regarding the preparation time. What is the probability that the mean time for the sample of 100 returns is between 88 minutes and 92 minutes?

A) 0.1956 B) 0.7888 C) Approximately 1 D) 0.7752

45) For a distribution of sample means constructed by sampling 5 items from a population of 15, ______.

A) the sample size is 15 B) the mean of the sample means will be 3 C) the standard error will be 1 D) there will be 3,003 possible sample means

46) A marketing firm is studying consumer preferences for winter fashions in four different months. From a population of women 18 to 21 years of age, a random sample of 100 women was selected in January. Another random sample of 100 women was selected in March. Another random sample of 100 women was selected in June. Another random sample of 100 women was selected in September. What is the number of samples?

A) 1 B) 400 C) 4 D) 100

47)

When using stratified random sampling, the sampling error will be zero.

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⊚ ⊚

true false

48) The tread life of tires mounted on light-duty trucks follows the normal probability distribution with a population mean of 60,000 miles and a population standard deviation of 4,000 miles. Suppose you bought a set of four tires; what is the likelihood the mean tire life of these four tires is more than 66,000 miles?

A) 0.9544 B) 0.4987 C) 0.9987 D) 0.0013

49)

How many different samples of size 5 can be selected from a population of size 7?

A) 21 B) 504 C) 7 D) 35

50) Bones Brothers & Associates prepare individual tax returns. Over prior years, Bones Brothers has maintained careful records regarding the time to prepare a return. The mean time to prepare a return is 90 minutes, and the population standard deviation of this distribution is 14 minutes. Suppose 100 returns from this year are selected and analyzed regarding the preparation time. What is the probability that the mean time for the sample of 100 returns is between 88 minutes and 92 minutes?

A) 0.8336 B) 0.1664 C) 0.8472 D) Approximately 1

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51) In cluster sampling, a population is divided into subgroups called clusters, and a sample is randomly selected from each cluster. ⊚ true ⊚ false

52) The Office of Student Services at a large western state university maintains information on the study habits of its full-time students. Their studies indicate that the mean amount of time undergraduate students study per week is 20 hours. The hours studied follows the normal distribution with a population standard deviation of 6 hours. Suppose we select a random sample of 144 current students. What is the standard error of the mean?

A) 6.00 B) 2.00 C) 0.50 D) 0.25

53) The weight of trucks traveling on a particular section of I-475 has a population mean of 15.8 tons and a population standard deviation of 7.2 tons. What is the probability a state highway inspector could select a sample of 50 trucks and find the sample mean to be 14.3 tons or less?

A) 0.4278 B) 0.4292 C) 0.0708 D) 0.0722

54) If the size of a sample equals the size of the population, we would not expect any error in estimating the population parameter. ⊚ true ⊚ false

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55)

The mean of all possible sample means is equal to the population mean. ⊚ true ⊚ false

56) The Intelligence Quotient (IQ) test scores for adults are normally distributed with a population mean of 100 and a population standard deviation of 15. What is the probability we could select a sample of 60 adults and find the mean of this sample is less than 95?

A) 0.4951 B) 0.0049 C) 0.9902 D) 0.9628

57) A statewide sample survey is to be conducted. First, the state is subdivided into counties.

Seven counties are selected at random, and further sampling is concentrated on these seven counties. What type of sampling is this?

A) Simple random B) Cluster sampling C) Systematic random sampling D) Stratified sampling

58)

According to the central limit theorem, ______.

A) sample size is important when the population is not normally distributed B) the sampling distribution of the sample means is uniform C) the sampling distribution of the sample means will be skewed D) increasing the sample size decreases the dispersion of the sampling distribution

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59) If 40 samples of size 21 were selected from a population of 22,493, we would expect the mean of the sample means and the population mean to be close but not exactly equal. ⊚ true ⊚ false

60) An experiment involves selecting a random sample of 256 middle managers for study.

One item of interest is their annual incomes. The sample mean is computed to be $35,420.00. If the population standard deviation is $2,300.00, what is the standard error of the mean?

A) $143.75 B) $2,300.00 C) $8.98 D) $153.99

61) The central limit theorem states that for a sufficiently large sample, the sampling distribution of the means of all possible samples of size n generated from the population will be approximately normally distributed with the mean of the sampling distribution equal to σ2 and the variance equal to σ2/n. ⊚ true ⊚ false

62)

The mean of all the sample means is ______.

A) B) µ C) α D) σ

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63) A sampling distribution of the means is a probability distribution consisting of all possible sample means of a given sample size selected from a population. ⊚ true ⊚ false

64) When dividing a population into subgroups so that a random sample from each subgroup can be collected, what type of sampling is used?

A) Cluster sampling B) Systematic sampling C) Stratified random sampling D) Simple random sampling

65) The central limit theorem states that if the sample size, n, is sufficiently large, the sampling distribution of the means will be approximately normal, even when the population is skewed or uniform. ⊚ true ⊚ false

66) Manufacturers were subdivided into groups by volume of sales. Those with more than $100 million in sales were classified as large; those from $50 to $100 million as medium size; and those between $25 and $50 million, and so on. Samples were then selected from each of these groups. What is this type of sampling called?

A) Stratified random sampling B) Simple random sampling C) Systematic sampling D) Cluster sampling

67) As the size of the sample increases, what happens to the shape of thesampling distribution of sample means?

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A) It is positively skewed.

B) It is negatively skewed.

C) It cannot be predicted in advance.

D) It approaches a normal distribution.

68) In stratified random sampling, a population is divided into strata using naturally occurring geographic or other boundaries. Then, strata are randomly selected and a random sample is collected from each strata. ⊚ true ⊚ false

69) The Office of Student Services at a large western state university maintains information on the study habits of its full-time students. Their studies indicate that the mean amount of time undergraduate students study per week is 20 hours. The hours studied follows the normal distribution with a population standard deviation of six hours. Suppose we select a random sample of 100 current students. What is the probability that the mean of this sample is between 19 hours and 20 hours?

A) 0.0485 B) 0.4525 C) 0.0475 D) 0.4515

70)

What is the difference between a sample mean and the population mean called?

A) Interval estimate B) Sampling error C) Point estimate D) Standard error of the mean

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71)

The true sampling error is usually not known because ______.

A) The sample mean cannot be computed.

B) σ2 is unknown C) µ is unknown D) µ is a random variable

72) Sampling a population is often necessary because the cost of studying all the items in the population is prohibitive. ⊚ true ⊚ false

73) The BLS employer cost survey uses a sample to establish the average wage of receptionists. Based on a large number of observations, the distribution of receptionist wages is normally distributed with a mean $10.38/hour and a standard deviation of $2.05. What is the probability that the wages for a sample of 20 receptionists exceeds $11/hour?

A) 0.0222 B) 0.5498 C) 0.0881 D) 0.3000

74) When testing the safety of cars using crash tests, a sample of one or two cars is used because ______.

A) sampling is more accurate B) it is quicker C) cars are destroyed D) the population is very large

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75) The BLS employer cost survey uses a sample to establish the average wage of receptionists. Based on a large number of observations, the distribution of receptionist wages is normally distributed with a mean $10.38 and a standard deviation of $2.05. What is the probability that the wages for a sample of 20 receptionists are less than $8/hour?

A) 0.0000 B) 0.0881 C) 0.0222 D) 0.5498

76) The Intelligence Quotient (IQ) test scores for adults are normally distributed with a population mean of 100 and a population standard deviation of 15. What is the probability we could select a sample of 50 adults and find the mean of this sample is less than 95?

A) 0.4909 B) 0.0091 C) 0.9544 D) 0.9818

77) Bones Brothers & Associates prepare individual tax returns. Over prior years, Bones Brothers has maintained careful records regarding the time to prepare a return. The mean time to prepare a return is 90 minutes and the population standard deviation of this distribution is 14 minutes. Suppose 100 returns from this year are selected and analyzed regarding the preparation time. Which of the following assumptions do you need to make about the shape of the population distribution of all possible tax preparation times to make inferences about the mean time to complete a tax form?

A) The population distribution is skewed to the right.

B) The population distribution is skewed to the left.

C) The population distribution is normal.

D) The shape of the population distribution does not matter.

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78) The tread life of tires mounted on light-duty trucks follows the normal probability distribution with a population mean of 60,000 miles and a population standard deviation of 6,000 miles. Suppose we select a sample of 70 tires and use a simulator to determine the tread life.

What is the likelihood of finding that the sample mean is between 59,050 and 60,950?

A) 0.8132 B) 0.5934 C) 0.4066 D) 0.9066

79) The tread life of tires mounted on light-duty trucks follows the normal probability distribution with a population mean of 60,000 miles and a population standard deviation of 4,000 miles. Suppose we select a sample of 40 tires and use a simulator to determine the tread life.

What is the likelihood of finding that the sample mean is between 59,050 and 60,950?

A) 0.9332 B) 0.8664 C) 0.5668 D) 0.4332

80) Bones Brothers & Associates prepare individual tax returns. Over prior years, Bones Brothers has maintained careful records regarding the time to prepare a return. The mean time to prepare a return is 90 minutes, and the population standard deviation of this distribution is 14 minutes. Suppose 120 returns from this year are selected and analyzed regarding the preparation time. What is the probability that the mean time for the sample of 120 returns for this year is greater than 92?

A) 0.0662 B) 0.4338 C) 0.0594 D) Approximately 0

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81) The BLS uses sampling for its National Compensation Survey to report employment costs. In its first stage of sampling, it divides the U.S. into geographic regions. What type of sampling is this?

A) Random B) Cluster C) Systematic D) Stratified

82) In the sampling distribution of the sample means, the standard error of the mean will vary according to the size of the sample. As the sample size, n, gets larger, the variability of the sampling distribution of the means gets larger. ⊚ true ⊚ false

83)

Sampling error is the difference between a sample statistic and its corresponding ______.

A) sample mean B) trend C) population parameter D) variance

84)

The standard error of the mean is directly related to the sample size. ⊚ true ⊚ false

85) The weight of trucks traveling on a particular section of I-475 has a population mean of 15.8 tons and a population standard deviation of 4.2 tons. What is the probability a state highway inspector could select a sample of 49 trucks and find the sample mean to be 14.3 tons or less?

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A) 0.0062 B) 0.3632 C) 0.4938 D) 0.1368

86) It is often not feasible to study the entire population because it is impossible to observe all the items in the population. ⊚ true ⊚ false

87)

Convenience sampling A) is an unbiased sampling method.

B) collects sample information from groups that are easy to obtain.

C) is the same as simple random sampling.

D) ensures that samples are representative of the population.

88) The Office of Student Services at a large western state university maintains information on the study habits of its full-time students. Their studies indicate that the mean amount of time undergraduate students study per week is 20 hours. The hours studied follows the normal distribution with a population standard deviation of six hours. Suppose we select a random sample of 144 current students. What is the probability that the mean of this sample is between 19 hours and 20 hours?

A) 0.0228 B) 0.0675 C) 0.4325 D) 0.4772

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89)

When computing probabilities for the sampling distribution of the sample mean, the z-

statistic is computed as ⊚ true ⊚ false

90)

The mean of all possible sample means is equal to ______.

A) the population variance B) the population mean C) the sample variance D)

91) For a distribution of sample means constructed by sampling 6 items from a population of 12, ______.

A) the standard error will be 1 B) the sample size is 12 C) the mean of the sample means will be 2 D) there will be 924 possible sample means

92) <p>For a given population, the mean of all the sample means the mean of all (N) population observations (μ) are ______.

, of sample size n, and

A) <p>equal to B) equal to µ C) <p>equal to D) not equal

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Answer Key Test name: Chap 08_10e_Lind 1) C 2) B 3) B 4) C 5) C 6) TRUE 7) A 8) C 9) B 10) A 11) A 12) A 13) TRUE 14) D 15) A 16) C 17) A 18) B 19) D 20) FALSE 21) D 22) A 23) B 24) C 25) D 26) TRUE Version 1

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27) A 28) B 29) B 30) FALSE 31) TRUE 32) FALSE 33) D 34) TRUE 35) B 36) FALSE 37) D 38) B 39) D 40) D 41) C 42) TRUE 43) F 44) B 45) D 46) C 47) FALSE 48) D 49) A 50) C 51) FALSE 52) C 53) C 54) TRUE 55) TRUE 56) B Version 1

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57) B 58) A 59) TRUE 60) A 61) FALSE 62) B 63) TRUE 64) C 65) TRUE 66) A 67) D 68) FALSE 69) B 70) B 71) C 72) TRUE 73) C 74) C 75) A 76) B 77) D 78) A 79) B 80) C 81) B 82) FALSE 83) C 84) FALSE 85) A 86) TRUE Version 1

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87) B 88) D 89) FALSE 90) B 91) D 92) B

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CHAPTER 9 1) A random sample of 42 college graduates revealed that they worked an average of 5.5 years on the job before being promoted. The sample standard deviation was 1.1 years. Using the 0.99 degree of confidence, what is the confidence interval for the population mean?

A) 2.67 and 8.33 B) 4.40 and 6.60 C) 5.04 and 5.96 D) 5.06 and 5.94

2) University officials say that at least 70% of the voting student population supports a fee increase. If the 95% confidence interval estimating the proportion of students supporting the fee increase is [0.75, 0.85], what conclusion can be drawn?

A) Seventy percent is not in the interval, so another sample is needed.

B) Since this was not based on the population, no conclusion can be drawn.

C) The interval estimate is above 70%, so infer that it will be supported.

D) Seventy percent is not in the interval, so assume it will not be supported.

3) A survey of an urban university showed that 870 of 1,100 students sampled supported a fee increase to fund improvements to the student recreation center. Using the 99% level of confidence, what is the confidence interval for the proportion of students supporting the fee increase?

A) [0.751, 0.829] B) [0.767, 0.814] C) [0.759, 0.823] D) [0.771, 0.811]

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4) Roller bearings made by a lathe show a long-term process standard deviation of 0.064 inches. A weekly sample will be taken, and it is desired that the error in size be within +/− 0.01 inches. What sample size should be taken so that a 95% confidence interval is within +/− 0.01 inches?

A) 32 B) 158 C) 13 D) 543

5) If 95% and 98% confidence intervals were developed to estimate the true cost of an MP3 player with a known population standard deviation, what differences would they have?

A) The z-statistics would be different.

B) The point estimates of the population mean would be different.

C) The standard errors would be different.

D) The sample sizes would be different.

6) A confidence interval for a population proportion uses the uniform distribution to approximate the binomial distribution. ⊚ true ⊚ false

7)

A sample standard deviation is the best point estimate of the ___________.

A) population standard deviation B) population skewness C) population mode D) population range

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8) A bank wishes to estimate the mean credit card balance owed by its customers. The population standard deviation is estimated to be $300. If a 98% confidence interval is used and a margin of error of $81 is desired, how many customers should be sampled?

A) 75 B) 188 C) 533 D) 32

9) A local retail company wants to estimate the mean amount spent by customers. Their store's budget limits the number of surveys to 225. What is their maximum error of the estimated mean amount spent for a 99% level of confidence and an estimated standard deviation of $11.00?

A) $1.89 B) $2.00 C) 2% D) $11.00

10) Diameter measurements of 15 roller bearings made by a lathe for one week showed a mean of 1.824 inches and a sample standard deviation of 0.064 inches. What is the likelihood of the diameter is within +/− 0.03 inches?

A) 95% B) 99% C) 97% D) 90%

11)

When using Student's t to compute an interval estimate, ___________.

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A) we use the z-distribution B) we assume that the samples are collected from populations that are uniformly distributed C) we assume that the samples are collected from normally distributed populations D) we estimate the population mean based on the sample mean

12) A group of statistics students decided to conduct a survey at their university to find the average (mean) amount of time students spent studying per week. They sampled 240 students and found a mean of 22.3 hours per week. Assuming a population standard deviation of six hours, what is the 99% level of confidence?

A) [20.22, 22.0] B) [21.80, 22.80] C) [16.3, 28.3] D) [21.30, 23.30]

13) A survey of an urban university showed that 855 of 1,240 students sampled supported a fee increase to fund improvements to the student recreation center. Using the 95% level of confidence, what is the confidence interval for the proportion of students supporting the fee increase?

A) [0.613, 0.767] B) [0.670, 0.710] C) [0.664, 0.715] D) [0.658, 0.722]

14) A university surveyed recent graduates of the English department for their starting salaries. Four hundred graduates returned the survey. The average salary was $25,000, with a standard deviation of $2,500. What is the best point estimate of the population mean?

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A) $25,000 B) $400 C) $62.5 D) $2,500

15) A student wanted to construct a 95% confidence interval for the mean age of students in her statistics class. She randomly selected nine students. Their mean age was 19.1 years, with a sample standard deviation of 1.5 years. What is the 95% confidence interval for the population mean?

A) [15.64, 22.56] B) [17.42, 20.78] C) [17.95, 20.25] D) [18.03]

16)

A point estimate is a single value used to estimate a population parameter. ⊚ true ⊚ false

17) A survey of 50 retail stores revealed that the average price of a microwave was $375 with a sample standard deviation of $20. Assuming the population is normally distributed, what is the 99% confidence interval to estimate the true cost of the microwave?

A) $323.40 to $426.60 B) $367.42 to $382.58 C) $335.82 to $414.28 D) $315.00 to $415.00

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18) A population has a known standard deviation of 25. A simple random sample of 49 items is taken from the selected population. The sample mean (x-bar) is 300. What is the margin of error at the 95% confidence level?

A) ±49 B) ±0.714 C) ±7 D) ±93

19) Of the following characteristics, the t-distribution and z-distribution are the same in all but one. Which one is it?

A) Bell-shaped B) Continuous C) Mean = 0, and standard deviation = 1 D) Symmetrical

20) To determine the value of the standard error of the mean, the standard deviation is divided by the sample size. ⊚ true ⊚ false

21) A group of statistics students decided to conduct a survey at their university to find the average (mean) amount of time students spent studying per week. Assuming a population standard deviation of fourteen hours, what is the required sample size if the error should be less than one and a half hours with a 95% level of confidence?

A) 33 B) 305 C) 335 D) 186

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22) A total of 500 voters are randomly selected in a certain precinct and asked whether they plan to vote for the Democratic incumbent or the Republican challenger. Of the 500 surveyed, 350 said they would vote for the Democratic incumbent. Using the 0.99 level of confidence, what are the confidence limits for the proportion that plan to vote for the Democratic incumbent?

A) 0.612 and 0.712 B) 0.826 and 0.926 C) 0.397 and 0.797 D) 0.647 and 0.753

23) The mean weight of trucks traveling on a particular section of I-475 is not known. A state highway inspector needs an estimate of the population mean. He selects and weighs a random sample of 49 trucks and finds the mean weight is 15.8 tons. The population standard deviation is 3.8 tons. What is the 95% confidence interval for the population mean?

A) 16.1 and 18.1 B) 10.0 and 20.0 C) 13.2 and 17.6 D) 14.7 and 16.9

24) A survey of an urban university showed that 865 of 1,360 students sampled supported a fee increase to fund improvements to the student recreation center. Using the 99% level of confidence, what is the confidence interval for the proportion of students supporting the fee increase?

A) [0.596, 0.674] B) [0.616, 0.656] C) [0.602, 0.670] D) [0.612, 0.659]

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25) A survey of households in a small town showed that in 850 of 1,200 sampled households, at least one member attended a town meeting during the year. Using the 99% level of confidence, what is the confidence interval for the proportion of households represented at a town meeting?

A) [0.679, 0.680] B) [0.674, 0.742] C) [0.665, 0.694] D) [0.655, 0.705]

26) An interval estimate is a range of values in which the population parameter is likely to occur. ⊚ true ⊚ false

27) Mileage tests were conducted on a randomly selected sample of 100 newly developed automobile tires. The results showed that the mean tread life was 50,000 miles, with a standard deviation of 3,500 miles. What is the best estimate of the mean tread life in miles for the entire population of these tires?

A) 500 B) 35 C) 3,500 D) 50,000

28) A survey of 25 grocery stores revealed that the mean price of a gallon of milk was $2.98, with a standard error of $0.10. If 90% and 95% confidence intervals were developed to estimate the true cost of a gallon of milk, what similarities would they have?

A) Both use the same z-statistic.

B) Both have the same confidence level.

C) Both use the same t-statistic.

D) Both use the same point estimate of the population mean.

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29) A survey of an urban university showed that 870 of 1,100 students sampled supported a fee increase to fund improvements to the student recreation center. Using the 95% level of confidence, what is the confidence interval for the proportion of students supporting the fee increase?

A) [0.767, 0.815] B) [0.714, 0.866] C) [0.771, 0.811] D) [0.759, 0.822]

30) A research firm needs to estimate within 3% the proportion of junior executives leaving large manufacturing companies within three years. A 0.95 degree of confidence is to be used.

Several years ago, a study revealed that 29% of junior executives left their company within three years. To update this study, how many junior executives should be surveyed?

A) 764 B) 879 C) 782 D) 1,067

31) Diameter measurements of 15 roller bearings made by a lathe for one week showed a mean of 1.824 inches. The long-term process standard deviation is 0.064 inches. What is the 95% confidence interval of the mean diameter of all roller bearings?

A) 1.815 and 1.833 B) 1.521 and 2.838 C) 1.789 and 1.859 D) 1.792 and 1.856

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32) To determine the size of a sample, the standard deviation of the population must be estimated by either taking a pilot survey or by approximating it based on knowledge of the population. ⊚ true ⊚ false

33)

The distribution of Student's t has ___________.

A) a mean of zero and a standard deviation that depends on the sample size B) a mean of zero and a standard deviation of one C) a mean that depends on the sample size and a standard deviation of one D) a mean of one and a standard deviation of one

34) A bank wishes to estimate the mean credit card balance owed by its customers. The population standard deviation is estimated to be $300. If a 98% confidence interval is used and a margin of error of $75 is desired, how many customers should be sampled?

A) 629 B) 87 C) 44 D) 212

35) A university surveyed recent graduates of the English department for their starting salaries. One hundred and ninety six graduates returned the survey. The average salary was $28,800. The population standard deviation was $2,150. What is the 95% confidence interval for the mean salary of all graduates from the English department?

A) [$28,604; $28,996] B) [$26,650; $30,950] C) [$28,788; $28,812] D) [$28,499; $29,101]

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36) When we use a confidence interval to reach a conclusion about the population mean, we are applying a type of reasoning or logic called ___________.

A) statistical inference B) descriptive statistics C) graphics D) the normal distribution

37) A group of statistics students decided to conduct a survey at their university to estimate the average (mean) amount of time students spent studying per week. They sampled 554 students and found a mean of 22.3 hours per week. Assuming a population standard deviation of six hours, what is the 95% level of confidence?

A) [21.64, 22.96] B) [20.22, 22.0] C) [21.80, 22.80] D) [16.3, 28.3]

38) A research firm needs to estimate within 3% the proportion of junior executives leaving large manufacturing companies within three years. A 0.95 degree of confidence is to be used.

Several years ago, a study revealed that 21% of junior executives left their company within three years. To update this study, how many junior executives should be surveyed?

A) 612 B) 897 C) 709 D) 594

39) A random sample of 20 items is selected from a population. When computing a confidence interval for the population mean, what number of degrees of freedom should be used to determine the appropriate t-value?

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A) 25 B) 19 C) 21 D) 20

40) A total of 500 voters are randomly selected in a certain precinct and asked whether they plan to vote for the Democratic incumbent or the Republican challenger. Of the 500 surveyed, 275 said they would vote for the Democratic incumbent. Using the 0.99 level of confidence, what are the confidence limits for the proportion that plan to vote for the Democratic incumbent?

A) 0.493 and 0.607 B) 0.672 and 0.780 C) 0.458 and 0.566 D) 0.243 and 0.651

41) A local company wants to evaluate their quality of service by surveying their customers.

Their budget limits the number of surveys to 250. What is their maximum error of the estimated mean quality for a 95% level of confidence and an estimated standard deviation of 11?

A) 11% B) 2.72 C) 1.3404 D) 1.36

42) Suppose 1,600 of 2,000 registered voters sampled said they planned to vote for the Republican candidate for president. Using the 0.95 degree of confidence, what is the interval estimate for the population proportion (to the nearest 10th of a percent)?

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A) 78.2% to 81.8% B) 69.2% to 86.4% C) 76.5% to 83.5% D) 77.7% to 82.3%

43) A university surveyed recent graduates of the English department for their starting salaries. Four hundred graduates returned the survey. The average salary was $25,000. The population standard deviation was $2,500. What is the 95% confidence interval for the mean salary of all graduates from the English department?

A) [$24,755; $25,245] B) [$24,988; $25,012] C) [$22,500; $27,500] D) [$24,600; $25,600]

44) A z-statistic is used for a problem involving any sample size and an unknown population standard deviation. ⊚ true ⊚ false

45) When a confidence interval for a population mean is constructed from sample data, ___________.

A) we can conclude, for an infinite number of samples and corresponding confidence intervals, that the population mean is in a stated percentage of the intervals B) we cannot make any inferences C) we can conclude that the population mean is in the interval D) we can conclude that the population mean is not in the interval

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46) A local company wants to evaluate their quality of service by surveying their customers.

Their budget limits the number of surveys to 100. What is their maximum error of the estimated mean quality for a 95% level of confidence and an estimated standard deviation of 5?

A) 0.98 B) 5% C) 1.96 D) 0.9604

47)

The z-score or z-value corresponding to a 95.34% confidence interval is ___________.

A) 1.96 B) 1.99 C) 1.65 D) 1.68

48) Diameter measurements of 200 roller bearings made by a lathe for one week showed a mean of 1.824 inches and a sample standard deviation of 0.064 inches. What is the 95% confidence interval of the mean diameter of all roller bearings?

A) 1.789 and 1.859 B) 1.815 and 1.833 C) 1.792 and 1.856 D) 1.521 and 2.838

49) A university surveyed recent graduates of the English department for their starting salaries. Four hundred graduates returned the survey. The average salary was $25,000. The population standard deviation is $2,500. A 95% confidence interval is constructed. What does the confidence interval mean?

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A) The population mean is not in the interval.

B) There is a 5% chance that the computed interval does not contain the population mean.

C) The likelihood that any confidence interval based on a sample of 400 graduates will contain the population mean is 0.95.

D) The population mean is in the interval.

50)

A point estimate is a range of values used to estimate a population parameter. ⊚ true ⊚ false

51) A survey of 50 retail stores revealed that the average price of a microwave was $375, with a sample standard deviation of $20. Assuming the population is normally distributed, what is the 95% confidence interval to estimate the true cost of the microwave?

A) $369.31 to $380.69 B) $323.40 to $426.60 C) $328.40 to $421.60 D) $350.80 to $395.80

52)

The distribution of Student's t is ___________.

A) a discrete probability distribution B) negatively skewed C) positively skewed D) symmetrical

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53) A student wanted to construct a 99% confidence interval for the mean age of students in her statistics class. She randomly selected nine students. Their mean age was 19.1 years with a sample standard deviation of 1.5 years. What is the 99% confidence interval for the population mean?

A) [14.23, 23.98] B) [17.56, 20.64] C) [17.42, 20.78] D) [17.95, 20.25]

54) A group of marketing students at a large university wants to determine the proportion of first year students who use certain types of social media. The students want their estimate to be within 0.03 of the true proportion with a 90% level of confidence. How large of a sample is required if the population proportion is not known?

A) 752 B) Cannot be determined without more information C) 1,068 D) 347

55) A random sample of 42 college graduates revealed that they worked an average of 7.5 years on the job before being promoted. The sample standard deviation was 3.1 years. Using the 0.99 degree of confidence, what is the confidence interval for the population mean?

A) 6.21 and 8.79 B) 5.57 and 9.43 C) 3.25 and 12.58 D) 6.23 and 8.77

56) The mean weight of trucks traveling on a particular section of I-475 is not known. A state highway inspector needs an estimate of the population mean. He selects and weighs a random sample of 49 trucks and finds the mean weight is 17.1 tons. The population standard deviation is 5.1 tons. What is the 95% confidence interval for the population mean?

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A) 14.2 and 19.2 B) 17.1 and 19.7 C) 15.7 and 18.5 D) 11.0 and 21.6

57)

A sample mean is the best point estimate of ___________.

A) the population standard deviation B) the sample standard deviation C) the population mean D) the population median

58) A student wanted to construct a 95% confidence interval for the mean age of students in her statistics class. She randomly selected nine students. Their average age was 19.1 years with a sample standard deviation of 1.5 years. What is the best point estimate for the population mean?

A) 2.1 years B) 9 years C) 19.1 years D) 1.5 years

59)

How is the t-distribution similar to the standard z-distribution?

A) Both are discrete distributions.

B) Both are families of distributions.

C) Both are skewed distributions.

D) Both are continuous distributions.

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60) As the sample size for a t-distribution increases, the differences between the t-distribution and the standard normal distribution ___________.

A) become smaller, as the t-distribution approaches the standard normal distribution B) become greater C) are evident because the tails of the t-distribution become thicker D) are unchanged and remain the same

61) A survey of 50 retail stores revealed that the average price of a microwave was $375, with a sample standard deviation of $20. If 90% and 95% confidence intervals were developed to estimate the true cost of the microwave, what similarities would they have?

A) Both use the same t-statistic.

B) Both use the same point estimate of the population mean.

C) Both use the same z-statistic.

D) Both have the same confidence level.

62) A university surveyed recent graduates of the English department for their starting salaries. Five hundred and forty graduates returned the survey. The average salary was $26,400, with a standard deviation of $2,500. What is the best point estimate of the population mean?

A) $540 B) $26,400 C) $63.9 D) $2,500

63) One factor in determining the size of a sample is the degree of confidence selected. This is usually 0.95 or 0.99, but it may be any degree of confidence you specify. ⊚ true ⊚ false

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64) A survey of households in a small town showed that in 500 of 1,200 sampled households, at least one member attended a town meeting during the year. Using the 95% level of confidence, what is the confidence interval for the proportion of households represented at a town meeting?

A) [0.417, 0.427] B) [0.417, 0.445] C) [0.400, 0.417] D) [0.389, 0.445]

65) A sample of 2,000 union members was selected, and a survey recorded their opinions regarding a proposed management union contract. A total of 1,600 members were in favor of it.

A 95% confidence interval estimated that the population proportion was between 0.78 and 0.82.

This indicates that about 80 out of 100 similarly constructed intervals would include the population proportion. ⊚ true ⊚ false

66) The population variation has little or no effect in determining the size of a sample selected from the population. ⊚ true ⊚ false

67) A local retail company wants to estimate the mean amount spent by customers. Their store's budget limits the number of surveys to 225. What is their maximum error of the estimated mean amount spent for a 99% level of confidence and an estimated standard deviation of $10.00?

A) 1% B) $1.72 C) $10.00 D) $1.00

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68) Local government officials are interested in knowing if taxpayers are willing to support a school bond initiative that will require an increase in property taxes. A random sample of 750 likely voters was taken. Four hundred fifty of those sampled favored the school bond initiative.

The 95% confidence interval for the true proportion of voters favoring the initiative is ___________.

A) [0.400, 0.600] B) [0.500, 0.700] C) [0.565, 0.635] D) [0.541, 0.639]

69)

Which of the following is a point estimate for the population mean (µ)?

A) x/n B) σ C) D) s

70) A survey of 25 grocery stores revealed that the mean price of a gallon of milk was $2.98, with a standard error of $0.10. What is the 95% confidence interval to estimate the true cost of a gallon of milk?

A) $2.81 to $3.15 B) $2.77 to $3.19 C) $2.94 to $3.02 D) $2.95 to $3.01

71) Which of the following is not necessary to determine how large a sample to select from a population?

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A) The size of the population B) The level of confidence in estimating the population parameter C) The maximum allowable error in estimating the population parameter D) An estimate of the population variation

72) When using the t-distribution to calculate a confidence interval, we assume that the population of interest is normal or nearly normal. ⊚ true ⊚ false

73)

A confidence interval for a population mean ___________.

A) estimates the population range B) estimates likelihood or probability C) estimates a likely interval for a population mean D) estimates the population standard deviation

74) A survey of 25 grocery stores revealed that the average price of a gallon of milk was $2.98, with a standard error of $0.10. What is the 98% confidence interval to estimate the true cost of a gallon of milk?

A) $2.73 to $3.23 B) $2.85 to $3.11 C) $2.94 to $3.02 D) $2.95 to $3.01

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75) The mean number of travel days per year for salespeople employed by three hardware distributors needs to be estimated with a 0.95 degree of confidence. For a small pilot study, the mean was 150 days and the standard deviation was 16 days. If the population mean is estimated within two days, how many salespeople should be sampled?

A) 961 B) 904 C) 246 D) 3,908

76) A group of statistics students decided to conduct a survey at their university to find the average (mean) amount of time students spent studying per week. Assuming a population standard deviation of three hours, what is the required sample size if the error should be less than a half hour with a 99% level of confidence?

A) 15 B) 554 C) 196 D) 239

77) The mean number of travel days per year for salespeople employed by three hardware distributors needs to be estimated with a 0.90 degree of confidence. For a small pilot study, the mean was 150 days and the standard deviation was 14 days. If the population mean is estimated within two days, how many salespeople should be sampled?

A) 452 B) 2,100 C) 511 D) 133

78) Knowing the population standard deviation, a 95% confidence interval infers that the population mean ___________.

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A) is too large B) is within ±1.96 standard deviations of the sample mean C) is between 0 and 100% D) is within ±1.96 standard errors of the sample mean

79) The 95% confidence interval states that 95% of the sample means of a specified sample size selected from a population will lie within plus and minus 1.96 standard deviations of the hypothesized population mean. ⊚ true ⊚ false

80) A group of statistics students decided to conduct a survey at their university to find the average (mean) amount of time students spent studying per week. Assuming a population standard deviation of six hours, what is the required sample size if the error should be less than a half hour with a 95% level of confidence?

A) 393 B) 239 C) 35 D) 554

81) A research firm wants to compute an interval estimate with 90% confidence for the mean time to complete an employment test. Assuming a population standard deviation of three hours, what is the required sample size if the error should be less than a half hour?

A) 16 B) 10 C) 196 D) 98

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82) Suppose 1,872 of 2,600 registered voters sampled said they planned to vote for the Republican candidate for president. Using the 0.95 degree of confidence, what is the interval estimate for the population proportion (to the nearest 10th of a percent)?

A) 61.3% to 78.3% B) 68.6% to 75.4% C) 70.3% to 73.7% D) 69.8% to 74.2%

83)

Which statement(s) is(are) correct about the t-distribution?

A) All of these are correct.

B) Its shape is symmetric.

C) The mean is zero.

D) Its dispersion is based on degrees of freedom.

84)

What is the interpretation of a 96% confidence level?

A) There's a 96% chance that the given interval includes the true value of the population parameter.

B) The interval contains 96% of all sample means.

C) There's a 4% chance that the given interval does not include the true value of the population parameter.

D) Approximately 96 out of 100 such intervals would include the true value of the population parameter.

85) Local government officials are interested in knowing if taxpayers are willing to support a school bond initiative that will require an increase in property taxes. A random sample of 750 likely voters was taken. Four hundred of those sampled favored the school bond initiative. The 98% confidence interval for the true proportion of voters favoring the initiative is ___________.

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A) [0.565, 0.635] B) [0.541, 0.639] C) [0.500, 0.700] D) [0.491, 0.575]

86) A group of marketing students at a large university wants to determine the proportion of first year students who use certain types of social media. The students want their estimate to be within 0.03 of the true proportion with a 95% level of confidence. Two years ago, a similar study determined the proportion to be 0.796. How large of a sample is required?

A) 752 B) 694 C) 489 D) Cannot be determined without more information

87)

An interval estimate is a single value used to estimate a population parameter. ⊚ true ⊚ false

88) Diameter measurements of 15 roller bearings made by a lathe for one week showed a mean of 1.824 inches and a sample standard deviation of 0.064 inches. What is the 95% confidence interval of the mean diameter of all roller bearings?

A) 1.521 and 2.838 B) 1.815 and 1.833 C) 1.792 and 1.856 D) 1.789 and 1.859

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89) A random sample of 85 supervisors revealed that they worked an average of 8.3 years before being promoted. The population standard deviation was 3.5 years. Using the 0.95level of confidence, what is the confidence interval for the population mean?

A) 5.57 and 9.33 B) 8.41 and 10.17 C) 7.91 and 9.67 D) 7.56 and 9.04

90)

What kind of distribution is the t-distribution?

A) Subjective B) A z-distribution C) Continuous D) Discrete

91) A random sample of 85 supervisors revealed that they worked an average of 6.5 years before being promoted. The population standard deviation was 1.7 years. Using the 0.95level of confidence, what is the confidence interval for the population mean?

A) 4.15 and 7.15 B) 6.14 and 6.86 C) 6.99 and 7.99 D) 6.49 and 7.49

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Answer Key Test name: Chap 09_10e_Lind 1) C 2) C 3) C 4) B 5) A 6) FALSE 7) A 8) A 9) A 10) D 11) C 12) D 13) C 14) A 15) C 16) TRUE 17) B 18) C 19) C 20) FALSE 21) C 22) D 23) D 24) C 25) B 26) TRUE Version 1

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27) D 28) D 29) A 30) B 31) D 32) TRUE 33) A 34) B 35) D 36) A 37) C 38) C 39) B 40) A 41) D 42) A 43) A 44) FALSE 45) A 46) A 47) B 48) B 49) C 50) FALSE 51) A 52) D 53) C 54) A 55) A 56) C Version 1

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57) C 58) C 59) D 60) A 61) B 62) B 63) TRUE 64) D 65) FALSE 66) FALSE 67) B 68) C 69) C 70) B 71) A 72) TRUE 73) C 74) A 75) C 76) D 77) D 78) D 79) TRUE 80) D 81) D 82) C 83) A 84) D 85) D 86) B Version 1

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87) FALSE 88) D 89) D 90) C 91) B

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CHAPTER 10 1) The mean annual incomes of certified welders are normally distributed with a mean of $50,000 and a population standard deviation of $2,000. The ship building association wishes to find out whether their welders earn more or less than $50,000 annually. The alternate hypothesis is that the mean is not $50,000. If the level of significance is 0.10, what is the critical value?

A) ±1.282 B) ±1.645 C) −1.282 D) +1.645

2) Assuming that the null hypothesis is true, a p-value is the probability of observing a sample value as extreme as, or more extreme than, the observed sample observation. ⊚ true ⊚ false

3) The average cost of tuition plus room and board for a small private liberal arts college is reported to be $8,500 per term, but a financial administrator believes that the average cost is higher. A study conducted using 350 small liberal arts colleges showed that the average cost per term is $8,745. The population standard deviation is $1,200. Let α = 0.05. Based on the computed test statistic or p-value, what is our decision about the average cost?

A) Not equal to $8,500 B) Less than $8,500 C) Equal to $8,500 D) Greater than $8,500

4) For a two-tailed test with a 0.05 significance level, where is the rejection region when n is large and the population standard deviation is known?

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A) Greater than +1.960 and less than −1.960 B) Between ±1.960 C) Greater than +1.645 and less than −1.645 D) Between ±1.645

5)

If we reject the null hypothesis, what can we conclude subject to the probability, α?

A) The null hypothesis is true.

B) Both the null hypothesis and the alternative hypothesis are true.

C) The alternative hypothesis is false.

D) Reject the null with a probability, α, of making a Type I error.

6) Consider a two-tailed test with a level of confidence of 99%. The p-value is determined to be 0.05; therefore, the null hypothesis ___________.

A) must be rejected B) may or may not be rejected depending on the square root of the sample size C) is the same as the alternative hypothesis D) should not be rejected

7) Hypothesis testing is a procedure that uses sample evidence and probability theory to decide whether to reject or fail to reject a hypothesis. ⊚ true ⊚ false

8) Consider a left-tailed test, where the p-value is found to be 0.10. If the sample size n for this test is 52, then the t-statistic will have a value of _______.

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A) −1.676 B) −1.298 C) +1.298 D) +1.676

9) The average cost of tuition plus room and board for a small private liberal arts college is reported to be $9,200 per term, but a financial administrator believes that the average cost is higher. A study conducted using 350 small liberal arts colleges showed that the average cost per term is $9,515. The population standard deviation is $1,200. Let α = 0.05. What is the p-value for this test?

A) 0.6029 B) 0.0500 C) 1.2150 D) 0

10)

Consider a two-tailed test with a level of confidence of 82.10%. The z-value is _______.

A) 2.68 B) 0.90 C) 2.01 D) 1.34

11) A hypothesis regarding the weight of newborn infants at a community hospital is that the mean is 8.1 pounds. A sample of seven infants is randomly selected and their weights at birth are recorded as 7.1, 10.1, 10.1, 11.1, 8.1, 12.1, and 13.1 pounds. If α = 0.100, what is the critical value? The population standard deviation is unknown.

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A) ±1.861 B) ±1.943 C) ±1.439 D) 0

12) A hypothesis regarding the weight of newborn infants at a community hospital is that the mean is 6.6 pounds. A sample of seven infants is randomly selected and their weights at birth are recorded as 9.0, 7.3, 6.0, 8.8, 6.8, 8.4, and 6.6 pounds. What is the sample standard deviation?

A) 1.177 B) 1.090 C) 1.188 D) 1.386

13) If the null hypothesis is false and the researchers do not reject it, a Type I error has been made. ⊚ true ⊚ false

14) The researcher must decide on the level of significance before formulating a decision rule and collecting sample data. ⊚ true ⊚ false

15)

Which of the following is NOT one of the six steps in the hypothesis testing procedure?

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A) Select a level forβ.

B) Formulate a decision rule.

C) Identify the test statistic.

D) State the null and alternate hypotheses.

16) For a one-tailed hypothesis test, the critical z-value of the test statistic is −2.33. Which of the following is true about the hypothesis test?

A) α = 0.05 for an upper-tailed test B) α = 0.01 for an upper-tailed test C) α = 0.01 for a lower-tailed test D) α = 0.05 for a lower-tailed test

17)

In hypothesis testing, what is the level of significance?

A) The risk of rejecting the null hypothesis when it is true.

B) All of these answers apply.

C) It is selected before a decision rule can be formulated.

D) A value between 0 and 1.

E) A value symbolized by the Greek letter α.

18) A machine is set to fill the small-size packages of M&M candies with 75 candies per bag.

A sample revealed one bags of 73, four bags of 79, three bag of 80, and three bags of 80. To test the hypothesis that the mean candies per bag is 77, how many degrees of freedom are there?

A) 10 B) 12 C) 6 D) 11

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19) A hypothesis regarding the weight of newborn infants at a community hospital is that the mean is 6.6 pounds. A sample of seven infants is randomly selected and their weights at birth are recorded as 9.0, 7.3, 6.0, 8.8, 6.8, 8.4, and 6.6 pounds. What are the degrees of freedom?

A) 6.6 B) 6 C) 8 D) 7

20) For a one-tailed test with a 0.05 level of significance, the critical z-statistic is 1.645, but the critical t-statistic is 1.96. ⊚ true ⊚ false

21) Consider a two-tailed test with a level of confidence of 80.30%. The z-value is ___________.

A) 1.96 B) 1.29 C) 0.85 D) 2.58

22) A hypothesis regarding the weight of newborn infants at a community hospital is that the mean is 6.6 pounds. A sample of seven infants is randomly selected and their weights at birth are recorded as 9.0, 7.3, 6.0, 8.8, 6.8, 8.4, and 6.6 pounds. The null hypothesis is ___________.

A) H0: µ ≥ 6.6 B) H0: µ ≤ 7.6 C) H0: µ = 6.6 D) H0: µ > 7.6

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23)

A null hypothesis makes a claim about a ___________.

A) sample mean B) sample statistic C) population parameter D) Type II error

24)

Define the level of significance.

A) It is the beta error.

B) It is a z-value of 1.96.

C) It is the probability of a Type II error.

D) It is the probability of a Type I error.

25) Sales at a fast-food restaurant average $6,300 per day. The restaurant decided to introduce an advertising campaign to increase daily sales. To determine the effectiveness of the advertising campaign, a sample of 64 days of sales were taken. They found that the average daily sales were $6,520 per day. From past history, the restaurant knew that its population standard deviation is about $1,000. The value of the test statistic is _______.

A) 1.76 B) 6.30 C) 1.99 D) 6.52

26) The average cost of tuition plus room and board for a small private liberal arts college is reported to be $8,500 per term, but a financial administrator believes that the average cost is higher. A study conducted using 350 small liberal arts colleges showed that the average cost per term is $8,745. The population standard deviation is $1,200. Let α = 0.05. What is the critical zvalue for this test?

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A) −1.645 B) −1.960 C) +1.645 D) +1.960

27) The average cost of tuition plus room and board at for a small private liberal arts college is reported to be $8,500 per term, but a financial administrator believes that the average cost is higher. A study conducted using 350 small liberal arts colleges showed that the average cost per term is $8,745. The population standard deviation is $1,200. Let α = 0.05. What is the test statistic for this test?

A) +3.82 B) ±3.82 C) −3.82 D) +0.204

28) A machine is set to fill the small-size packages of M&M candies with 56 candies per bag.

A sample revealed three bags of 56, two bags of 57, one bag of 55, and two bags of 58. To test the hypothesis that the mean candies per bag is 56, how many degrees of freedom are there?

A) 7 B) 8 C) 9 D) 1

29) The mean annual incomes of certified welders are normally distributed with the mean of $50,000 and a population standard deviation of $2,000. The ship building association wishes to find out whether their welders earn more or less than $50,000 annually. The alternate hypothesis is that the mean is not $50,000. Which of the following is the alternate hypothesis?

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A) H1: ≠ $50,000 B) H1: µ ≠ $50,000 C) H1: µ = $50,000 D) H1: µ < $50,000

30) A hypothesis regarding the weight of newborn infants at a community hospital is that the mean is 18.1 pounds. A sample of seven infants is randomly selected and their weights at birth are recorded as 17.1, 20.1, 21.1, 22.1, 19.1, 26.1, and 26.1 pounds. What is the sample standard deviation?

A) 11.619 B) 3.322 C) 3.322 D) 3.409 E) 3.420

31) A manufacturer wants to increase the shelf life of a line of cake mixes. Past records indicate that the average shelf life of the mix is 216 days. After a revised mix has been developed, a sample of nine boxes of cake mix gave these shelf lives (in days): 215, 217, 218, 219, 216, 217, 217, 218, and 218. Using α = 0.025, has the shelf life of the cake mix increased?

A) No, because the computed p-value is less than 0.025.

B) No, because 217.22 is quite close to 216.

C) Yes, because the computed p-value is less than 0.025.

D) Yes, because the computed p-value is greater than 0.025.

32) Consider a left-tailed test, where the p-value is found to be 0.10. If the sample size n for this test is 49, then the t-statistic will have a value of ___________.

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A) +1.677 B) +1.299 C) −1.299 D) −1.677

33) The level of significance is the probability of rejecting the null hypothesis when it is actually true. ⊚ true ⊚ false

34)

A p-value is the same as a stated significance level. ⊚ true ⊚ false

35)

What is another name for the alternate hypothesis?

A) Research hypothesis B) Null hypothesis C) Hypothesis of no difference D) Rejected hypothesis

36) A random sample of size 15 is selected from a normal population. The population standard deviation is unknown. Assume the null hypothesis indicates a two-tailed test and the researcher decided to use the 0.10 significance level. For what values of p-value will the null hypothesis NOT be rejected?

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A) To the left of −1.645 or to the right of 1.645 B) Greater than 0.10.

C) To the left of −1.345 or to the right of 1.345 D) Less than or equal to 0.10.

37) What are the critical values for a two-tailed test with a 0.01 level of significance when n is large and the population standard deviation is known?

A) Above 2.576 and below −2.576 B) Above 1.000 and below −1.000 C) Above 1.960 and below −1.960 D) Above 1.645 and below −1.645

38) Sales at a fast-food restaurant average $6,000 per day. The restaurant decided to introduce an advertising campaign to increase daily sales. To determine the effectiveness of the advertising campaign, a sample of 49 days of sales were taken. They found that the average daily sales were $6,300 per day. From past history, the restaurant knew that its population standard deviation is about $1,000. The restaurant wishes to test whether sales have increased as a result of the advertising campaign. If the level of significance is 0.05, what is the decision?

A) Fail to reject the null hypothesis.

B) Reject the null hypothesis and conclude that the mean is equal to $6,000 per day.

C) Reject the null hypothesis and conclude the mean is higher than $6,000 per day.

D) Reject the null hypothesis and conclude the mean is lower than $6,000 per day.

39)

The probability of a Type II error is represented by ___________.

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A) α B) the Type I error C) σ D) β

40) To conduct a test of hypothesis with a small sample, we make an assumption that ___________.

A) the region of acceptance will be wider than for large samples B) a larger computed value of t will be needed to reject the null hypothesis C) the confidence interval will be wider than for large samples D) the population is normally distributed

41) A hypothesis regarding the weight of newborn infants at a community hospital is that the mean is 18.1 pounds. A sample of seven infants is randomly selected and their weights at birth are recorded as 17.1, 20.1, 21.1, 22.1, 19.1, 26.1, and 26.1 pounds. What are the degrees of freedom?

A) 7 B) 25.7 C) 6 D) 18.1

42) For an alternative hypothesis: µ > 6,700, where is the rejection region for the hypothesis test located?

A) In both tails B) In the center C) In the right or upper tail D) In the left or lower tail

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43) Sales at a fast-food restaurant average $6,000 per day. The restaurant decided to introduce an advertising campaign to increase daily sales. To determine the effectiveness of the advertising campaign, a sample of 49 days of sales were taken. They found that the average daily sales were $6,300 per day. From past history, the restaurant knew that its population standard deviation is about $1,000. If the level of significance is 0.01, have sales increased as a result of the advertising campaign?

A) Reject the null hypothesis and conclude the mean is lower than $6,000 per day.

B) Reject the null hypothesis and conclude that the mean is equal to $6,000 per day.

C) Fail to reject the null hypothesis.

D) Reject the null hypothesis and conclude the mean is higher than $6,000 per day.

44) The mean annual income of certified welders is normally distributed with a mean of $50,000 and a population standard deviation of $2,000. The ship building association wishes to find out whether their welders earn more or less than $50,000 annually. The alternate hypothesis is that the mean is not $50,000. If the level of significance is 0.10, what is the decision rule?

A) Reject the null hypothesis if the computed p-value is above 0.20.

B) Reject the null hypothesis if the computed p-value is above 0.10.

C) Do not reject the null hypothesis if the computed p-value is below 0.10.

D) Do not reject the null hypothesis if the computed p-value is above 0.10.

45) If the alternate hypothesis states that µ ≠ 4,000, where is the rejection region for the hypothesis test?

A) In the upper or right tail B) In both tails C) In the lower or left tail D) In the center

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46) The mean length of a candy bar is 43 millimeters. There is concern that the settings of the machine cutting the bars have changed. Test the claim at the 0.02 level of significance that there has been no change in the mean length. The alternate hypothesis is that there has been a change.

Twelve bars (n = 12) were selected at random and their lengths in millimeters recorded. The lengths (in millimeters) are 42, 39, 42, 45, 43, 40, 39, 41, 40, 42, 43, and 42. The mean of the sample is 41.5 and the standard deviation is 1.784. If the computed t = −2.913, has there been a statistically significant change in the mean length of the bars?

A) Yes, because the computed t lies in the rejection region.

B) No, because the information given is not complete.

C) Yes, because 43 is greater than 41.5.

D) No, because the computed t lies in the area to the right of −2.718.

47) A manufacturer wants to increase the shelf life of a line of cake mixes. Past records indicate that the average shelf life of the mix is 230 days. After a revised mix was developed, a sample of nine boxes of cake mix gave these shelf lives (in days): 229,232, 233, 235, 232, 239, 239, 240, and 236. Using α = 0.025, has the shelf life of the cake mix increased?

A) No, because 235.00 is quite close to 230.

B) Yes, because computed t is greater than the critical value.

C) Yes, because computed t is less than the critical value.

D) No, because computed t lies in the region of acceptance.

48) The mean annual incomes of certified welders are normally distributed with a mean of $50,000 and a population standard deviation of $2,000. The ship building association wishes to find out whether their welders earn more or less than $50,000 annually. A sample of 100 welders is taken and the mean annual income of the sample is $50,350. If the level of significance is 0.05, what conclusion should be drawn?

A) Reject the null hypothesis as the test statistic is greater than the critical value of t.

B) Do not reject the null hypothesis as the test statistic is less than the critical value of t.

C) Reject the null hypothesis as the test statistic is greater than the critical value of z.

D) Do not reject the null hypothesis as the test statistic is less than the critical value of z.

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49) A hypothesis regarding the weight of newborn infants at a community hospital is that the mean is 6.6 pounds. A sample of seven infants is randomly selected and their weights at birth are recorded as 9.0, 7.3, 6.0, 8.8, 6.8, 8.4, and 6.6 pounds. What is the decision for a statistically significant change in average weights at birth at the 5% level of significance?

A) Reject the null hypothesis and conclude the mean is lower than 6.6 pounds.

B) Reject the null hypothesis and conclude the mean is higher than 6.6 pounds.

C) Fail to reject the null hypothesis.

D) Cannot calculate because the population standard deviation is unknown.

50)

What is the probability of making a Type II error if the null hypothesis is actually true?

A) 0 B) 0.05 C) α D) 1

51) The mean weight of newborn infants at a community hospital is 6.6 pounds. A sample of seven infants is randomly selected and their weights at birth are recorded as 9.0, 7.3, 6.0, 8.8, 6.8, 8.4, and 6.6 pounds. Does the sample data show a significant increase in the average birthrate at a 5% level of significance?

A) Cannot calculate because the population standard deviation is unknown.

B) Fail to reject the null hypothesis and conclude the mean is 6.6 pounds.

C) Reject the null hypothesis and conclude the mean is greater than 6.6 pounds.

D) Reject the null hypothesis and conclude the mean is lower than 6.6 pounds.

52) A hypothesis regarding the weight of newborn infants at a community hospital is that the mean is 7.1 pounds. A sample of seven infants is randomly selected and their weights at birth are recorded as 6.1, 8.1, 9.1, 10.1, 7.1, 11.1, and 12.1 pounds. What is the sample mean?

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A) 3.990 B) 7.1 C) 9.1 D) 2.220

53)

A Type II error is the probability of rejecting the null hypothesis when it is actually true. ⊚ true ⊚ false

54)

The probability of a Type II error is represented by the Greek symbol β. ⊚ true ⊚ false

55) A hypothesis regarding the weight of newborn infants at a community hospital is that the mean is 8.1 pounds. A sample of seven infants is randomly selected and their weights at birth are recorded as 7.1, 10.1, 10.1, 11.1, 8.1, 12.1, and 13.1 pounds. What is the sample variance?

A) 8.1 B) 10.2 C) 4.476 D) 4.267

56) The mean length of a candy bar is 43 millimeters. There is concern that the settings of the machine cutting the bars have changed. Test the claim at the 0.02 level of significance that there has been no change in the mean length. The alternate hypothesis is that there has been a change.

Twelve bars (n = 12) were selected at random and their lengths in millimeters recorded. The lengths (in millimeters) are 42, 39, 42, 45, 43, 40, 39, 41, 40, 42, 43, and 42. Has there been a statistically significant change in the mean length of the bars?

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A) No, because the information given is not complete.

B) No, because the computed p-value is greater than 0.02.

C) Yes, because 43 is greater than 41.5.

D) Yes, because the computed p-value lies in the rejection region.

57) A test statistic is a value computed from sample information that is used to test the null hypothesis. ⊚ true ⊚ false

58) If the critical z-value for a hypothesis test equals 2.45, what value of the test statistic would provide the least chance of making a Type I error?

A) 4.56 B) 3.74 C) 1.07 D) 2.46

59) A random sample of size 15 is selected from a normal population. The population standard deviation is unknown. Assume the null hypothesis indicates a two-tailed test and the researcher decided to use the 0.10 significance level. For what values of t will the null hypothesis not be rejected?

A) Between −1.282 and 1.282 B) Between −1.761 and 1.761 C) To the left of −1.645 or to the right of 1.645 D) To the left of −1.345 or to the right of 1.345

60)

What is a Type II error?

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A) Rejecting a false null hypothesis B) Rejecting a false alternate hypothesis C) Accepting a false alternate hypothesis D) Failing to reject a false null hypothesis

61)

The Greek letter used to represent the probability of a Type I error is alpha (α). ⊚ true ⊚ false

62) Sales at a fast-food restaurant average $6,000 per day. The restaurant decided to introduce an advertising campaign to increase daily sales. To determine the effectiveness of the advertising campaign, a sample of 49 days of sales were taken. They found that the average daily sales were $6,300 per day. From past history, the restaurant knew that its population standard deviation is about $1,000. If the level of significance is 0.025, have sales increased as a result of the advertising campaign?

A) Fail to reject the null hypothesis.

B) Reject the null hypothesis and conclude the mean is higher than $6,000 per day.

C) Reject the null hypothesis and conclude the mean is lower than $6,000 per day.

D) Reject the null hypothesis and conclude that the mean is equal to $6,000 per day.

63)

If the null hypothesis is µ ≥ 200, then a two-tail test is being conducted. ⊚ true ⊚ false

64) The mean annual incomes of certified welders are normally distributed with a mean of $51,550 and a population standard deviation of $2,000. The ship building association wishes to find out whether their welders earn more or less than $51,550 annually. A sample of 100 welders is taken and the mean annual income of the sample is $51,900. If the level of significance is 0.05, what conclusion should be drawn?

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A) Do not reject the null hypothesis as the test statistic is less than the critical value of z.

B) Reject the null hypothesis as the test statistic is greater than the critical value of z.

C) Reject the null hypothesis as the test statistic is greater than the critical value of t.

D) Do not reject the null hypothesis as the test statistic is less than the critical value of t.

65) A consumer products company wants to increase the absorption capacity of a sponge.

Based on past data, the average sponge could absorb 3.5 ounces. After the redesign, the absorption amounts of a sample of sponges were (in ounces): 4.1, 3.7, 3.3, 3.5, 3.8, 3.9, 3.6, 3.8, 4.0, and 3.9. At the 0.01 level of significance, what is the decision rule to test if the new design increased the absorption of the sponge?

A) Reject the null hypothesis; the computed p-value is less than 1%.

B) Do not reject the null hypothesis; the computed p-value is less than 1%.

C) Do not reject the null hypothesis; the computed p-value is greater than 1%.

D) Reject the null hypothesis; the computed p-value is greater than 1%.

66) Consider a right-tailed test (upper tail) and a sample size of 40 at the 95% confidence level. The value of t is ___________.

A) −2.023 B) +2.023 C) −1.685 D) +1.685

67) A hypothesis regarding the weight of newborn infants at a community hospital is that the mean is 6.6 pounds. A sample of seven infants is randomly selected and their weights at birth are recorded as 9.0, 7.3, 6.0, 8.8, 6.8, 8.4, and 6.6 pounds. What is the sample mean?

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A) 7.6 B) 2.447 C) 6.6 D) 1.177

68) A hypothesis regarding the weight of newborn infants at a community hospital is that the mean is 6.6 pounds. A sample of seven infants is randomly selected and their weights at birth are recorded as 9.0, 7.3, 6.0, 8.8, 6.8, 8.4, and 6.6 pounds. What is the sample variance?

A) 1.177 B) 1.386 C) 6.6 D) 7.6

69) The mean annual income of certified welders is normally distributed with a mean of $50,000 and a population standard deviation of $2,000. The ship building association wishes to find out whether their welders earn more or less than $50,000 annually. The alternate hypothesis is that the mean is not $50,000. If the level of significance is 0.10, what is the decision rule?

A) Do not reject the null hypothesis if computed z lies between −1.645 and +1.645; otherwise, reject it.

B) Do not reject the null hypothesis if computed z is greater than 1.645; otherwise, reject it.

C) Reject the null hypothesis if computed z is below −1.960; otherwise, reject it.

D) Do not reject the null hypothesis if computed z lies between −1.960 and +1.960; otherwise, reject it.

70)

What are the critical z-values for a two-tailed hypothesis test if α = 0.01?

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A) ±2.326 B) ±1.645 C) ±2.576 D) ±1.960

71) An alternate hypothesis is a statement about a population parameter that is accepted when the null hypothesis is rejected. ⊚ true ⊚ false

72) The average cost of tuition plus room and board for a small private liberal arts college is reported to be $8,600 per term, but a financial administrator believes that the average cost is higher. A study conducted using 350 small liberal arts colleges showed that the average cost per term is $8,855. The population standard deviation is $1,200. Let α = 0.05. What is the test statistic for this test?

A) +3.98 B) ±3.98 C) −3.98 D) +0.360

73) Using a 5% level of significance and a sample size of 25, what is the critical t-value for a null hypothesis, H0: µ ≤ 100?

A) 2.064 B) 2.060 C) 1.708 D) 1.711

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74) The mean annual incomes of certified welders are normally distributed with a mean of $50,000 and a population standard deviation of $2,000. The ship building association wishes to find out whether their welders earn more or less than $50,000 annually. A sample of 100 welders is taken and the mean annual income of the sample is $50,350. If the level of significance is 0.10, what conclusion should be drawn?

A) Reject the null hypothesis as the test statistic is greater than the critical value of z.

B) Reject the null hypothesis as the test statistic is greater than the critical value of t.

C) Do not reject the null hypothesis as the test statistic is less than the critical value of t.

D) Do not reject the null hypothesis as the test statistic is less than the critical value of z.

75) For a null hypothesis, H0: µ = 4,000, if the 1% level of significance is used and the pvalue is 0.5%, what is our decision regarding the null hypothesis?

A) Do not reject H0.

B) Reject H0.

C) None of these answers apply.

D) Reject H1.

76) The mean annual incomes of certified welders are normally distributed with a mean of $50,000 and a population standard deviation of $2,000. The ship building association wishes to find out whether their welders earn more or less than $50,000 annually. A sample of 100 welders is taken and the mean annual income of the sample is $50,350. If the level of significance is 0.05, what conclusion should be drawn?

A) Do not reject the null hypothesis as the p-value is less than the level of significance.

B) Reject the null hypothesis as the p-value is greater than the level of significance.

C) Reject the null hypothesis as the p-value is less than the level of significance.

D) Do not reject the null hypothesis as the p-value is greater than the level of significance.

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77) For a null hypothesis, H0: µ = 4,000, if the 1% level of significance is used and the z-test statistic is +6.00, what is our decision regarding the null hypothesis?

A) None of these answers apply.

B) Do not reject H0.

C) Reject H1.

D) Reject H0.

78) Which symbol represents a test statistic used to test a hypothesis about a population mean?

A) β B) z C) α D) μ

79) The average cost of tuition and room and board for a small private liberal arts college is reported to be $8,500 per term, but a financial administrator believes that the average cost is higher. A study conducted using 350 small liberal arts colleges showed that the average cost per term is $8,745. The population standard deviation is $1,200. Let α = 0.05. What are the null and alternative hypotheses for this study?

A) H0: µ ≥ $9,000; H1: µ < $9,000 B) H0: µ ≥ $8,500; H1: µ < $8,500 C) H0: µ ≤ $9,000; H1: µ > $9,000 D) H0: µ ≤ $8,500; H1: µ > $8,500

80) A manufacturer wants to increase the shelf life of a line of cake mixes. Past records indicate that the average shelf life of the mix is 216 days. After a revised mix was developed, a sample of nine boxes of cake mix gave these shelf lives (in days): 215, 217, 218, 219, 216, 217, 217, 218, and 218. Using α = 0.025, has the shelf life of the cake mix increased?

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A) No, because 217.22 is quite close to 216.

B) Yes, because computed t is less than the critical value.

C) Yes, because computed t is greater than the critical value.

D) No, because computed t lies in the region of acceptance.

81)

A p-value is a probability. ⊚ true ⊚ false

82) The average cost of tuition plus room and board for a small private liberal arts college is reported to be $8,500 per term, but a financial administrator believes that the average cost is higher. A study conducted using 350 small liberal arts colleges showed that the average cost per term is $8,745. The population standard deviation is $1,200. Let α = 0.05. What is the p-value for this test?

A) 0.0500 B) 0 C) 0.0124 D) 0.4938

83) The average cost of tuition plus room and board for a small private liberal arts college is reported to be $9,400 per term, but a financial administrator believes that the average cost is higher. A study conducted using 350 small liberal arts colleges showed that the average cost per term is $9,735. The population standard deviation is $1,200. Let α = 0.05. Based on the computed test statistic or p-value, what is our decision about the average cost?

A) Less than $9,400 B) Not equal to $9,400 C) Equal to $9,400 D) Greater than $9,400

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84) For a one-tailed hypothesis test, the critical z-value of the test statistic is −2.46. Which of the following is true about the hypothesis test?

A) α = 0.01 for an upper-tailed test B) α = 0.05 for a lower-tailed test C) α = 0.05 for an upper-tailed test D) α = 0.01 for a lower-tailed test

85) A hypothesis regarding the weight of newborn infants at a community hospital is that the mean is 6.6 pounds. A sample of seven infants is randomly selected and their weights at birth are recorded as 9.0, 7.3, 6.0, 8.8, 6.8, 8.4, and 6.6 pounds. If α = 0.05, what is the critical value? The population standard deviation is unknown.

A) 0 B) ±1.943 C) ±2.447 D) ±2.365

86)

An example of a hypothesis is: A person is innocent until proven guilty. ⊚ true ⊚ false

87) Sales at a fast-food restaurant average $6,000 per day. The restaurant decided to introduce an advertising campaign to increase daily sales. To determine the effectiveness of the advertising campaign, a sample of 49 days of sales were taken. They found that the average daily sales were $6,400 per day. From past history, the restaurant knew that its population standard deviation is about $1,000. The value of the test statistic is ___________.

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A) 2.800 B) 6,400 C) 1.960 D) 6,000

88) A consumer products company wants to increase the absorption capacity of a sponge.

Based on past data, the average sponge could absorb 3.5 ounces. After the redesign, the absorption amounts of a sample of sponges were (in ounces): 4.1, 3.7, 3.3, 3.5, 3.8, 3.9, 3.6, 3.8, 4.0, and 3.9. At the 0.01 level of significance, what is the decision rule to test if the new design increased the absorption of the sponge?

A) Reject the null hypothesis if computed t is greater than 2.764.

B) Reject the null hypothesis if computed t is greater than 2.821.

C) Reject the null hypothesis if computed t is less than −3.250 or greater than +3.250.

D) Reject the null hypothesis if computed z is 1.960 or larger.

89) A hypothesis regarding the weight of newborn infants at a community hospital is that the mean is 6.6 pounds. A sample of seven infants is randomly selected and their weights at birth are recorded as 9.0, 7.3, 6.0, 8.8, 6.8, 8.4, and 6.6 pounds. What is the alternate hypothesis?

A) H1: µ = 6.6 B) H1: µ > 7.6 C) H1: µ ≥ 6.6 D) H1: µ≠ 6.6

90)

What statement do we make that determines if the null hypothesis is rejected?

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A) Test statistic B) Critical value C) Decision rule D) Alternate hypothesis

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Answer Key Test name: Chap 10_10e_Lind 1) B 2) TRUE 3) D 4) A 5) D 6) D 7) TRUE 8) B 9) D 10) D 11) B 12) A 13) FALSE 14) TRUE 15) A 16) C 17) B 18) A 19) B 20) FALSE 21) B 22) C 23) C 24) D 25) A 26) C Version 1

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27) A 28) A 29) B 30) D 31) C 32) C 33) TRUE 34) FALSE 35) A 36) B 37) A 38) C 39) D 40) D 41) C 42) C 43) C 44) D 45) B 46) A 47) B 48) D 49) C 50) A 51) C 52) C 53) FALSE 54) TRUE 55) C 56) D Version 1

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57) TRUE 58) A 59) B 60) D 61) TRUE 62) B 63) FALSE 64) A 65) A 66) D 67) A 68) B 69) A 70) C 71) TRUE 72) A 73) D 74) A 75) B 76) D 77) D 78) B 79) D 80) C 81) TRUE 82) B 83) D 84) D 85) C 86) TRUE Version 1

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87) A 88) B 89) D 90) C

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CHAPTER 11 1) A recent study focused on the amount of money single men and women save monthly.

The information is summarized here. Assume that the population standard deviations are unknown but equal.

Men Women

Sample Size

Sample Mean

25 30

50 54

Sample Standard Deviation 10 5

At the 0.01 significance level, do women save more money than men? What is the test statistic for this hypothesis?

A) t-statistic B) df-statistic C) p-statistic D) z-statistic

2) Twenty randomly selected statistics students were given 15 multiple-choice questions and 15 open-ended questions, all on the same material. The professor was interested in determining if students scored higher on the multiple-choice questions. This experiment is an example of ________.

A) a test of proportions B) a two-sample test of means C) a one-sample test of means D) a paired t-test

3) A statistics professor wants to compare grades in two different classes of the same course. This is an example of a paired sample. ⊚ true ⊚ false

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4) An investigation of the effectiveness of a training program to improve customer relationships included a pre-training and a post-training customer survey. To compare the differences, they computed post-training survey score minus pre-training survey score. Seven customers were randomly selected and completed both surveys. The results are shown here: Customer A B C D E F G

Pre-training Survey 7 5 11 7 6 5 2

Post-training Survey 8 6 14 12 9 10 5

What is the value of the test statistic?

A) 4.766 B) 4.262 C) 4.214 D) 4.861

5) A recent study focused on the number of times men and women send a Twitter message in a day. The information is summarized here:

Men Women

Sample Size

Sample Mean

25 30

23 28

Population Standard Deviation 5 10

At the 0.01 significance level, we ask if there is a difference in the mean number of times men and women send a Twitter message in a day. Assume that women are Population 1 and men are Population 2. What is the value of the test statistic for this hypothesis test?

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A) 2.668 B) 2.576 C) 2.402 D) 2.672

6) Accounting procedures allow a business to evaluate their inventory costs based on two methods: LIFO (last in first out) or FIFO (first in first out). A manufacturer evaluated its finished goods inventory (in $000s) for five products with the LIFO and FIFO methods. To analyze the difference, they computed FIFO − LIFO for each product. We would like to determine if the LIFO method results in a lower cost of inventory than the FIFO method.

Product 1 2 3 4 5

FIFO (F) 225 119 100 212 248

LIFO (L) 221 100 113 200 245

If you use the 5% level of significance, what is the critical value?

A) ±2.776 B) +1.645 C) +2.262 D) +2.132

7) Which of the following tests is most sensitive in detecting a significant difference in sample means?

A) A hypothesis test based on dependent samples B) A hypothesis test when the population standard deviation is known C) Any hypothesis test based on the t distribution D) A hypothesis test based on independent samples

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8) A recent study focused on the number of times men and women send a Twitter message in a day. The information is summarized here.

Men Women

Sample Size

Sample Mean

25 30

23 28

Population Standard Deviation 5 10

At the 0.01 significance level, we ask if there is a difference in the mean number of times men and women send a Twitter message in a day. Assume that women are population 1 and men are population 2. What is the p-value for this hypothesis test?

A) 0.0164 B) 0.0001 C) 0.0500 D) 0.0082

9) A national manufacturer of ball bearings is experimenting with two different processes for producing precision ball bearings. It is important that the diameters be as close as possible to an industry standard. The output from each process is sampled, and the average error from the industry standard is measured in millimeters. The results are presented here.

Sample mean Standard deviation Sample size

Process A

Process B

2.0 1.0 12

3.0 0.5 14

The researcher is interested in determining whether there is evidence that the two processes yield different average errors. The population standard deviations are unknown but are assumed equal. Assume that Process A is the first population. If we test the null hypothesis at the 1% level of significance, what is the decision?

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A) Fail to reject the null hypothesis and conclude the means are different.

B) Fail to reject the null hypothesis.

C) Reject the null hypothesis and conclude the means are different.

D) Reject the null hypothesis and conclude the means are the same.

10) If we are testing for the difference between two population means for unpaired observations, it is assumed that the sample observations from one population are independent of the sample observations from the other population. ⊚ true ⊚ false

11) Two samples, one of size 33 and the second of size 32, are selected to test the difference between twoindependent population means. How many degrees of freedom are used to find the critical value? Assume the population standard deviations are unknown but equal.

A) 63 B) 65 C) 64 D) 33

12) A recent study focused on the amount of money single men and women save monthly.

The information is summarized here. Assume that the population standard deviations are unknown but equal.

Men Women

Sample Size

Sample Mean

25 30

50 54

Sample Standard Deviation 10 5

At the 0.01 significance level, do women save more money than men? What is the value of the test statistic for this hypothesis test?

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A) +2.326 B) +1.924 C) +1.819 D) +2.399

13) Use the following table to determine whether or not there is a significant difference between the average hourly wages at two manufacturing companies. Assume a level of significance of 0.05.

Manufacturer 1 n1 = 81

Manufacturer 2 n2 = 64

The p-value is ________.

A) 0.0336 B) 0.4664 C) 1.960 D) 0.0672

14) A company is researching the effectiveness of a new website design to decrease the time to access a website. Five website users were randomly selected, and their times (in seconds) to access the website with the old and new designs were recorded. To compare the times, they computed new website design time minus old website design time. The company wishes to test its hypothesis at the 0.01 level of significance. The results are shown here: User A B C D E

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Old Website Design 30 45 25 32 28

New Website Design 25 30 20 30 27

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What is the value of the test statistic?

A) −2.256 B) −1.895 C) −3.747 D) −2.447

15) A district sales manager wishes to determine whether there is a difference in mean daily sales volume between two stores in his district. He collects daily sales volume for the month of June to do the analysis. Assume that the population standard deviations are unknown and unequal. The hypothesis test is to be conducted using the 0.01 level of significance. Partial output of his results from Excel can be found in the table below:

Sample size (n) Sample mean daily sales volume (in $1,000) Sample standard deviation (in $1,000) Degrees of freedom

Store 1

Store 2

30 15

30 19

5.2 56

6.1

What conclusion should we draw based on the sample evidence?

A) Reject the alternate hypothesis and conclude the means are equal.

B) Fail to reject the null hypothesis and conclude the means are equal.

C) Fail to reject the null hypothesis.

D) Reject the null hypothesis and conclude the means are different.

16) A national manufacturer of ball bearings is experimenting with two different processes for producing precision ball bearings. It is important that the diameters be as close as possible to an industry standard. The output from each process is sampled, and the average error from the industry standard is measured in millimeters. The results are presented here:

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Process A

Process B

2.0 1.0 12

3.0 0.5 14

Sample mean Standard deviation Sample size

The researcher is interested in determining whether there is evidence that the two processes yield different average errors. Assume that Process A is the first population. The population standard deviations are unknown but are assumed equal. What are the degrees of freedom?

A) 24 B) 10 C) 26 D) 13

17) Use the following table to determine whether or not there is a significant difference between the average hourly wages at two manufacturing companies. Assume a level of significance of 0.05.

Manufacturer 1 n1 = 81

Manufacturer 2 n2 = 64

What is the test statistic for the difference between the means?

A) 1.977 B) 1.287 C) 1.834 D) 1.960

18) A recent study focused on the number of times men and women send a Twitter message in a day. The information is summarized here.

Sample Size

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Sample Mean

Population Standard Deviation

8

Men Women

25 30

23 28

5 10

Assume that women are population 1 and men are population 2. At the 0.05 significance level, is there a difference in the mean number of times men and women send a Twitter message in a day? Based on the p-value, what is your conclusion?

A) Fail to reject the null hypothesis.

B) Reject the null hypothesis and conclude the means are different.

C) Fail to reject the null hypothesis and conclude the means are different.

D) Reject the null hypothesis and conclude the means are the same.

19) An investigation of the effectiveness of a training program to improve customer relationships included a pre-training and a post-training customer survey. To compare the differences, they computed post-training survey score minus pre-training survey score. Seven customers were randomly selected and completed both surveys. The results are shown here: Customer A B C D E F G

Pre-training Survey 6 5 10 7 6 5 2

Post-training Survey 8 5 10 10 8 6 8

What is the value of the test statistic?

A) 1.895 B) 2.542 C) 1.943 D) 2.447

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20) The results of a mathematics placement exam at two different campuses of Mercy College follow: Campus 1 2

Sample Size 330 310

Sample Mean 33 31

Population Standard Deviation 8 7

The college wants to test the hypothesis that the mean score on Campus 1 is higher than on Campus 2. If we test the null hypothesis at the 5% level of significance, what is the decision?

A) Reject the null hypothesis and conclude the means are different.

B) Reject the null hypothesis and conclude the means are the same.

C) Fail to reject the null hypothesis and conclude the means are different.

D) Fail to reject the null hypothesis and conclude the means are the same.

21)

When is it appropriate to use the paired difference t-test?

A) When two independent samples are compared B) When four samples are compared at once C) When two dependent samples are compared D) When any two samples are compared

22) A national manufacturer of ball bearings is experimenting with two different processes for producing precision ball bearings. It is important that the diameters be as close as possible to an industry standard. The output from each process is sampled, and the average error from the industry standard is measured in millimeters. The results are presented here.

Sample mean Standard deviation Sample size

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Process A

Process B

2.0 1.0 12

3.0 0.5 14

10

The researcher is interested in determining whether there is evidence that the two processes yield different average errors. The population standard deviations are unknown but are assumed equal. This example is what type of test?

A) A one-sample test of means B) A test of proportions C) A paired t-test D) A two-sample test of means

23) A company is researching the effectiveness of a new website design to decrease the time to access a website. Five website users were randomly selected, and their times (in seconds) to access the website with the old and new designs were recorded. To compare the times, they computed new website design time − old website design time. The results follow.

User A B C D E

Old Website Design 30 45 25 32 28

New Website Design 25 30 20 30 27

What is the alternate hypothesis?

A) H1: µd = 0 B) H1: µd < 0 C) H1: µd ≠ 0 D) H1: µd > 0

24) For a hypothesis test comparing twoindependent population means, the combined degrees of freedom is 38. Which of the following statements about the two sample sizes cannot be true?

Assume the population standard deviations areunknown but equal.

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A) n1 = 19; n2 = 21 B) n1 = 18; n2 = 20 C) n1 = 17; n2 = 23 D) n1 = 20; n2 = 20

25) A company is researching the effectiveness of a new website design to decrease the time to access a website. Five website users were randomly selected, and their times (in seconds) to access the website with the old and new designs were recorded. To compare the times, they computed new website design time minus old website design time. The company wishes to test its hypothesis at the 0.01 level of significance. The results are shown here: User A B C D E

Old Website Design 27 50 24 34 29

New Website Design 25 31 25 28 26

What is the value of the test statistic?

A) −1.665 B) −3.156 C) −1.856 D) −1.304

26) A recent study focused on the amount of money single men and women save monthly.

The information is summarized here. Assume that the population standard deviations are unknown but equal.

Men Women

Version 1

Sample Size

Sample Mean

25 30

50 54

Sample Standard Deviation 10 5

12

At the 0.01 significance level, do women save more money than men? What is the critical value for this hypothesis test?

A) +1.924 B) +2.326 C) +2.399 D) +2.672

27) A recent study focused on the number of times men and women send a Twitter message in a day. The information is summarized here.

Men Women

Sample Size

Sample Mean

25 30

23 28

Population Standard Deviation 5 10

Assume that women are population 1 and men are population 2. At the 0.01 significance level, is there a difference in the mean number of times men and women send a Twitter message in a day? Based on the p-value, what is your conclusion?

A) Reject the null hypothesis and conclude the means are the same.

B) Fail to reject the null hypothesis and conclude the means are different.

C) Reject the null hypothesis and conclude the means are different.

D) Fail to reject the null hypothesis.

28) Consider independent simple random samples that are taken to test the difference between the means of two populations. The variances of the populations are unknown but are assumed to be equal. The sample sizes of each population are n1 = 37 and n2 = 45. The appropriate distribution to use is the ________.

A) t-distribution with df = 41 B) t-distribution with df = 80 C) t-distribution with df = 82 D) t-distribution with df = 81

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29) Two samples, one of size 14 and the second of size 13, are selected to test the difference between twoindependent population means. How many degrees of freedom are used to find the critical value? Assume the population standard deviations are unknown but equal.

A) 26 B) 14 C) 25 D) 27

30) If we are testing for the difference between two population means and assume that the two populations have equal but unknown standard deviations, the sample standard deviations are pooled to compute the best estimated variance. ⊚ true ⊚ false

31) The results of a mathematics placement exam at two different campuses of Mercy College follow: Campus 1 2

Sample Size 330 310

Sample Mean 33 31

Population Standard Deviation 8 7

What is the alternative hypothesis if we want to test the hypothesis that the mean score on Campus 1 is higher than on Campus 2?

A) H1: µ1 ≤ µ2 B) H1: µ1 ≠ µ2 C) H1: µ1 < µ2 D) H1: µ1 > µ2

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32) If the null hypothesis that two means are equal is true, where will 97% of the computed zvalues lie between?

A) ±2.17 B) ±2.07 C) ±2.33 D) ±2.58

33) An investigation of the effectiveness of a training program to improve customer relationships included a pre-training and a post-training customer survey. To compare the differences, they computed post-training survey score − pre-training survey score. Seven customers were randomly selected and completed both surveys. The results are shown here.

Customer A B C D E F G

Pre-training Survey 6 5 10 7 6 5 2

Post-training Survey 8 5 10 10 8 6 8

This analysis is an example of ________.

A) a two-sample test of means B) a one-sample test of means C) a test of proportions D) a paired t-test

34) Use the following table to determine whether or not there is a significant difference between the average hourly wages at two manufacturing companies. Assume a level of significance of 0.05.

Manufacturer 1 n1 = 101

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Manufacturer 2 n2 = 84

15

What is the test statistic for the difference between the means?

A) 2.070 B) 1.523 C) 2.213 D) 2.196

35) The following table shows sample salary information for employees with bachelor's and associate’s degrees for a large company in the Southeast United States:

Sample size (n) Sample mean salary (in $1,000) Population variance (σ2)

Bachelor's

Associate's

81 60 175

49 51 90

The point estimate of the difference between the means of the two populations is ________.

A) 32 B) 4.5 C) −4.5 D) 9

36) The results of a mathematics placement exam at two different campuses of Mercy College follow: Campus 1 2

Sample Size 341 321

Sample Mean 44 42

Population Standard Deviation 8 7

The college wants to test the hypothesis that the mean score on Campus 1 is higher than on Campus 2 using a 0.05 level of significance. What is the computed value of the test statistic?

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A) 3.428 B) 1.674 C) 2.615 D) 3.457

37) A national manufacturer of ball bearings is experimenting with two different processes for producing precision ball bearings. It is important that the diameters be as close as possible to an industry standard. The output from each process is sampled and the average error from the industry standard is measured in millimeters. The results are presented here.

Sample mean Standard deviation Sample size

Process A

Process B

2.0 1.0 12

3.0 0.5 14

The researcher is interested in determining whether there is evidence that the two processes yield different average errors. The population standard deviations are unknown but are assumed equal. Assume that Process A is the first population. What is the computed p-value?

A) 0.17% B) 0.67% C) 5.0% D) 0.30%

38)

Which of the following are most likely to be dependent samples?

A) A study that compares the mean wait times at two different hospital emergency

rooms B) A study that compares the weight gain for puppies who eat two different brands of food C) A study that compares standardized test scores before and after a course is taken D) A study that compares the salaries earned by men and women in the same job position

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39) A company is researching the effectiveness of a new website design to decrease the time to access a website. Five website users were randomly selected, and their times (in seconds) to access the website with the old and new designs were recorded. To compare the times, they computed new website design time minus old website design time. The results are shown here: User A B C D E

Old Website Design 30 45 25 32 28

New Website Design 25 30 20 30 27

For a 0.01 significance level, what is the decision regarding the hypothesis that the training was effective in improving customer relationships?

A) Fail to reject the null hypothesis.

B) Reject the null hypothesis and conclude that the new design reduced the mean access times.

C) Reject the null hypothesis and conclude that the new design did not reduce the mean access times.

D) Fail to reject the null hypothesis and conclude that the new design did not reduce the mean access times.

40) Accounting procedures allow a business to evaluate its inventory costs based on two methods: LIFO (last in first out) or FIFO (first in first out). A manufacturer evaluated its finished goods inventory (in $000s) for five products with the LIFO and FIFO methods. To analyze the difference, they computed FIFO minus LIFO for each product. We would like to determine if the LIFO method results in a lower cost of inventory than the FIFO method. The company wishes to test this hypothesis at the 0.05 level of significance.

Product 1 2 3 4 5

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FIFO (F) 228 122 102 217 251

LIFO (L) 216 105 116 201 247 18

What is the value of the test statistic?

A) +1.222 B) +0.76 C) ±3.065 D) +2.421

41) When testing the hypothesized equality of two population means, the implied null hypothesis is ________.

A) H0: µ1 = 0 B) H0: µ1 − µ2 ≠ 0 C) H0: µ1 − µ2 = 0 D) H0: µ2 = 0

42) Accounting procedures allow a business to evaluate their inventory costs based on two methods: LIFO (last in first out) or FIFO (first in first out). A manufacturer evaluated its finished goods inventory (in $000s) for five products with the LIFO and FIFO methods. To analyze the difference, they computed FIFO − LIFO for each product. We would like to determine if the LIFO method results in a lower cost of inventory than the FIFO method.

Product 1 2 3 4 5

FIFO (F) 225 119 100 212 248

LIFO (L) 221 100 113 200 245

What is the null hypothesis?

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A) H0: µd ≤ 0 B) H0: µd = 0 C) H0: µd ≠ 0 D) H0: µd ≥ 0

43) For a hypothesis comparing twoindependent population means, H0: μ1 ≤ μ2, what is the critical value for a one-tailed hypothesis test, using a 5% significance level, with both sample sizes equal to 13? Assume the population standard deviations are unknown but equal.

A) +2.064 B) ±1.711 C) +1.711 D) +2.060

44) A recent study focused on the amount of money single men and women save monthly.

The information is summarized here. Assume that the population standard deviations are unknown but equal.

Men Women

Sample Size

Sample Mean

25 30

50 54

Population Standard Deviation 10 5

At the 0.01 significance level, what is your conclusion about whether women save more money than men?

A) Fail to reject the null hypothesis and conclude the means are different.

B) Fail to reject the null hypothesis.

C) Reject the null hypothesis and conclude that women save more than men.

D) Reject the null hypothesis and conclude that women and men save the same amount.

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45) When dependent samples are used to test for differences in the means, we compute paired differences. ⊚ true ⊚ false

46) A company is researching the effectiveness of a new website design to decrease the time to access a website. Five website users were randomly selected, and their times (in seconds) to access the website with the old and new designs were recorded. To compare the times, they computed new website design time minus old website design time. The results are shown here: User A B C D E

Old Website Design 29 47 23 34 28

New Website Design 25 31 22 27 25

For a 0.01 significance level, what is the decision regarding the hypothesis that the training was effective in improving customer relationships?

A) Reject the null hypothesis and conclude that the new design did not reduce the mean access times.

B) Fail to reject the null hypothesis.

C) Fail to reject the null hypothesis and conclude that the new design did not reduce the mean access times.

D) Reject the null hypothesis and conclude that the new design reduced the mean access times.

47) An investigation of the effectiveness of a training program to improve customer relationships included a pre-training and a post-training customer survey. To compare the differences, they computed post-training survey score − pre-training survey score. Seven customers were randomly selected and completed both surveys. The results are shown here.

Customer A B

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Pre-training Survey 6 5

Post-training Survey 8 5 21

C D E F G

10 7 6 5 2

10 10 8 6 8

For a 0.05 significance level, what is the critical value?

A) 1.645 B) 2.447 C) 1.943 D) 1.895

48) A national manufacturer of ball bearings is experimenting with two different processes for producing precision ball bearings. It is important that the diameters be as close as possible to an industry standard. The output from each process is sampled and the average error from the industry standard is measured in millimeters. The results are presented here.

Sample mean Standard deviation Sample size

Process A

Process B

2.0 1.0 12

3.0 0.5 14

The researcher is interested in determining whether there is evidence that the two processes yield different average errors. The population standard deviations are unknown, and assumed to be unequal. Assume that Process A is the first population. What is the computed p-value?

A) 5.0% B) 0.17% C) 0.30% D) 0.67%

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49) A recent study focused on the amount of money single men and women save monthly.

The information is summarized here. Assume that the population standard deviations are unknown but equal.

Men Women

Sample Size

Sample Mean

25 30

50 54

Sample Standard Deviation 10 5

At the 0.01 significance level, do women save more money than men? What is the p-value for this hypothesis test?

A) 3.44% B) 5.09% C) 2.99% D) 0.03%

50) When dependent samples are used to test for differences in the means, we pool the sample variances. ⊚ true ⊚ false

51) For a hypothesis test comparing twoindependent population means, the combined degrees of freedom is 24. Which of the following statements about the two sample sizes cannot be true?

Assume the population standard deviations areunknown but equal.

A) n1 = 10; n2 = 16 B) n1 = 12; n2 = 14 C) n1 = 11; n2 = 13 D) n1 = 13; n2 = 13

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52) A national manufacturer of ball bearings is experimenting with two different processes for producing precision ball bearings. It is important that the diameters be as close as possible to an industry standard. The output from each process is sampled and the average error from the industry standard is measured in millimeters. The results are presented here.

Process A

Process B

2.0 1.0 12

3.0 0.5 14

Sample mean Standard deviation Sample size

The researcher is interested in determining whether there is evidence that the two processes yield different average errors. The population standard deviations are unknown but are assumed equal. Assume that Process A is the first population. What is the computed value of t?

A) −3.299 B) +0.5938 C) −1.000 D) +2.797

53) A company is researching the effectiveness of a new website design to decrease the time to access a website. Five website users were randomly selected, and their times (in seconds) to access the website with the old and new designs were recorded. To compare the times, they computed new website design time − old website design time. The results follow.

User A B C D E

Old Website Design 30 45 25 32 28

New Website Design 25 30 20 30 27

For a 0.01 significance level, what is the critical value?

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A) −2.447 B) −2.256 C) −1.895 D) −3.747

54) Use the following table to determine whether or not there is a significant difference between the average hourly wages at two manufacturing companies. Assume a level of significance of 0.05.

Manufacturer 1 n1 = 81

Manufacturer 2 n2 = 64

What is the critical value of this test?

A) ±1.977 B) ±1.960 C) +1.834 D) +1.645

55) A recent study focused on the number of times men and women send a Twitter message in a day. The information is summarized here:

Men Women

Sample Size

Sample Mean

27 32

25 30

Population Standard Deviation 5 10

At the 0.01 significance level, we ask if there is a difference in the mean number of times men and women send a Twitter message in a day. Assume that women are Population 1 and men are Population 2. What is the value of the test statistic for this hypothesis test?

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25

A) 2.754 B) 2.658 C) 2.484 D) 2.750

56) Accounting procedures allow a business to evaluate its inventory costs based on two methods: LIFO (last in first out) or FIFO (first in first out). A manufacturer evaluated its finished goods inventory (in $000s) for five products with the LIFO and FIFO methods. To analyze the difference, they computed FIFO − LIFO for each product. Based on the following results, does the LIFO method result in a lower cost of inventory than the FIFO method?

Product 1 2 3 4 5

FIFO (F) 225 119 100 212 248

LIFO (L) 221 100 113 200 245

This example is what type of test?

A) A two-sample test of means B) A test of proportions C) A paired t-test D) A one-sample test of means

57) A recent study focused on the amount of money single men and women save monthly.

The information is summarized here. Assume that the population standard deviations are unknown and not equal.

Men Women

Version 1

Sample Size

Sample Mean

25 30

50 54

Sample Standard Deviation 10 5

26

At the 0.05 significance level, what is your conclusion about whether women save more money than men?

A) Reject the null hypothesis and conclude that women save more than men.

B) Reject the null hypothesis and conclude that women and men save the same amount.

C) Fail to reject the null hypothesis and conclude the means are different.

D) Fail to reject the null hypothesis.

58) We test for a hypothesized difference between two independent population means: H0: μ1 = μ2. The population standard deviations are unknown but assumed equal. There are 25 observations in the first sample and 22 in the second sample. How many degrees of freedom are associated with the critical value?

A) 46 B) 45 C) 47 D) 44

59) A national manufacturer of ball bearings is experimenting with two different processes for producing precision ball bearings. It is important that the diameters be as close as possible to an industry standard. The output from each process is sampled and the average error from the industry standard is measured in millimeters. The results are presented here.

Sample mean Standard deviation Sample size

Process A

Process B

2.0 1.0 12

3.0 0.5 14

The researcher is interested in determining whether there is evidence that the two processes yield different average errors. The population standard deviations are unknown but assumed equal. Assume that Process A is the first population. What is the critical t-value at the 1% level of significance?

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27

A) ±2.779 B) ±2.797 C) −2.492 D) ±1.711

60) A district sales manager wishes to determine whether there is a difference in mean daily sales volume between two stores in his district. He collects daily sales volume for the month of June to do the analysis. Assume that the population standard deviations are unknown and unequal. The hypothesis test is to be conducted using the 0.01 level of significance. Partial output of his results from Excel can be found in the table below:

Sample size (n) Sample mean daily sales volume (in $1,000) Sample standard deviation (in $1,000) Degrees of freedom

Store 1

Store 2

30 15

30 19

5.2 56

6.1

What is the critical value of the test statistic?

A) ±2.667 B) ±1.960 C) −1.645 D) ±2.395

61) If the null hypothesis states that there is no difference between the mean net income of retail stores in Chicago and New York City, then the test is two-tailed. ⊚ true ⊚ false

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62) An investigation of the effectiveness of a training program to improve customer relationships included a pre-training and a post-training customer survey. To compare the differences, they computed (post-training survey score − pre-training survey score). Seven customers were randomly selected and completed both surveys. The results are shown here.

Customer A B C D E F G

Pre-training Survey 6 5 10 7 6 5 2

Post-training Survey 8 5 10 10 8 6 8

For a 0.05 significance level, what is the decision regarding the hypothesis that the training was effective in improving customer relationships?

A) Reject the null hypothesis and conclude that the training was ineffective.

B) Fail to reject the null hypothesis and conclude that the mean survey scores are the same.

C) Reject the null hypothesis and conclude that the training was effective.

D) Fail to reject the null hypothesis and conclude that the mean survey scores are not equal.

63) A company is researching the effectiveness of a new website design to decrease the time to access a website. Five website users were randomly selected, and their times (in seconds) to access the website with the old and new designs were recorded. To compare the times, they computed new website design time − old website design time. The results are shown here.

User A B C D E

Old Website Design 30 45 25 32 28

New Website Design 25 30 20 30 27

What is the null hypothesis?

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A) H0: µd ≤ 0 B) H0: µd ≠ 0 C) H0: µd = 0 D) H0: µd ≥ 0

64) The results of a mathematics placement exam at two different campuses of Mercy College follow: Campus 1 2

Sample Size 330 310

Sample Mean 33 31

Population Standard Deviation 8 7

The college wants to test the hypothesis that the mean score on Campus 1 is higher than on Campus 2 using a 0.05 level of significance. Given that the two population standard deviations are known, what is the p-value?

A) 0.00 B) 0.95 C) 1.00 D) 0.05

65) Use the following table to determine whether or not there is a significant difference between the average hourly wages at two manufacturing companies. Assume a level of significance of 0.05.

Manufacturer 1 n1 = 84

Manufacturer 2 n2 = 67

The p-value is ________.

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30

A) 0.0307 B) 0.0615 C) 0.4693 D) 1.998

66) If two dependent samples of size 20 are used to test the difference between the means, the degrees of freedom for a t-statistic are 19. ⊚ true ⊚ false

67) The results of a mathematics placement exam at two different campuses of Mercy College follow: Campus 1 2

Sample Size 330 310

Sample Mean 33 31

Population Standard Deviation 8 7

The college wants to test the hypothesis that the mean score on Campus 1 is higher than on Campus 2 using a 0.05 level of significance. What is the computed value of the test statistic?

A) 3.400 B) 3.371 C) 2.576 D) 1.645

68) If the null hypothesis states that there is no difference between the mean income of males and the mean income of females, then the test is one-tailed. ⊚ true ⊚ false

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69) The following table shows sample salary information for employees with bachelor's and associate’s degrees for a large company in the Southeast United States:

Sample size (n) Sample mean salary (in $1,000) Population variance (σ2)

Bachelor's

Associate's

107 86 175

62 64 90

The point estimate of the difference between the means of the two populations is ______.

A) 45 B) 11.0 C) −11.0 D) 22

70) A national manufacturer of ball bearings is experimenting with two different processes for producing precision ball bearings. It is important that the diameters be as close as possible to an industry standard. The output from each process is sampled, and the average error from the industry standard is measured in millimeters. The results are presented here:

Sample mean Standard deviation Sample size

Process A

Process B

21.00 1.00 31

22.00 0.5 33

The researcher is interested in determining whether there is evidence that the two processes yield different average errors. Assume that Process A is the first population. The population standard deviations are unknown but are assumed equal. What are the degrees of freedom?

A) 62 B) 64 C) 29 D) 32

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71) A recent study focused on the number of times men and women send a Twitter message in a day. The sample information is summarized here.

Sample Size

Mean

25 30

23 28

Men Women

Population Standard Deviation 5 10

At the 0.01 significance level, we ask if there is a difference in the mean number of times men and women send a Twitter message in a day. What is the test statistic for this hypothesis?

A) df-statistic B) z-statistic C) p-statistic D) t-statistic

72) When testing the difference between two dependent population means, the test statistic is based on a ________.

A) sum of the population variances B) pooled proportion C) standard deviation of the differences D) pooled variance

73) Accounting procedures allow a business to evaluate their inventory costs based on two methods: LIFO (last in first out) or FIFO (first in first out). A manufacturer evaluated its finished goods inventory (in $000s) for five products with the LIFO and FIFO methods. To analyze the difference, they computed FIFO − LIFO for each product. We would like to determine if the LIFO method results in a lower cost of inventory than the FIFO method.

Product 1 2 3 4

Version 1

FIFO (F) 225 119 100 212

LIFO (L) 221 100 113 200

33

5

248

245

What is the alternate hypothesis?

A) H1: µd > 0 B) H1: µd < 0 C) H1: µd ≤ 0 D) H1: µd ≠ 0

74) The results of a mathematics placement exam at two different campuses of Mercy College follow: Campus 1 2

Sample Size 330 310

Sample Mean 33 31

Population Standard Deviation 8 7

What is the null hypothesis if we want to test the hypothesis that the mean score on Campus 1 is higher than on Campus 2?

A) H0: µ1 = µ2 B) H0: µ1 = 0 C) H0: µ1 ≥ µ2 D) H0: µ1 ≤ µ2

75) A national manufacturer of ball bearings is experimenting with two different processes for producing precision ball bearings. It is important that the diameters be as close as possible to an industry standard. The output from each process is sampled, and the average error from the industry standard is measured in millimeters. The results are presented here.

Sample mean Standard deviation Sample size

Version 1

Process A

Process B

2.0 1.0 12

3.0 0.5 14

34

The researcher is interested in determining whether there is evidence that the two processes yield different average errors. The population standard deviations are unknown but are assumed equal. What is the null hypothesis?

A) H0: µA = µB B) H0: µA ≠ µB C) H0: µA ≤ µB D) H0: µA > µB

76) A district sales manager wishes to determine whether there is a difference in mean daily sales volume between two stores in his district. He collects daily sales volume for the month of June to do the analysis. Assume that the population standard deviations are unknown and unequal. The hypothesis test is to be conducted using the 0.01 level of significance. Partial output of his results from Excel can be found in the table below:

Sample size (n) Sample mean daily sales volume (in $1,000) Sample standard deviation (in $1,000) Degrees of freedom

Store 1

Store 2

30 15

30 19

5.2 56

6.1

What is the value of the test statistic?

A) ± 2.667 B) −2.733 C) −2.395 D) +1.960

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77) A recent study focused on the amount of money single men and women save monthly.

The information is summarized here. Assume that the population standard deviations are unknown and not equal.

Men Women

Sample Size

Sample Mean

25 30

50 54

Sample Standard Deviation 10 5

At the 0.01 significance level, do women save more money than men? What is the p-value for this hypothesis test?

A) 3.0% B) 3.44% C) 3.9% D) 0.03%

78) When testing the difference between two independent population means, the sample variances are pooled to estimate the population variance when ________.

A) the population variances are known and equal B) the population variances are assumed unequal and unknown C) the population means are known D) the population variances are assumed equal but unknown

79) A district sales manager wishes to determine whether there is a difference in mean daily sales volume between two stores in his district. He collects daily sales volume for the month of June to do the analysis. Assume that the population standard deviations are unknown and unequal. The hypothesis test is to be conducted using the 0.01 level of significance. Partial output of his results from Excel can be found in the table below:

Sample size (n) Sample mean daily sales volume (in $1,000)

Version 1

Store 1

Store 2

46 31

46 35

36

Sample standard deviation (in $1,000) Degrees of freedom

5.2 90

6.1

What is the value of the test statistic?

A) −3.047 B) −3.385 C) +1.308 D) ± 3.319

80) If we are testing for the difference between two population means and assume that the two populations have equal and unknown standard deviations, the degrees of freedom are computed as (n1)(n2) − 1. ⊚ true ⊚ false

81) Accounting procedures allow a business to evaluate its inventory costs based on two methods: LIFO (last in first out) or FIFO (first in first out). A manufacturer evaluated its finished goods inventory (in $000s) for five products with the LIFO and FIFO methods. To analyze the difference, they computed FIFO minus LIFO for each product. We would like to determine if the LIFO method results in a lower cost of inventory than the FIFO method. The company wishes to test this hypothesis at the 0.05 level of significance.

Product 1 2 3 4 5

FIFO (F) 225 119 100 212 248

LIFO (L) 221 100 113 200 245

What is the value of the test statistic?

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A) ±2.776 B) +0.47 C) +2.132 D) +0.933

82) Accounting procedures allow a business to evaluate their inventory costs based on two methods: LIFO (last in first out) or FIFO (first in first out). A manufacturer evaluated its finished goods inventory (in $000s) for five products with the LIFO and FIFO methods. To analyze the difference, they computed FIFO − LIFO for each product. We would like to determine if the LIFO method results in a lower cost of inventory than the FIFO method.

Product 1 2 3 4 5

FIFO (F) 225 119 100 212 248

LIFO (L) 221 100 113 200 245

What are the degrees of freedom?

A) 4 B) 10 C) 5 D) 15

83) Assuming the population variances are known, the variance of thedistribution of differences between twoindependent population means is ________.

A) the sum of the two sample sizes for each population B) the sum of the two variances of the two sampling distributions C) the sum of the two standarddeviations of the two sampling distributions D) the sum of the two means

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84) The net weights (in grams) of a sample of bottles filled by a machine manufactured by Edne, and the net weights of a sample filled by a similar machine manufactured by Orno, Incorporated, are shown here.

Edne

8

7

6

9

7

5

Orno

10

7

11

9

12

14

9

8

Testing the claim at the 0.05 level that the mean weight of the bottles filled by the Orno machine is greater than the mean weight of the bottles filled by the Edne machine, what is the critical value? Assume unknown but equal population standard deviations for both samples.

A) +1.782 B) +2.145 C) +1.761 D) +2.179

85) Accounting procedures allow a business to evaluate its inventory costs based on two methods: LIFO (last in first out) or FIFO (first in first out). A manufacturer evaluated its finished goods inventory (in $000s) for five products with the LIFO and FIFO methods. To analyze the difference, they computed FIFO − LIFO for each product. Based on the following results, does the LIFO method result in a lower cost of inventory than the FIFO method?

Product 1 2 3 4 5

FIFO (F) 225 119 100 212 248

LIFO (L) 221 100 113 200 245

What is the decision at the 5% level of significance?

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A) Fail to reject the null hypothesis.

B) Reject the null hypothesis and conclude LIFO is more effective.

C) Fail to reject the null hypothesis and conclude LIFO is more effective.

D) Reject the alternate hypothesis and conclude LIFO is more effective.

86) We test for a hypothesized difference between two independent population means: H0: μ1 = μ2. The population standard deviations are unknown but assumed equal. There are 15 observations in the first sample and 12 in the second sample. How many degrees of freedom are associated with the critical value?

A) 26 B) 24 C) 25 D) 27

87) When the standard deviations are equal but unknown, a test for the differences between two population means has n − 1 degrees of freedom. ⊚ true ⊚ false

88) A national manufacturer of ball bearings is experimenting with two different processes for producing precision ball bearings. It is important that the diameters be as close as possible to an industry standard. The output from each process is sampled, and the average error from the industry standard is measured in millimeters. The results are presented here.

Sample mean Standard deviation Sample size

Version 1

Process A

Process B

2.0 1.0 12

3.0 0.5 14

40

The researcher is interested in determining whether there is evidence that the two processes yield different average errors. The population standard deviations are unknown but assumed equal. What is the alternate hypothesis?

A) H1: µA ≤ µB B) H1: µA = µB C) H1: µA > µB D) H1: µA ≠ µB

89) Which condition must be met to conduct a test for the difference in two sample means using a z-statistic?

A) The samples are dependent.

B) The data must be at least of nominal scale.

C) The populations must be normal.

D) The two population standard deviations must be known.

90) Consider independent simple random samples that are taken to test the difference between the means of two populations. The variances of the populations are unknown but are assumed to be equal. The sample sizes of each population are n1 = 50 and n2 = 58. The appropriate distribution to use is the ________.

A) t-distribution with df = 107 B) t-distribution with df = 106 C) t-distribution with df = 108 D) t-distribution with df = 54

91) Use the following table to determine whether or not there is a significant difference between the average hourly wages at two manufacturing companies. Assume a level of significance of 0.05.

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41

Manufacturer 1 n1 = 81

Manufacturer 2 n2 = 64

What conclusion should we draw based on the sample evidence?

A) Reject the null hypothesis and conclude the means are different.

B) Reject the alternate hypothesis and conclude the means are equal.

C) Fail to reject the null hypothesis.

D) Fail to reject the null hypothesis and conclude the means are equal.

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Answer Key Test name: Chap 11_10e_Lind 1) A 2) D 3) FALSE 4) D 5) C 6) D 7) A 8) A 9) C 10) TRUE 11) A 12) B 13) D 14) A 15) D 16) A 17) C 18) B 19) B 20) A 21) C 22) D 23) B 24) B 25) A 26) C Version 1

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27) D 28) B 29) C 30) TRUE 31) D 32) A 33) D 34) A 35) D 36) A 37) D 38) C 39) A 40) A 41) C 42) A 43) C 44) B 45) TRUE 46) B 47) C 48) D 49) C 50) FALSE 51) C 52) A 53) D 54) B 55) C 56) C Version 1

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57) A 58) B 59) B 60) A 61) TRUE 62) C 63) D 64) A 65) B 66) TRUE 67) B 68) FALSE 69) D 70) A 71) B 72) C 73) A 74) D 75) A 76) B 77) C 78) D 79) B 80) FALSE 81) D 82) A 83) B 84) A 85) A 86) C Version 1

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87) FALSE 88) D 89) D 90) B 91) C

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CHAPTER 12 1) A manufacturer of automobile transmissions uses three different processes. Management ordered a study of the production costs to see if there is a difference among the three processes.

A summary of the findings is shown here:

Process totals ($100s) Sample size Sum of squares

Process 1

Process 2

Process 3

Total

137

108

107

352

10 1,893

10 1,188

10 1,175

30 4,256

In an ANOVA table, what are the total degrees of freedom?

A) 27 B) 29 C) 30 D) 28

2) Several employees have submitted different methods of assembling a subassembly.

Sample data for each method are: Minutes Required for Assembly Sample Number Lind's Method Szabo's Method Carl's Method Manley's Method 1 16.6 22.4 31.4 18.4 2 17.0 21.5 33.4 19.6 3 16.9 22.6 30.1 17.6

How many treatments are there?

A) 12 B) 0 C) 4 D) 3

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3)

What distribution does the F-distribution approach as the sample size increases?

A) Poisson B) Normal C) Binomial D) Exponential

4) Two accounting professors decided to compare the variance of their grading procedures.

To accomplish this, they each graded the same 10 exams, with the following results:

Professor 1 Professor 2

Mean Grade

Standard Deviation

79.3 82.1

22.4 12.0

What is the critical value of F at the 0.02 level of significance assuming a two-tail test?

A) 4.85 B) 4.33 C) 6.51 D) 5.35

5) A large department store examined a sample of 18 credit card sales and recorded the amounts charged for each of three types of credit cards: MasterCard, Visa, and Discover. Six MasterCard sales, seven Visa, and five Discover sales were recorded. The store used an ANOVA to test if the mean sales for each credit card were equal. What are the degrees of freedom for the F-statistic?

A) 6 in the numerator, 15 in the denominator B) 2 in the numerator, 15 in the denominator C) 3 in the numerator, 18 in the denominator D) 18 in the numerator, 3 in the denominator

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6) If an ANOVA test is conducted and the null hypothesis is rejected, what does this indicate?

A) All population means are different.

B) The population means are equal.

C) At least one pair of population means is different.

D) The p-value is greater than α.

7)

Given the following ANOVA table for three treatments each with six observations:

Source Treatment

Sum of Squares 1,116

Error

1,068

Total

2,184

df

Mean square

What are the degrees of freedom for the treatment and error sources of variation?

A) 2 and 15 B) 2 and 17 C) 3 and 15 D) 3 and 18

8) Two accounting professors decided to compare the variance of their grading procedures.

To accomplish this, they each graded the same 10 exams, with the following results:

Professor 1 Professor 2

Mean Grade

Standard Deviation

79.3 82.1

22.4 12.0

At the 2% level of significance, what is the decision regarding the two variances being equal?

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A) Fail to reject the null hypothesis.

B) Reject the null hypothesis and conclude the variances are the same.

C) Reject the null hypothesis and conclude the variances are different.

D) Fail to reject the null hypothesis and conclude the variances are different.

9) To employ Analysis of Variance (ANOVA), the populations being studied must be approximately normally distributed. ⊚ true ⊚ false

10) Two accounting professors decided to compare the variance of their grading procedures.

To accomplish this, they each graded the same 10 exams, with the following results:

Professor 1 Professor 2

Mean Grade

Standard Deviation

79.3 82.1

22.4 12.0

What is the null hypothesis?

A) H0 : B) H0 : C) H0 : D) H0:

11) Three different fertilizers were applied to a field of celery. In computing F, how many degrees of freedom are there in the numerator?

A) 1 B) 2 C) 0 D) 3

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12) The annual dividend rates for a random sample of 16 companies in three different industries, utilities, banking, and insurance, were recorded. The ANOVA comparing the mean annual dividend rates among three industries rejected the null hypothesis that the dividend rates were equal. The mean square error (MSE) was 3.36. The following table summarizes the results:

Number Sampled Mean Annual Dividend Rate

Utilities

Banking

Insurance

5 11.62

5 15.4

6 17.4

Based on the comparison between the mean annual dividend rates for companies in the insurance and utilities industries, ________.

A) the ANOVA results show that the mean annual dividend rates are significantly different B) the ANOVA results show that the mean annual dividend rates are not significantly different C) a 95% confidence interval shows that the mean annual dividend rates are significantly different D) a 95% confidence interval shows that the mean annual dividend rates are not significantly different

13) A preliminary study of hourly wages paid to unskilled employees in three metropolitan areas was conducted. Seven employees were included from Area A, nine from Area B, and twelve from Area C. The test statistic was computed to be 4.91. What can we conclude at the 0.05 level?

A) The mean hourly wages of unskilled employees of all areas are equal.

B) None of these is correct.

C) More degrees of freedom are needed.

D) The mean hourly wages in at least two metropolitan areas are different.

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14) An ANOVA procedure is applied to data obtained from four distinct populations. The samples, each comprised of 18 observations, were taken from the four populations. The degrees of freedom for the numerator and denominator for the critical value of F are ________.

A) 3 and 71, respectively B) 4 and 72, respectively C) 3 and 68, respectively D) 4 and 24, respectively

15) When testing for differences between treatment means, the degrees of freedom for the tstatistic are ________.

A) (1 ÷ n1 + 1 ÷ n2) B) (n − k) C) k D) (n − 1)

16)

Analysis of variance is used to ________.

A) simultaneously compare several population means B) compare nominal data C) compare population proportions D) compute a test

17) A recent study focused on the amount of money single men and women save monthly.

The information is summarized here.

Men Women

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Sample Size

Sample Mean

25 30

50 54

Sample Standard Deviation 10 8

6

At the 0.05 significance level, are the variances for what women save different than what men save? What is the p-value for this hypothesis test?

A) 3.0% B) 5.09% C) 3.44% D) 12.5%

18) The annual dividend rates for a random sample of 16 companies in three different industries, utilities, banking, and insurance, were recorded. The ANOVA comparing the mean annual dividend rates among three industries rejected the null hypothesis that the dividend rates were equal. The mean square error (MSE) was 3.36. The following table summarizes the results:

Number Sampled Mean Annual Dividend Rate

Utilities

Banking

Insurance

5 11.62

5 15.4

6 17.4

When comparing the mean annual dividend rates for companies in the insurance and utilities industries, which of the following 95% confidence intervals can be constructed?

A) 5.78 ± 2.160 × 1.11 B) 5.78 ± 2.120 × 2.40 C) 5.78 ± 2.120 × 1.11 D) 5.78 ± 2.160 × 2.40

19)

Given the following ANOVA table for three treatments each with six observations:

Source Treatment

Sum of Squares 1,116

Error

1,068

Total

2,184

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df

Mean square

7

What is the decision regarding the null hypothesis at the 5% significance level?

A) Fail to reject H0 -- there is a difference in errors.

B) Reject H0 -- there is a difference in errors.

C) Fail to reject H0 -- there is a difference in treatment means.

D) Reject H0 -- there is a difference in treatment means.

20)

The following is the ANOVA table for three treatments each with six observations:

Source Treatment Error Total

Sum of Squares 1,116 1,068 2,184

What is the treatment mean square?

A) 71.2 B) 558 C) 534 D) 71.4

21) A recent study focused on the number of times men and women send a Twitter message in a day. The information is summarized here.

Men Women

Sample Size

Sample Mean

25 30

23 28

Population Standard Deviation 5 10

At the 0.01 significance level, we ask if there is a difference in the variances of the number of times men and women send a Twitter message in a day. Based on the p-value, what is your conclusion?

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A) Reject the null hypothesis and conclude the variances are the same.

B) Fail to reject the null hypothesis and conclude the variances are different.

C) Reject the null hypothesis and conclude the variances are different.

D) Fail to reject the null hypothesis.

22) A recent study focused on the number of times men and women send a Twitter message in a day. The information is summarized here.

Sample Size

Sample Mean

25 30

23 28

Men Women

Sample Standard Deviation 5 10

At the 0.01 significance level, we ask if there is a difference in the variances of the number of times men and women send a Twitter message in a day. What is the p-value for this hypothesis test?

A) 5.0% B) 2.5% C) 0.05% D) 1.0%

23) When testing for differences between treatment means, the t-statistic is based on ________.

A) the error degrees of freedom B) the total degrees of freedom C) the treatment degrees of freedom D) the ratio of treatment and error degrees of freedom

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24) Two accounting professors decided to compare the variance of their grading procedures.

To accomplish this, they each graded the same 10 exams, with the following results: Mean Grade

Standard Deviation

79.3 82.1

22.4 12.0

Professor 1 Professor 2

What is the alternate hypothesis?

A) H1 : B) H1 : C) H1 : D) H1 :

25) Suppose a package delivery company purchased 21 trucks at the same time. Seven trucks were purchased from Manufacturer A, seven from Manufacturer B, and seven from Manufacturer C. The cost of maintaining each truck was recorded. The company used ANOVA to test if the mean maintenance costs of the trucks from each manufacturer were equal. To apply the F-test, how many degrees of freedom must be in the denominator?

A) 18 B) 21 C) 2 D) 3

26)

The following is the ANOVA table for three treatments each with six observations:

Source Treatment Error Total

Sum of Squares 1,224 1,176 2,400

What is the treatment mean square?

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A) 78.4 B) 588 C) 78.6 D) 612

27) Two accounting professors decided to compare the variance of their grading procedures.

To accomplish this, they each graded the same 10 exams, with the following results:

Professor 1 Professor 2

Mean Grade

Standard Deviation

79.3 82.1

22.4 12.0

What are the degrees of freedom for the denominator of the F ratio?

A) 9 B) 10 C) 20 D) 18

28) Two accounting professors decided to compare the variance of their grading procedures.

To accomplish this, they each graded the same 10 exams, with the following results:

Professor 1 Professor 2

Mean Grade

Standard Deviation

79.3 82.1

22.4 12.0

What is the critical value of F at the 0.10 level of significance?

A) 3.18 B) 5.35 C) 2.44 D) 4.85

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29) A random sample of 40 companies with assets over $10 million was surveyed and asked to indicate their industry and annual computer technology expense. The ANOVA comparing the average computer technology expenses among three industries rejected the null hypothesis. The mean square error (MSE) was 195. The following table summarizes the results:

Number Sampled Mean Expense (1,000,000s)

Education

Tax Services

Food Services

10 2

14 15.5

16 20

When comparing the mean annual computer technology expenses for companies in the tax services and education industries, which of the following 95% confidence intervals can be constructed?

A) 13.5 ± 2.021 × 13.9 B) 13.5 ± 2.026 × 5.78 C) 13.5 ± 2.021 × 5.78 D) 13.5 ± 2.026 × 13.96

30)

The following is the ANOVA table for three treatments each with six observations:

Source Treatment Error Total

Sum of Squares 1,146 1,158 2,304

What is the computed value of F? A) 8 B) 7.42 C) 8.42 D) 7.06

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31) Two accounting professors decided to compare the variance of their grading procedures.

To accomplish this, they each graded the same 10 exams, with the following results:

Professor 1 Professor 2

Mean Grade

Standard Deviation

79.3 82.1

22.4 12.0

What is the p-value at the 0.05 level of significance for the test that the variances are the same?

A) 5.00% B) 2.44% C) 5.35% D) 3.84%

32) A recent study focused on the amount of money single men and women save monthly.

The information is summarized here.

Men Women

Sample Size

Sample Mean

25 30

50 54

Sample Standard Deviation 10 8

At the 0.05 significance level, are the variances for what women save different than what men save? What is your conclusion?

A) Reject the null hypothesis and conclude the variances are different.

B) Fail to reject the null hypothesis.

C) Fail to reject the null hypothesis and conclude the variances are different.

D) Reject the null hypothesis and conclude the variances are the same.

33) A random sample of 40 companies with assets over $10 million was surveyed and asked to indicate their industry and annual computer technology expense. The ANOVA comparing the average computer technology expense among three industries rejected the null hypothesis. The mean square error (MSE) was 195. The following table summarized the results:

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Number Sampled Mean Expense (1,000,000s)

Education

Tax Services

Food Services

10 2

14 15.5

16 20

Based on the comparison between the mean annual computer technology expense for companies in the food services and tax services industries, the 95% confidence interval shows an interval of −5.85 to 14.85 for the difference. This result indicates that ________.

A) companies in the food service industry spend significantly more than companies in the tax service industry B) there is not enough evidence of a significant difference between the two industry technology expenses C) companies in the food service industry spend significantly less than companies in the tax service industry D) the interval contains a difference of 20.7

34)

An F-statistic is ________.

A) a population parameter B) a ratio of two variances C) the difference between three means D) a ratio of two means

35) When the null hypothesis for an ANOVA analysis comparing four treatment means is rejected, ________.

A) two comparisons of treatment means can be made B) eight comparisons of treatment means can be made C) four comparisons of treatment means can be made D) six comparisons of treatment means can be made

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36) In ANOVA analyses, when the null hypothesis is rejected, we can test for differences between treatment means by ________.

A) adding another treatment B) doing an additional ANOVA C) doing a t-test D) constructing confidence intervals

37) The annual dividend rates for a random sample of 16 companies in three different industries, utilities, banking, and insurance, were recorded. The ANOVA comparing the mean annual dividend rate among three industries rejected the null hypothesis that the dividend rates were equal. The mean square error (MSE) was 3.36. The following table summarized the results:

Number Sampled Mean Annual Dividend Rate

Utilities

Banking

Insurance

5 11.62

5 15.4

6 17.4

Based on the comparison between the mean annual dividend rate for companies in banking and utilities, the 95% confidence interval shows an interval of 1.28 to 6.28 for the difference. This result indicates that ________.

A) the annual dividend rate in the banking industry is significantly less than the annual dividend rate in the utilities industry B) the interval contains a difference of 5.00 C) the annual dividend rate in the banking industry is significantly more than the annual dividend rate in the utilities industry D) there is no significant difference between the two rates

38) Two accounting professors decided to compare the variance of their grading procedures.

To accomplish this, they each graded the same 10 exams, with the following results:

Professor 1 Professor 2

Version 1

Mean Grade

Standard Deviation

79.3 82.1

23.5 13.1 15

The calculated F ratio is ________.

A) 2.92 B) 5.09 C) 1.74 D) 3.22

39) A manufacturer of automobile transmissions uses three different processes. Management ordered a study of the production costs to see if there is a difference among the three processes.

A summary of the findings is shown next.

Process totals ($100s) Sample size Sum of squares

Process 1

Process 2

Process 3

Total

137

108

107

352

10 1,893

10 1,188

10 1,175

30 4,256

In an ANOVA table, what are the degrees of freedom for the error source of variation?

A) 30 B) 27 C) 10 D) 3

40) Suppose an automobile manufacturer designed a radically new lightweight engine and wants to recommend the grade of gasoline that will have the best fuel economy. The four grades are regular, economy, premium, and super premium. The test car made three trial runs on the test track using each of the four grades. The miles per gallon were recorded for each grade. At the 0.05 level, what is the critical value of F used to test the hypothesis that the miles per gallon for each fuel are the same?

Regular 39.31

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Kilometers per Liter Economy Premium 36.69 38.99

Super Premium 40.04 16

39.87 39.87

40.00 41.01

40.02 39.99

39.89 39.93

A) 1.96 B) 2.33 C) 12.00 D) 4.07

41)

The F-distribution's curve is positively skewed. ⊚ true ⊚ false

42) In an ANOVA problem involving three treatments and 19 observations per treatment, SSE = 648. The MSE for this scenario is _______.

A) 216 B) 54 C) 29.5 D) 12

43) A manufacturer of automobile transmissions uses three different processes. Management ordered a study of the production costs to see if there is a difference among the three processes.

A summary of the findings is shown next.

Process totals ($100s) Sample size Sum of squares

Process 1

Process 2

Process 3

Total

137

108

107

352

10 1,893

10 1,188

10 1,175

30 4,256

In an ANOVA table, what are the degrees of freedom for the treatment source of variation?

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A) 2 B) 27 C) 3 D) 10

44) When testing for differences between treatment means, a confidence interval is computed with ________.

A) the sum of squared errors B) the mean square error C) the standard deviation D) the standard error of the mean

45) An experiment to determine the most effective way to teach safety principles applied four different teaching methods. Some employees were given programmed instruction booklets and worked through the course at their own pace. Other employees attended lectures. A third group watched a television presentation, and a fourth group was divided into small discussion groups.

A high of 10 was possible. A sample of five tests was selected from each group. The test grade results were: Sample Number Programmed Instruction 1 6 2 7 3 6 4 5 5 6

Lecture 8 5 8 6 8

TV 7 9 6 8 5

Group Discussion 8 5 6 6 5

At the 0.01 level, what is the critical value?

A) 1.96 B) 1.00 C) 5.29 D) 3.24

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46) If we want to determine which treatment means differ, we compute a confidence interval for the difference between each pair of means. ⊚ true ⊚ false

47) The following partial ANOVA table was derived from data having four treatments and a total of 16 observations: Source of Variation Between Treatments Error (Within Treatments)

Sum of Squares 256 192

The mean square between treatments (MST) is ________.

A) 85.33 B) 22.40 C) 48.00 D) 64.00

48) A random sample of 40 companies with assets over $10 million was surveyed and asked to indicate their industry and annual computer technology expense. The ANOVA comparing the average computer technology expenses among three industries rejected the null hypothesis. The mean square error (MSE) was 204. The following table summarizes the results:

Number Sampled Mean Expense (1,000,000s)

Education

Tax Services

Food Services

10 11

14 33.5

16 38

When comparing the mean annual computer technology expenses for companies in the tax services and education industries, which of the following 95% confidence intervals can be constructed?

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A) 22.5 ± 2.026 × 5.914 B) 22.5 ± 2.026 × 22.96 C) 22.5 ± 2.021 × 22.9 D) 22.5 ± 2.021 × 5.914

49) Two accounting professors decided to compare the variance of their grading procedures.

To accomplish this, they each graded the same 10 exams, with the following results:

Professor 1 Professor 2

Mean Grade

Standard Deviation

79.3 82.1

22.4 12.0

At the 10% level of significance, what is the decision regarding the null hypothesis that the variances are equal?

A) Reject the null hypothesis and conclude the variances are the same.

B) Fail to reject the null hypothesis and conclude no significant difference in the variances.

C) Reject the null hypothesis and conclude the variances are different.

D) Fail to reject the null hypothesis.

50) A national manufacturer of ball bearings is experimenting with two different processes for producing precision ball bearings. It is important that the diameters be as close as possible to an industry standard. The output from each process is sampled and the average error from the industry standard is measured in millimeters. The results are presented here.

Sample mean Sample Standard deviation Sample size

Version 1

Process A

Process B

2.0 1.0 12

3.0 0.5 14

20

At the 0.05 significance level, are the variances of the two processes different? What is your conclusion?

A) Reject the null hypothesis and conclude the variances are different.

B) Fail to reject the null hypothesis.

C) Fail to reject the null hypothesis and conclude the variances are different.

D) Reject the null hypothesis and conclude the variances are the same.

51) A random sample of 30 executives from companies with assets over $1 million was selected and asked for their annual income and level of education. The ANOVA comparing the average income among three levels of education rejected the null hypothesis. The mean square error (MSE) was 243.7. The following table summarized the results: High School or Less Number Sampled 7 Mean Salary (1,000s) 49

Undergraduate Degree 11 76.3

Master's Degree or More 12 78.3

When comparing the mean annual incomes for executives with an undergraduate degree and those with a high school education or less, the 95% confidence interval shows an interval of 11.7 to 42.7 for the difference. This result indicates that ________.

A) executives with an undergraduate degree earn significantly more than executives with a high school education or less B) the interval contains a difference of zero C) executives with an undergraduate degree earn significantly less than executives with a high school education or less D) there is no significant difference between the two incomes

52)

The following is the ANOVA table for three treatments each with six observations:

Source Treatment Error

Version 1

Sum of Squares 1,116 1,068

21

Total

2,184

What is the computed value of F? A) 8.84 B) 8.48 C) 7.48 D) 7.84

53) A national manufacturer of ball bearings is experimenting with two different processes for producing precision ball bearings. It is important that the diameters be as close as possible to an industry standard. The output from each process is sampled and the average error from the industry standard is measured in millimeters. The results are presented here.

Sample mean Sample Standard deviation Sample size

Process A

Process B

2.0 1.0 12

3.0 0.5 14

The researcher is interested in determining whether there is a difference in the variances of the two processes. What is the p-value for this hypothesis test?

A) 2.5% B) 1.03% C) 5.0% D) 0.05%

54) The annual dividend rates for a random sample of 16 companies in three different industries, utilities, banking, and insurance, were recorded. The ANOVA comparing the mean annual dividend rates among three industries rejected the null hypothesis that the dividend rates were equal. The mean square error (MSE) was 3.46. The following table summarizes the results:

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Utilities

Banking

Insurance

5 11.78

5 15.80

6 17.6

Number Sampled Mean Annual Dividend Rate

When comparing the mean annual dividend rates for companies in the insurance and utilities industries, which of the following 95% confidence intervals can be constructed?

A) 5.82 ± 2.160 × 1.13 B) 5.82 ± 2.160 × 2.44 C) 5.82 ± 2.120 × 1.13 D) 5.82 ± 2.120 × 2.44

55) To employ ANOVA, the populations should have approximately equal standard deviations. ⊚ true ⊚ false

56) A random sample of 40 companies with assets over $10 million was surveyed and asked to indicate their industry and annual computer technology expense. The ANOVA comparing the average computer technology expenses among three industries rejected the null hypothesis. The mean square error (MSE) was 195. The following table summarizes the results:

Number Sampled Mean Expense (1,000,000s)

Education

Tax Services

Food Services

10 2

14 15.5

16 20

Based on the comparison between the mean annual computer technology expenses for companies in the tax services and education industries, ________.

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A) the ANOVA results show that the mean annual computer technology expenses are not significantly different B) a confidence interval shows that the mean annual computer technology expenses are not significantly different C) the ANOVA results show that the mean annual computer technology expenses are significantly different D) a confidence interval shows that the mean annual computer technology expenses are significantly different

57)

Given the following ANOVA table for three treatments each with six observations:

Source Treatment

Sum of Squares 1,116

Error

1,068

Total

2,184

df

Mean square

What is the critical value of F at the 5% level of significance?

A) 3.29 B) 3.20 C) 3.68 D) 3.59

58) A manufacturer of automobile transmissions uses two different processes. Management ordered a study of the production costs to see if there is a difference between the two processes.

A summary of the findings is shown next.

Process totals ($100s) Sample size Sum of squares

Version 1

Process 1

Process 2

Total

137 10 1,893

108 10 1,188

245 20 3,081

24

What is the critical value of F at the 1% level of significance?

A) 8.18 B) 9.46 C) 8.29 D) 4.61

59) A random sample of 30 executives from companies with assets over $1 million was selected and asked for their annual income and level of education. The ANOVA comparing the average income among three levels of education rejected the null hypothesis. The mean square error (MSE) was 243.7. The following table summarized the results:

Number Sampled Mean Salary (1,000s)

High School or Less 7 49

Undergraduate Degree 11 76.3

Master's Degree or More 12 78.3

Based on the comparison between the mean annual incomes for executives with undergraduate and master's degrees or more, ________.

A) a confidence interval shows that the mean annual incomes are not significantly different B) a confidence interval shows that the mean annual incomes are significantly different C) the ANOVA results show that the mean annual incomes are not significantly different D) the ANOVA results show that the mean annual incomes are significantly different

60) If a confidence interval for the difference between a pair of treatment means includes 0, then we reject the null hypothesis that there is no difference in the pair of treatment means. ⊚ true ⊚ false

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61) A national manufacturer of ball bearings is experimenting with two different processes for producing precision ball bearings. It is important that the diameters be as close as possible to an industry standard. The output from each process is sampled and the average error from the industry standard is measured in millimeters. The results are presented here.

Process A

Process B

2.0 1.0 12

3.0 0.5 14

Sample mean Sample Standard deviation Sample size

At the 0.01 significance level, are the variances of the two processes different? What is your conclusion?

A) Reject the null hypothesis and conclude the variances are different.

B) Fail to reject the null hypothesis.

C) Fail to reject the null hypothesis and conclude the variances are different.

D) Reject the null hypothesis and conclude the variances are the same.

62) The annual dividend rates for a random sample of 16 companies in three different industries, utilities, banking, and insurance, were recorded. The ANOVA comparing the mean annual dividend rates among three industries rejected the null hypothesis that the dividend rates were equal. The mean square error (MSE) was 3.82. The following table summarizes the results:

Number Sampled Mean Annual Dividend Rate

Utilities

Banking

Insurance

5 12.26

5 17.0

6 18.2

Based on the comparison between the mean annual dividend rates for companies in the insurance and utilities industries, ________.

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A) the ANOVA results show that the mean annual dividend rates are significantly different B) a 95% confidence interval shows that the mean annual dividend rates are significantly different C) a 95% confidence interval shows that the mean annual dividend rates are not significantly different D) the ANOVA results show that the mean annual dividend rates are not significantly different

63) The following is the information for a completely randomized experimental design involving four treatments, where 14 observations were recorded for each treatment for a total of 56 observations: SST = 222 (Sum of Squares Between Groups); SS Total = 888 (Sum of Squares Total). The computed value of F, or the test statistic, is ________.

A) 0.25 B) 14.0 C) 5.78 D) 10.0

64) An electronics company wants to compare the quality of their cell phones to the cell phones to three competitors. They sample 10 phones from each company and count the number of defects for each phone. If ANOVA was used to compare the average number of defects, then the treatments would be defined as ________.

A) the four companies B) the total number of phones C) the number of cell phones sampled D) the average number of defects

65) For the hypothesis test, H0: σ12 = σ22, with n1 = 10 and n2 = 10, the F-test statistic is 2.56.

At the 0.02 level of significance, we would reject the null hypothesis.

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⊚ ⊚

66)

true false

ANOVA is a statistical approach used to determine whether or not ________.

A) the means of more than two samples are equal B) the means of two samples are equal C) the means of two or more populations are equal D) the means of two or more samples are equal

67) In an ANOVA table, k represents the total number of sample observations and n represents the total number of treatments. ⊚ true ⊚ false

68) An ANOVA procedure is applied to data obtained from four distinct populations. The samples, each comprised of 15 observations, were taken from the four populations. The degrees of freedom for the numerator and denominator for the critical value of F are ________.

A) 4 and 21, respectively B) 4 and 60, respectively C) 3 and 56, respectively D) 3 and 59, respectively

69) Two accounting professors decided to compare the variance of their grading procedures.

To accomplish this, they each graded the same 10 exams, with the following results:

Professor 1 Professor 2

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Mean Grade

Standard Deviation

79.3 82.1

22.4 12.0

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What are the degrees of freedom for the numerator of the F ratio?

A) 18 B) 9 C) 10 D) 8

70) The following partial ANOVA table was derived from data having four treatments and a total of 16 observations: Source of Variation Between Treatments Error (Within Treatments)

Sum of Squares 270 206

The mean square between treatments (MST) is ________.

A) 23.28 B) 90.00 C) 51.50 D) 64.00

71) <p>The null hypothesis for an ANOVA analysis comparing four treatment means is rejected. The four sample means are The sample size for each treatment is the same. If is significantly different from zero, then ________.

A) is significantly less than and B) and are significantly different</p> C) the treatment means are all equal D) is significantly less than E) the treatment means are all equal

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72) The following is the information for a completely randomized experimental design involving four treatments, where 12 observations were recorded for each treatment for a total of 48 observations: SST = 210 (Sum of Squares Between Groups); SS Total = 840 (Sum of Squares Total). The computed value of F, or the test statistic, is ________.

A) 12.0 B) 0.25 C) 8.0 D) 4.88

73) In an ANOVA problem involving three treatments and 12 observations per treatment, SSE = 297. The MSE for this scenario is ________.

A) 33 B) 9 C) 19.8 D) 99

74) Two accounting professors decided to compare the variance of their grading procedures.

To accomplish this, they each graded the same 10 exams, with the following results: Mean Grade

Standard Deviation

79.3 82.1

22.4 12.0

Professor 1 Professor 2

The calculated F ratio is ________.

A) 3.48 B) 5.35 C) 3.18 D) 1.87

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75) A manufacturer of automobile transmissions uses three different processes. Management ordered a study of the production costs to see if there is a difference among the three processes.

A summary of the findings is shown here:

Process totals ($100s) Sample size Sum of squares

Process 1

Process 2

Process 3

Total

137 12 1,893

108 12 1,188

107 12 1,175

352 36 4,256

In an ANOVA table, what are the total degrees of freedom?

A) 34 B) 33 C) 36 D) 35

76) If the computed value of F is 0.99 and the F critical value is 3.89, we would not reject the null hypothesis. ⊚ true ⊚ false

77) For an ANOVA test, rejecting the null hypothesis does not identify which treatment means differ significantly. ⊚ true ⊚ false

78) A manufacturer of automobile transmissions uses two different processes. Management ordered a study of the production costs to see if there is a difference between the two processes.

A summary of the findings is shown next.

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Process 1

Process 2

Total

137 10 1,893

108 10 1,188

245 20 3,081

Process totals ($100s) Sample size Sum of squares

What is the critical value of F at the 5% level of significance?

A) 4.38 B) 19.45 C) 3.00 D) 4.41

79) A random sample of 40 companies with assets over $10 million was surveyed and asked to indicate their industry and annual computer technology expense. The ANOVA comparing the average computer technology expenses among three industries rejected the null hypothesis. The mean square error (MSE) was 205. The following table summarizes the results:

Number Sampled Mean Expense (1,000,000s)

Education

Tax Services

Food Services

10 12

14 35.5

16 40

Based on the comparison between the mean annual computer technology expenses for companies in the tax services and education industries, ________.

A) the ANOVA results show that the mean annual computer technology expenses are not significantly different B) a confidence interval shows that the mean annual computer technology expenses are significantly different C) a confidence interval shows that the mean annual computer technology expenses are not significantly different D) the ANOVA results show that the mean annual computer technology expenses are significantly different

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80) One characteristic of the F-distribution is that the computed F can only range between −1 and +1. ⊚ true ⊚ false

81)

In ANOVA, the null hypothesis is ________.

A) H0: σ12 = σ22 = σ32 B) H0: μ1 ≠ μ2 ≠ μ3 C) H0: σ12 ≠ σ22 ≠ σ32 D) H0: μ1 = μ2 = μ3

82) Suppose a package delivery company purchased 14 trucks at the same time. Five trucks were purchased from Manufacturer A, four from Manufacturer B, and five from Manufacturer C. The cost of maintaining each truck was recorded. The company used ANOVA to test if the mean maintenance costs of the trucks from each manufacturer were equal. To apply the F-test, how many degrees of freedom must be in the denominator?

A) 14 B) 11 C) 2 D) 3

83) A large department store examined a sample of 30 credit card sales and recorded the amounts charged for each of three types of credit cards: MasterCard, Visa, and Discover. Ten MasterCard sales, eleven Visa, and nine Discover sales were recorded. The store used an ANOVA to test if the mean sales for each credit card were equal. What are the degrees of freedom for the F-statistic?

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A) 2 in the numerator, 27 in the denominator B) 30 in the numerator, 3 in the denominator C) 6 in the numerator, 27 in the denominator D) 3 in the numerator, 30 in the denominator

84)

The alternative hypothesis used in ANOVA is H1: All population means are equal. ⊚ true ⊚ false

85) A random sample of 30 executives from companies with assets over $1 million was selected and asked for their annual income and level of education. The ANOVA comparing the average income among three levels of education rejected the null hypothesis. The mean square error (MSE) was 243.7. The following table summarized the results:

Number Sampled Mean Salary (1,000s)

High School or Less 7 49

Undergraduate Degree 11 76.3

Master's Degree or More 12 78.3

When comparing the mean annual incomes for executives with undergraduate and master's degrees or more, which of the following 95% confidence interval can be constructed?

A) 2.0 ± 3.182 × 42.46 B) 2.0 ± 3.182 × 6.52 C) 2.0 ± 2.052 × 42.46 D) 2.0 ± 2.052 × 6.52

86)

Which statement is correct about the F-distribution?

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A) It is the same as the z-distribution.

B) It cannot be positive.

C) It cannot be negative.

D) It is the same as the t-distribution.

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Answer Key Test name: Chap 12_10e_Lind 1) B 2) C 3) B 4) D 5) B 6) C 7) A 8) A 9) TRUE 10) D 11) B 12) C 13) D 14) C 15) B 16) A 17) D 18) A 19) D 20) B 21) C 22) C 23) A 24) D 25) A 26) D Version 1

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27) A 28) A 29) B 30) B 31) D 32) B 33) B 34) B 35) D 36) D 37) C 38) D 39) B 40) D 41) TRUE 42) D 43) A 44) B 45) C 46) TRUE 47) A 48) A 49) C 50) A 51) A 52) D 53) B 54) A 55) TRUE 56) D Version 1

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57) C 58) C 59) A 60) FALSE 61) B 62) B 63) C 64) A 65) FALSE 66) C 67) FALSE 68) C 69) B 70) B 71) D 72) D 73) B 74) A 75) D 76) TRUE 77) TRUE 78) D 79) B 80) FALSE 81) D 82) B 83) A 84) FALSE 85) D 86) C Version 1

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CHAPTER 13 1) The least squares technique minimizes the sum of the squares of the vertical distances between the actual Y values and the predicted values of Y. ⊚ true ⊚ false

2) A sales manager for an advertising agency believes that there is a relationship between the number of contacts that a salesperson makes and the amount of sales dollars earned. What is the dependent variable?

A) Number of contacts B) Salesperson C) Amount of sales dollars D) Sales manager

3) A hypothesis test is conducted at the 0.05 level of significance to test whether or not the population correlation is zero. If the sample consists of 25 observations and the correlation coefficient is 0.60, what is the computed value of the test statistic? Round to two decimal places.

A) 3.60 B) 2.94 C) 1.96 D) 2.07

4)

Using the following information: Coefficients Intercept Independent variable

−12.8094 2.1794

ANOVA

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df

SS

Regression Residual

1 8

12,323.72 1,334.682

Total

9

13,658.4

MS 12,323.72 136.8553

F 90.0481

What is the coefficient of determination? Round the percentage to one decimal point.

A) 88.4% B) 135.3% C) 90.2% D) 8.1%

5)

What is the test statistic to test the significance of the slope in a regression equation?

A) t-statistic B) π-statistic C) F-statistic D) z-statistic

6)

Using the following information.

Coefficients Intercept Independent variable

−12.8094 2.1794

ANOVA df

SS

Regression Residual

1 8

12,323.56 1,094.842

Total

9

13,418.4

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MS 12,323.56 136.8553

F 90.0481

2

Estimate the value ofŶ when X = 4.

A) 10.45 B) 8.718 C) −4.092 D) 3.73

7) A sales manager for an advertising agency believes there is a relationship between the number of contacts that a salesperson makes and the amount of sales dollars earned. A regression ANOVA shows the following results: ANOVA df

SS

MS

F

Significance F

Regression Residual

1.00 8.00

13,561.92 687.02

13,561.92 86.68

156.38

0.00

Total

9.00

14,248.94

What is the value of the coefficient of correlation?

A) −0.9756 B) +0.6319 C) +0.9515 D) +0.9756

8)

What is the range of values for the coefficient of determination?

A) −1 to +1 inclusive B) −100% to +100% inclusive C) 0% to 100% inclusive D) −100% to 0% inclusive

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9) The Pearson product-moment correlation coefficient, r, requires that variables be measured with ________.

A) a nominal or ratio scale B) an interval or ratio scale C) a nominal or ordinal scale D) an ordinal or ratio scale

10) A sales manager for an advertising agency believes there is a relationship between the number of contacts that a salesperson makes and the amount of sales dollars earned. A regression analysis shows the following results.

Coefficients Standard Error Intercept Number of contacts

−12.201 2.195

6.560 0.176

t-Stat

p-value

−1.860 12.505

0.100 0.000

ANOVA df

SS

MS 13,555.42 86.68

Regression Residual

1.00 8.00

13,555.42 693.48

Total

9.00

14,248.90

Assume that and person making 30 calls is ________.

F 156.38

Significance F 0.00

The 95% prediction interval for a particular

A) 51.4, 55.9 B) 55.8, 51.5 C) 46.7, 60.6 D) 31.1, 76.2

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11) A scatter diagram is a graph that portrays the correlation between a dependent variable and an independent variable. ⊚ true ⊚ false

12) If the correlation coefficient has a negative value, then the coefficient of determination ________.

A) must be positive B) will equal zero C) will also have a negative value D) can take on either a negative or positive value

13)

In the least squares equation, Ŷ = 10 + 20X, the value of 20 indicates ________.

A) the error in prediction B) the Y-intercept increases by 20 units for each unit increase in X C) that X increases by 20 units for each unit increase in Y D) that Y increases by 20 units for each unit increase in X

14) If we reject the null hypothesis, H0:ρ = 0, what can we conclude about the population correlation coefficient?

A) It could be zero.

B) It equals the computed sample correlation.

C) It is not zero.

D) It is zero.

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15) A sales manager for an advertising agency believes there is a relationship between the number of contacts that a salesperson makes and the amount of sales dollars earned. A regression ANOVA shows the following results: ANOVA df

SS

MS

F

Significance F

Regression Residual

1.00 8.00

13,555.42 693.48

13,555.42 86.68

156.38

0.00

Total

9.00

14,248.90

What is the value of the coefficient of determination?

A) 0.9513 B) 0.6319 C) −0.9513 D) 0.9754

16) The regression equation is Ŷ = 30 + 2.56X, the sample size is 14, and the standard error of the slope is 0.97. What is the test statistic to test whether the slope is positive? Assume a level of significance of 0.01.

A) t = +2.639 B) z = +2.576 C) t = +2.681 D) z = −2.236

17) The regression equation is used to estimate a value of the dependent variable Y based on a selected value of the independent variable X. ⊚ true ⊚ false

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18)

What is the null hypothesis to test the significance of the slope in a regression equation?

A) H0: β = 0 B) H0: β≠ 0 C) H0: β ≥ 0 D) H0: β ≤ 0

19)

Which of the following is true about the standard error of estimate?

A) It can be negative.

B) It is a measure of the accuracy of the prediction.

C) It is calculated using the regression mean square.

D) It is based on squared vertical deviations between Y and X.

20) If the coefficient of determination is 0.94, what can we say about the relationship between two variables?

A) The direction of the relationship is negative.

B) Ninety-four percent of the total variation of the dependent variable is explained by the independent variable.

C) The strength of the relationship is 0.94.

D) The direction of the relationship is positive.

21) What are the degrees of freedom used to test the significance of the slope in a simple linear regression equation?

A) n − 2 B) n − 1 C) (n − 1)(n − 2) D) n − 1, n − 2

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22)

Using the following information.

Coefficients

Intercept Independent variable

−12.8094 2.1794

ANOVA df

SS

Regression Residual

1 8

12,323.56 1,094.842

Total

9

13,418.4

MS 12,323.56 136.8553

F 90.0481

The regression equation is ________.

A) X = −12.8094 + 2.1794Ŷ B) Ŷ = 2.1794 − 12.8094X C) 12.8094X = 2.1794Ŷ D) Ŷ= −12.8094 + 2.1794X

23)

The value of the correlation coefficient (r) ________.

A) can be equal to the value of the coefficient of determination (r2) B) can range from −2.0 to +2.0 C) is generally larger than the value of the coefficient of determination D) can never be equal to the value of the coefficient of determination (r2)

24)

Consider a regression and correlation analysis where r2 = 1. We know that ________.

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A) SSE must be greater than one B) SSE must equal to zero C) SSE can take on any negative or positive value D) SSE must be greater than SS Total

25) In regression, if the relationship between the dependent and independent variables is nonlinear, a linear relationship between the variables might be achieved by ________.

A) including an interaction term B) adding another independent variable C) multiplying by 100 D) rescaling the variables

26)

In the regression equation, what does the letter a represent?

A) An error B) The slope of the line C) The Y-intercept D) Any value of the independent variable that is selected

27) The regression equation is Ŷ = 29.29 − 0.96X, the sample size is 8, and the standard error of the slope is 0.22. What is the test statistic to test the significance of the slope?

A) t = −0.960 B) z = −4.364 C) t = −4.364 D) z = +4.364

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28) The regression equation is Ŷ = 29.29 − 0.92X, the sample size is 8, and the standard error of the slope is 0.22. What is the test statistic to test the significance of the slope?

A) t = −4.182 B) z = +4.182 C) z = −4.182 D) t = −0.920

29) A sales manager for an advertising agency believes there is a relationship between the number of contacts that a salesperson makes and the amount of sales dollars earned. A regression analysis shows the following results.

Coefficients Standard Error Intercept Number of contacts

−12.201 2.195

6.560 0.176

t-Stat

p-value

−1.860 12.505

0.100 0.000

What is the regression equation?

A) Ŷ= 12.201 + 2.195X B) Ŷ = 2.195 − 12.201X C) Ŷ= 2.195 + 12.201X D) Ŷ= −12.201 + 2.195X

30) Which of the following is the same between a confidence interval and a prediction interval?

A) A confidence interval and prediction interval are the same width.

B) They both use the standard error of estimate.

C) They both provide a confidence interval for the mean.

D) The formulas are the same.

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31) A sales manager for an advertising agency believes there is a relationship between the number of contacts that a salesperson makes and the amount of sales dollars earned. A regression analysis shows the following results: Coefficients Intercept Number of contacts

Standard Error 6.560 0.176

−12.201 2.195

t-Stat

p-value

−1.860 12.505

0.100 0.000

What is the slope of the linear equation?

A) −12.201 B) 2.195 C) 12.505 D) −1.860

32)

Using the following information.

Coefficients

Intercept Independent variable

−12.8094 2.1794

ANOVA df

SS

Regression Residual

1 8

12,323.56 1,094.842

Total

9

13,418.4

MS 12,323.56 136.8553

F 90.0481

If testing the hypothesis H0: ρ = 0, the computed t-statistic is ________.

A) 9.49 B) 8.84 C) 8.18 D) Cannot be computed

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33) A sales manager for an advertising agency believes that there is a relationship between the number of contacts that a salesperson makes and the amount of sales dollars earned. A regression analysis shows the following results.

Coefficients Intercept Number of contacts

−12.201 2.195

Standard Error 6.560 0.176

t-Stat

p-value

−1.860 12.505

0.100 0.000

What is the Y-intercept of the linear equation?

A) −1.860 B) −12.201 C) 12.505 D) 2.195

34) Consider the following regression analysis between sales (Y in $1,000) and social media advertising (X in dollars). Ŷ = 55,000 + 7X The regression equation implies that an ________.

A) increase of $1 in advertising is associated with an increase of $7,000 in sales B) increase of $1 in advertising is associated with an increase of $7 in sales C) increase of $1 in advertising is associated with an increase of $62,000 in sales D) increase of $7 in advertising is associated with an increase of $7,000 in sales

35)

In the regression equation, what does the letter Y represent?

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A) The dependent variable B) The Y-intercept C) The independent variable D) The slope of the line

36)

An example of a way to rescale a variable to create a linear relationship is ________.

A) computing the log of all values of the dependent and independent variables B) adding the values of the dependent and independent variables to create a new dependent variable C) dividing all the values of the dependent variable by 5 D) adding 50 to all of the values of the dependent and independent variables

37) The regression equation is Ŷ = 30 + 2.59X, the sample size is 14, and the standard error of the slope is 0.98. What is the test statistic to test whether the slope is positive? Assume a level of significance of 0.01.

A) t = +2.643 B) z = −2.240 C) t = +2.685 D) z = +2.580

38) The coefficient of determination is the proportion of total variation in Y that is explained

by X. ⊚ true ⊚ false

39) Consider the following regression equation: Y = 30 + 8X. If SSE = 640 and SS Total = 1,600, then the correlation coefficient is _______.

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A) +0.775 B) −0.84 C) +0.84 D) −0.775

40)

Using the following information: Coefficients

Intercept Independent variable

−12.8094 2.1794

ANOVA df

SS

MS

F

Regression Residual

1 8

12,324.35 1,094.850

12,324.35 136.8641

90.0481

Total

9

13,419.2

What is the standard error of the estimate?

A) 136.8640 B) 11.6989 C) 1,094.850 D) 13,419.2

41)

The coefficient of determination is the square root of the coefficient of correlation. ⊚ true ⊚ false

42)

The standard error of estimate measures the accuracy of a prediction.

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⊚ ⊚

true false

43) The regression equation is Ŷ = 30 + 2.61X, the sample size is 31, and the standard error of the slope is 0.99. What is the critical value to test whether the slope is positive at the 0.01 significance level?

A) z = ±2.357 B) t = +2.462 C) z = +2.107 D) t = +2.836

44) An instructor is wondering if students who spend more time taking their final exam do better than those who take less time. The following data is gathered.

Minutes Score

57 96

47 92

36 92

83 77

86 96

117 96

87 81

62 85

87 88

86 96

68 70

106 81

95 77

72 74

95 77

If a student takes an hour to complete the exam, what would we expect them to score?

A) 60.0 B) 95.4 C) 86.2 D) 78.3

45)

A confidence interval can be determined for the mean value of Y for a given value of X. ⊚ true ⊚ false

46) An instructor is wondering if students who spend more time taking their final exam do better than those who take less time. The following data is gathered.

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Minutes Score

57 96

47 92

36 92

83 77

86 96

117 96

87 81

62 85

87 88

86 96

68 70

106 81

95 77

72 74

95 77

What is the correlation coefficient?

A) 0.651 B) −0.128 C) −0.053 D) 0.016

47) A sales manager for an advertising agency believes there is a relationship between the number of contacts that a salesperson makes and the amount of sales dollars earned. A regression analysis shows the following results.

Coefficients Intercept Number of contacts

−12.201 2.195

Standard Error 6.560 0.176

t-Stat

p-value

−1.860 12.505

0.100 0.000

What is the standard error of the slope?

A) −12.201 B) 0.176 C) 12.505 D) 6.560

48) The regression equation is Ŷ = 30 + 2.56X, the sample size is 14, and the standard error of the slope is 0.97. What is the critical value to test whether the slope is positive at the 0.01 significance level?

A) t = +2.681 B) z = ±2.576 C) z = +2.326 D) t = +3.055

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49)

What is the variable used to predict another variable called?

A) Independent variable B) Dependent variable C) Important variable D) Causal variable

50) An instructor is wondering if students who spend more time taking their final exam do better than those who take less time. The following data is gathered.

Minutes Score

57 96

47 92

36 92

83 77

86 96

117 96

87 81

62 85

87 88

86 96

68 70

106 81

95 77

72 74

95 77

What is the Y-intercept of the regressed line?

A) 89.38 B) −0.053 C) −0.128 D) 0.651

51)

Based on the regression equation, we can ________.

A) measure cause and effect B) predict the value of the independent variable given a value of the dependent variable C) measure the association between two variables D) predict the value of the dependent variable given a value of the independent variable

52)

What does a coefficient of correlation of 0.70 infer?

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A) There is almost no correlation because 0.70 is close to 1.0.

B) The coefficient of nondetermination is 0.30.

C) Seventy percent of the variation in one variable is explained by the other variable.

D) The coefficient of determination is 0.49.

53) An instructor is wondering if students who spend more time taking their final exam do better than those who take less time. The following data is gathered.

Minutes Score

57 96

47 92

36 92

83 77

86 96

117 96

87 81

62 85

87 88

86 96

68 70

106 81

95 77

72 74

What is the coefficient of determination?

A) −0.128 B) 0.016 C) 0.651 D) −0.053

54)

What is the general form of the regression equation?

A) Ŷ = ab B) Ŷ = (a + b)X C) Ŷ = abX D) Ŷ = a + (bX)

55)

A regression analysis yields the following information:

Compute the 95% confidence interval when X = 4.

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95 77

A) 0.0, 4.05 B) 4.12, 12.22 C) 2.67, 5.33 D) 6.84, 9.50

56)

Using the following information: Coefficients

Intercept Independent variable

−12.8094 2.1794

ANOVA df

SS

Regression Residual

1 8

12,323.56 1,094.842

Total

9

13,418.4

MS 12,323.56 136.8553

F 90.0481

What is the correlation coefficient?

A) 0.9184 B) 0.9004 C) −0.9583 D) 0.9583

57)

One assumption underlying linear regression is that the X values are normally distributed. ⊚ true ⊚ false

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58) The regression equation is Ŷ = 29.29 − 0.80X, the sample size is 21, and the standard error of the slope is 0.22. What is the critical value to test whether the slope is different from zero at the 0.01 significance level?

A) z = +1.480 B) t = ±2.861 C) z = ±1.730 D) t = +2.509

59) If all the plots on a scatter diagram lie on a straight line, what is the standard error of estimate?

A) −1 B) +1 C) Infinity D) 0

60) As the coefficient of determination is expressed as a percent, its value is between 0% and 100%. ⊚ true ⊚ false

61) A sales manager for an advertising agency believes that there is a relationship between the number of contacts that a salesperson makes and the amount of sales dollars earned. What is the independent variable?

A) Salesperson B) Amount of sales C) Sales manager D) Number of contacts

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62) If the correlation coefficient between two variables, X and Y, equals zero, what can be said of the variables X and Y? A) The variables are dependent on each other.

B) The variables are not linearly related.

C) X causes Y. D) The variables are highly linearly related.

63) A sales manager for an advertising agency believes there is a relationship between the number of contacts that a salesperson makes and the amount of sales dollars earned. A regression ANOVA shows the following results: ANOVA df

SS

MS

F

Significance F

Regression Residual

1.00 8.00

13,555.42 693.48

13,555.42 86.68

156.38

0.00

Total

9.00

14,248.90

What is the value of the standard error of estimate?

A) 86.68 B) 8.328 C) 9.310 D) 8.778

64) In regression, the difference between the confidence interval and prediction interval formulas is ________.

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A) the prediction interval uses r2 and the confidence interval uses r B) the addition of 1 to the quantity under the radical sign C) the prediction interval is the square root of the confidence interval D) no difference

65)

In the equation, Ŷ = a + bX, what is Ŷ?

A) It is the Y-intercept.

B) It is the predicted value of Y, given a specific X value.

C) It is the value of Y when X = 0.

D) It is the slope of the line.

66) An instructor is wondering if students who spend more time taking their final exam do better than those who take less time. The following data is gathered.

Minutes Score

57 96

47 92

36 92

83 77

86 96

117 96

87 81

62 85

87 88

86 96

68 70

106 81

95 77

72 74

95 77

What is the decision regarding the hypothesis that the slope is different from zero? Assume the level of significance is 0.05.

A) Fail to reject the alternative hypothesis. We conclude the correlation is not equal to zero.

B) Reject the null hypothesis. We conclude that the correlation is not equal to zero.

C) Reject the alternative hypothesis. We conclude that the correlation is equal to zero.

D) Fail to reject the null hypothesis. We conclude the correlation is equal to zero.

67)

What does the coefficient of determination equal if r = 0.89?

A) 0.9412 B) 0.7921 C) 0.1100 D) 0.0121

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68) What is the alternate hypothesis to test the significance of the slope in a regression equation?

A) H1: β ≥ 0 B) H1: β = 0 C) H1: β ≠ 0 D) H1: β ≤ 0

69) The regression equation is Ŷ = 29.29 − 0.96X, the sample size is 8, and the standard error of the slope is 0.22. What is the critical value to test whether the slope is different from zero at the 0.01 significance level?

A) t = +3.355 B) z = ±2.576 C) z = +2.326 D) t = ±3.707

70)

The values of a and b in the regression equation are called the regression coefficients. ⊚ true ⊚ false

71)

If r = 0.62, what does the coefficient of determination equal?

A) 0.7299 B) 0.3844 C) 0.1855 D) 0.5512

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72)

Using the following information: Coefficients

Intercept Independent variable

-12.8094 2.1794

ANOVA df

SS

Regression Residual

1 8

12,323.76 1,394.642

Total

9

13,718.4

MS 12,323.76 136.8550

F 90.0481

What is the correlation coefficient?

A) 0.8983 B) 0.9478 C) −0.9478 D) 0.8899

73)

Using the following information: Coefficients

Intercept Independent variable

−12.8094 2.1794

ANOVA df

SS

MS

F

Regression Residual

1 8

12,323.56 1,094.842

12,323.56 136.8553

90.0481

Total

9

13,418.4

What is the standard error of the estimate?

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A) 136.8552 B) 11.6985 C) 13,418.4 D) 1,094.842

74)

Which of the following are true assumptions underlying linear regression?

(1) For each value of X, there is a group of Y values that is normally distributed.

(2) The means of these normal distributions of Y values all lie on the regression line.

(3) The standard deviations of these normal distributions are equal.

A) Only (1) B) Only (3) C) All of these choices are correct.

D) Only (2)

75)

Using the following information: Coefficients

Intercept Independent variable

−12.8094 2.1794

ANOVA df

SS

Regression Residual

1 8

12,323.56 1,094.842

Total

9

13,418.4

MS 12,323.56 136.8553

F 90.0481

What is the coefficient of determination? Round the percentage to one decimal point.

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A) 91.8% B) 90.0% C) 8.2% D) 136.9%

76) An economist is interested in predicting the unemployment rate based on gross domestic product. As the economist is interested in predicting unemployment, the independent variable is gross domestic product. ⊚ true ⊚ false

77) If the correlation between two variables is close to one, the linear association between the variables is ________.

A) zero B) strong C) weak D) moderate

78)

The null hypothesis to test the slope of a regression equation is H0: α = 0. ⊚ true ⊚ false

79) Given the least squares regression equation, Ŷ = 1,232 + 1,163X, when X = 3, what does Ŷ equal?

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A) 5,884 B) 4,140 C) 8,180 D) 4,721

80) Consider the following regression equation: Y = 30 + 8X. If SSE = 720 and SS Total = 1,200, then the correlation coefficient is ________.

A) −0.632 B) −0.70 C) +0.632 D) +0.70

81) A sales manager for an advertising agency believes there is a relationship between the number of contacts that a salesperson makes and the amount of sales dollars earned. A regression ANOVA shows the following results: ANOVA df

SS

MS

F

Significance F

Regression Residual

1.00 8.00

13,555.42 693.48

13,555.42 86.68

156.38

0.00

Total

9.00

14,248.90

What is the value of the coefficient of correlation?

A) +0.6317 B) +0.9513 C) +0.9754 D) −0.9754

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82)

In the regression equation, what does the letter X represent?

A) The dependent variable B) The independent variable C) The Y-intercept D) The slope of the line

83) Correlation analysis is a statistical technique used to measure the strength of the relationship between two variables. ⊚ true ⊚ false

84) When comparing the 95% confidence and prediction intervals for a given regression analysis ________.

A) there is no difference between confidence and prediction intervals B) the confidence interval is wider than a prediction interval C) the confidence interval is narrower than a prediction interval D) the prediction interval has a higher level of confidence

85) An instructor is wondering if students who spend more time taking their final exam do better than those who take less time. The following data is gathered.

Minutes Score

57 96

47 92

36 92

83 77

86 96

117 96

87 81

62 85

87 88

86 96

68 70

106 81

95 77

72 74

What is the regressed linear relationship?

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95 77

A) Ŷ = 60.0 + 0.1276X B) Ŷ = 89.3767 − 0.0529X C) Ŷ = 9.6767 + 0.529X D) Ŷ = 100.00 − 0.529X

86)

What is the range of values for a coefficient of correlation?

A) 0 to +1.0 B) Unlimited range C) −1.0 to +1.0 inclusive D) −3 to +3 inclusive

87) Consider a regression analysis, where the correlation coefficient is 0.18. Then, the coefficient of determination is ________.

A) 0.3636 B) 0.4243 C) 0.0324 D) 1.1618

88) A hypothesis test is conducted at the 0.05 level of significance to test whether or not the population correlation is zero. If the sample consists of 25 observations and the correlation coefficient is 0.60, what conclusion should be drawn?

A) Fail to reject the null hypothesis.

B) Reject the null hypothesis and conclude the correlation in the population is not equal to zero.

C) Reject the null hypothesis and conclude the correlation in the sample is zero.

D) Fail to reject the null hypothesis and conclude the correlation in the population is zero.

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89)

Which value of r indicates a stronger correlation than +0.40?

A) −0.80 B) −0.30 C) 0 D) +0.38

90)

If r = 0.65, what does the coefficient of determination equal?

A) 0.5778 B) 0.1945 C) 0.4225 D) 0.8061

91) Given the least squares regression equation, Ŷ = 1,202 + 1,133X, when X = 3, what does Ŷ equal?

A) 4,050 B) 5,734 C) 8,000 D) 4,601

92) The regression equation is Ŷ = 29.29 − 0.96X, the sample size is 8, and the standard error of the slope is 0.22. We wish to test whether the slope in the population is different from zero using a level of significance of 0.01. What conclusion should be reached?

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A) Reject the null hypothesis and conclude the slope is equal to zero.

B) Fail to reject the null hypothesis and conclude the slope is equal to zero.

C) Fail to reject the null hypothesis.

D) Reject the null hypothesis and conclude the slope is not equal to zero.

93)

What does the coefficient of determination equal if r = 0.76?

A) 0.0937 B) 0.0101 C) 0.8034 D) 0.5776

94)

A regression analysis yields the following information:

Compute the 95% prediction interval when X = 4.

A) 6.84, 9.50 B) 2.67, 5.33 C) 0.0, 4.05 D) 4.12, 12.22

95) A sales manager for an advertising agency believes there is a relationship between the number of contacts that a salesperson makes and the amount of sales dollars earned. A regression analysis shows the following results.

Coefficients Intercept Number of contacts

−12.201 2.195

Standard Error 6.560 0.176

t-Stat

p-value

−1.860 12.505

0.100 0.000

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df

SS

MS

F

Significance F

Regression Residual

1.00 8.00

13,555.42 693.48

13,555.42 86.68

156.38

0.00

Total

9.00

14,248.90

Assume that and confidence interval for 30 calls is ________.

Rounding to one decimal place, the 95%

A) 31.1, 76.2 B) 51.4, 55.9 C) 55.8, 51.5 D) 46.7, 60.6

96) The regression equation is Ŷ = 30 + 2.56X, the sample size is 14, and the standard error of the slope is 0.97. If the significance level is 0.01, what conclusion should be reached about whether the slope is positive?

A) Reject the null hypothesis and conclude the slope is not equal to zero.

B) Fail to reject the null hypothesis.

C) Fail to reject the null hypothesis and conclude the slope less than zero.

D) Reject the null hypothesis and conclude the slope is greater than zero.

97) What is the chart called when the paired data (the dependent and independent variables) are plotted?

A) A histogram B) A pie chart C) A bar chart D) A scatter diagram

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98) A hypothesis test is conducted at the 0.05 level of significance to test whether or not the population correlation is zero. If the sample consists of 29 observations and the correlation coefficient is 0.60, what is the computed value of the test statistic? Round to two decimal places.

A) 2.37 B) 1.96 C) 3.90 D) 3.24

99) A sales manager for an advertising agency believes there is a relationship between the number of contacts that a salesperson makes and the amount of sales dollars earned. A regression ANOVA shows the following results: ANOVA df

SS

MS

F

Significance F

Regression Residual

1.00 8.00

13,555.42 693.48

13,555.42 87.08

156.38

0.00

Total

9.00

14,248.90

What is the value of the standard error of estimate?

A) 9.332 B) 87.08 C) 8.350 D) 8.800

100) A sales manager for an advertising agency believes there is a relationship between the number of contacts that a salesperson makes and the amount of sales dollars earned. A regression ANOVA shows the following results: ANOVA df

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SS

MS

F

Significance F

33

Regression Residual

1.00 8.00

13,594.42 654.72

Total

9.00

14,249.14

13,594.42 86.68

156.38

0.00

What is the value of the coefficient of determination?

A) 0.6347 B) −0.9541 C) 0.9541 D) 0.9768

101) A sales manager for an advertising agency believes there is a relationship between the number of contacts that a salesperson makes and the amount of sales dollars earned. A regression analysis shows the following results.

Coefficients Intercept Number of contacts

−12.201 2.195

Standard Error 6.560 0.176

t-Stat

p-value

−1.860 12.505

0.100 0.000

What is the decision regarding the hypothesisthat the slope is different from zero? Assume the level of significance is 0.05.

A) Fail to reject the null hypothesis. We conclude the slope is equal to zero.

B) Fail to reject the alternative hypothesis. We conclude the slope is not equal to zero.

C) Reject the alternative hypothesis. We conclude that the slope is equal to zero.

D) Reject the null hypothesis. We conclude that the slope is not equal to zero.

102) Assume the least squares equation is Ŷ = 10 + 20X. What does the value of 10 in the equation indicate?

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A) It is the error of estimation.

B) When X = 0, Y = 10.

C) X increases by 10 for each unit increase in Y. D) Y increases by 10 for each unit increase in X.

103)

In the regression equation, what does the letter b represent?

A) The Y-intercept B) The slope of the line C) Any value of the independent variable that is selected D) The value of Y when X = 0

104)

<p>In regression analysis, error is defined as ⊚ true ⊚ false

.

105)

Which of the following statements regarding the coefficient of correlation is true?

A) It is calculated as the square of the slope.

B) It ranges from 0.0 to +1.0 inclusive.

C) A value of 0.00 indicates two variables are related.

D) It describes the relationship between two variables.

106) The strength of the correlation between two variables depends on the sign of the coefficient of correlation. ⊚ true ⊚ false

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107)

In regression analysis, what is the predictor variable called?

A) Correlation variable B) Independent variable C) Dependent variable D) Variable of determination

108) An instructor is wondering if students who spend more time taking their final exam do better than those who take less time. The following data is gathered.

Minutes Score

57 96

47 92

36 92

83 77

86 96

117 96

87 81

62 85

87 88

86 96

68 70

106 81

95 77

72 74

What is the slope of the regressed line?

A) 0.651 B) −0.053 C) −0.128 D) 0.016

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95 77

Answer Key Test name: Chap 13_10e_Lind 1) TRUE 2) C 3) A 4) C 5) A 6) C 7) D 8) C 9) B 10) D 11) TRUE 12) A 13) D 14) C 15) A 16) A 17) TRUE 18) A 19) B 20) B 21) A 22) D 23) A 24) B 25) D 26) C Version 1

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27) C 28) A 29) D 30) B 31) B 32) A 33) B 34) A 35) A 36) A 37) A 38) TRUE 39) A 40) B 41) FALSE 42) TRUE 43) B 44) C 45) TRUE 46) B 47) B 48) A 49) A 50) A 51) D 52) D 53) B 54) D 55) D 56) D Version 1

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57) FALSE 58) B 59) D 60) TRUE 61) D 62) B 63) C 64) B 65) B 66) D 67) B 68) C 69) D 70) TRUE 71) B 72) B 73) B 74) C 75) A 76) TRUE 77) B 78) FALSE 79) D 80) C 81) C 82) B 83) TRUE 84) C 85) B 86) C Version 1

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87) C 88) B 89) A 90) C 91) D 92) D 93) D 94) D 95) D 96) B 97) D 98) C 99) A 100) C 101) D 102) B 103) B 104) FALSE 105) D 106) FALSE 107) B 108) B

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CHAPTER 14 1) The following correlations were computed as part of a multiple regression analysis that used education, job, and age to predict income.

Income

Education

Job

Income

1.000

Education

0.677

1.000

Job

0.173

−0.181

1.000

Age

0.369

0.073

0.689

Age

1.000

What is this table called?

A) Net regression coefficients B) Correlation matrix C) Coefficients of nondetermination D) Analysis of variance

2)

What does the correlation matrix for a multiple regression analysis contain?

A) The coefficients of multiple determination B) Simple correlation coefficients C) The variance inflation factors D) The multiple standard errors of estimate

3) In a multiple regression analysis, if the regression coefficient of a dummy variable is significant and has a sample coefficient value of 100, then the dummy variable's effect on the dependent variable is an increase of 100. ⊚ true ⊚ false

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4)

The degrees of freedom associated with the regression sum of squares equals ________.

A) (n − 2) B) 1 C) the F-ratio D) the number of independent variables

5) In an ANOVA table for a multiple regression analysis, the regression mean square is ________.

A) the total sum of squares divided by the regression degrees of freedom B) n − (k + 1) C) the regression sum of squares divided by the regression degrees of freedom D) the treatment sum of squares divided by the regression degrees of freedom

6) If a multiple regression analysis is based on 10 independent variables collected from a sample of 125 observations, what is the value of the denominator in the calculation of the multiple standard error of estimate?

A) 125 B) 10 C) 115 D) 114

7) The best example of an alternate hypothesis for a global test of a multiple regression model is ________.

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A) H1: β1 ≠ β2 ≠ β3 ≠ β4 ≠ 0 B) H1: β1 = β2 = β3 = β4 = 0 C) H1: Not all the βi's are equal to 0 D) if F is less than 20.00, then fail to reject

8) A manager at a local bank analyzed the relationship between monthly salary and three independent variables: Length of service (measured in months), Gender (0 = female, 1 = male), and Job type (0 = clerical, 1 = technical). The following ANOVA summarizes the regression results.

ANOVA Source of Variation Regression Residual

df

Sum of Squares

Mean Square

F

3 26

1,004,346.771 1,461,134.596

334,782.257 56,197.48445

5.96

Total

29

2,465,481.367

Intercept Service Gender Job

Coefficients

Standard Error

784.92 9.19 222.78 −28.21

322.25 3.20 89.00 89.61

t-Stat 2.44 2.87 2.50 −0.31

pvalue 0.02 0.01 0.02 0.76

The level of significance is 0.05. Based on the hypothesis tests for the individual regression coefficients, ________.

A) all the regression coefficients are not equal to zero B) "Service" is the only significant variable in the model C) "Job" is the only nonsignificant variable in the model D) the intercept is the only significant variable in the model

9) A correlation matrix can be used to assess multicollinearity between independent variables.

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⊚ ⊚

true false

10) In multiple regression analysis, an F-statistic is used to test the global hypothesis, H0: All βi = 0. ⊚ true ⊚ false

11) An instructor is wondering if students’ time on an exam, their sex, and their age can be used to predict their final score. The following data is gathered. (In the dummy variable sex, 0 = female, 1 = male) Score 96 92 77 96 96 81 85 88 96 70 81 77 74 77

Minutes 57 47 83 86 117 87 62 87 86 68 106 95 72 95

Sex 0 1 0 1 0 0 1 1 0 0 0 1 0 1

Age 34 40 27 30 32 38 36 28 23 55 48 49 40 38

What is the adjusted coefficient of determination considering all three independent variables?

A) 0.252 B) 7.625 C) 0.670 D) −0.128

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12) If the hypothesis H0: β1 = 0 is rejected, then the sample regression coefficient b1 indicates the change in the predicted value for a unit change in X1 when all other Xi variables are held constant. ⊚ true ⊚ false

13)

In multiple regression analysis, which is NOT an underlying assumption?

A) The residuals are normally distributed.

B) The variation of the residuals should exhibit a trend.

C) There is a linear relationship the dependent variable and each of the independent variables.

D) The independent variables should not be correlated.

14) The variance inflation factor (VIF) is used to select or remove independent variables to reduce the effects of multicollinearity in a multiple regression equation. ⊚ true ⊚ false

15) Stepwise regression analysis is a method that assists in selecting the most significant variables for a multiple regression equation. ⊚ true ⊚ false

16) A researcher is studying the effect of 10 different independent variables on a critical measure of business performance. A multiple regression analysis including all 10 variables is performed. What criterion could be used to eliminate 1 of the 10 variables?

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A) Largest p-value B) Multiple R2 C) Smallest regression coefficient D) Smallest p-value

17) If a multiple regression analysis is based on 10 independent variables collected from a sample of 141 observations, what is the value of the denominator in the calculation of the multiple standard error of estimate?

A) 130 B) 131 C) 10 D) 141

18) In multiple regression analysis, a residual is the difference between the value of an independent variable and its corresponding dependent-variable value. ⊚ true ⊚ false

19) When additional independent variables are added to a multiple regression model, ________.

A) the adjusted R2 will always increase B) the coefficient of multiple determination decreases C) R2 will always increase D) the independent variables will be correlated

20)

Which of the following statements about stepwise regression is true?

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A) It uses only dependent variables and adds them one by one.

B) It selects the independent variable with the weakest correlation first.

C) It is a step-by-step method that adds independent variables one by one in order to build a more efficient regression equation.

D) It uses independent variables with insignificant regression coefficients.

21) Twenty-one executives in a large corporation were randomly selected to study the effect of several factors on annual salary (expressed in $000s). The factors selected were age, seniority, years of college, number of company divisions to which they had been exposed, and the level of their responsibility. The results of the regression analysis follow.

Constant Std Error of the Estimate R2 n Degrees of Freedom

Regression Coefficients Coefficient Std Error

23.00371 2.91933 0.91404 21 15 Age

Seniority

−0.031

0.381

Years of College 1.452

0.183

0.158

0.387

# Divisions Level −0.089

3.554

0.541

0.833

Which one of the following is the dependent variable?

A) Annual salary B) Age C) Seniority D) Level of responsibility

22) The following correlations were computed as part of a multiple regression analysis that used education, job, and age to predict income.

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Income

Education

Job

Income

1.000

Education

0.677

1.000

Job

0.173

−0.181

1.000

Age

0.369

0.073

0.689

Age

1.000

Which is the dependent variable?

A) Age B) Education C) Income D) Job

23)

Which of the following is a characteristic of the F-distribution?

A) Equal to the t-distribution B) Positively skewed C) Normally distributed D) Negatively skewed

24) A manager at a local bank analyzed the relationship between monthly salary and three independent variables: Length of service (measured in months), Gender (0 = female, 1 = male), and Job type (0 = clerical, 1 = technical). The following ANOVA summarizes the regression results: ANOVA Source of Variation Regression Residual

df

Sum of Squares

Mean Square

F

3 26

1,004,346.771 1,461,134.596

334,782.257 56,197.48445

5.96

Total

29

2,465,481.367

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Intercept Service Gender Job

Coefficients

Standard Error

784.92 9.19 222.78 −28.21

322.25 3.20 89.00 89.61

t-Stat

pvalue 0.02 0.01 0.02 0.76

2.44 2.87 2.50 −0.31

Based on the ANOVA, the coefficient of multiple determination is ________.

A) cannot be computed B) 5.957% C) 59.3% D) 40.7%

25) If the coefficient of multiple determination is 0.81, what percent of variation is not explained?

A) 90% B) 19% C) 66% D) 81%

26) The following correlations were computed as part of a multiple regression analysis that used education, job, and age to predict income.

Income

Education

Job

Income

1.000

Education

0.677

1.000

Job

0.173

−0.181

1.000

Age

0.369

0.073

0.689

Age

1.000

Which independent variable has the weakest association with the dependent variable?

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A) Education B) Age C) Income D) Job

27)

When does multicollinearity occur in a multiple regression analysis?

A) When the dependent variables are highly correlated B) When the independent variables are highly correlated C) When the regression coefficients are correlated D) When the independent variables have no correlation

28) Consider the multiple regression model shown next between the dependent variable Y and four independent variables X1, X2, X3, and X4, which results in the following function: Ŷ = 33 + 8X1 − 6X2 + 16X3 + 18X4 For this model, there were 36 observations; SSR = 1,408 and SSE = 600.

The critical F-value at the 1% level of significance is A) 2.63 B) 3.99 C) 2.55 D) 3.85

29) In an ANOVA table for a multiple regression analysis, the global test of significance is based on the ________.

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A) regression mean square divided by the mean square error B) block and error variation C) treatment mean square divided by the error variation D) treatment mean square and block mean square

30)

What does the multiple standard error of estimate measure?

A) The change in Ŷ for a change in X1 B) The variability of the residuals C) The amount of explained variation D) The regression mean square error in the ANOVA table

31) The coefficient of multiple determination, R2, reports the proportion of the variation in Y that is not explained by the variation in the set of independent variables. ⊚ true ⊚ false

32) Consider the multiple regression model shown next between the dependent variable Y and four independent variables X1, X2, X3, and X4, which results in the following function: Ŷ = 33 + 8X1 − 6X2 + 16X3 + 18X4 For this model, there were 35 observations; SSR = 1,520 and SSE = 600. Assume a 0.01 significance level.

Based on the given information, which of the following conclusions is correct about the statistical significance of the overall model?

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A) Reject the null hypothesis that β3 = 0.

B) Reject the null hypothesis that β1 = β2 = β3 = β4 = 0.

C) Do not reject the null hypothesis that β1 = β2 = β3 = β4 = 0.

D) Reject the null hypothesis that β1 = 0.

33)

In multiple regression analysis, a dummy variable is ________.

A) an additional quantitative variable B) a new regression coefficient C) an ordinal variable with three or more values D) a nominal variable with only two values

34)

The coefficient of determination measures the proportion of ________.

A) variation due to regression B) variation due to the relationship among variables C) explained variation relative to total variation D) error variation relative to total variation

35)

What happens as the scatter of data values about the regression plane increases?

A) The error sum of squares decreases.

B) R2 increases.

C) (1 − R2) decreases.

D) The standard error of estimate increases.

36) A dummy is an independent variable that does not improve your multiple regression model.

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⊚ ⊚

true false

37) In a regression analysis, three independent variables are used in the equation based on a sample of 40 observations. In the ANOVA table for a multiple regression analysis, what are the degrees of freedom associated with the F-statistic?

A) 3 and 39 B) 2 and 39 C) 3 and 36 D) 4 and 40

38) A researcher is studying the relationship between 10 different variables and a critical measure of business performance. What method can be used to select the best set of variables to predict performance?

A) Stepwise regression B) Simple linear regression C) Residual analysis D) ANOVA

39) All other things being held constant, what is the change in the dependent variable for a unit change in X1 for the multiple regression equation: Ŷ = 5.2 + 6.3X1 − 7.1X2?

A) +4.4 B) +6.3 C) −7.1 D) +5.2

40)

A valid multiple regression analysis assumes or requires that ________.

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A) the observations are autocorrelated B) the independent variables and the dependent variable have a linear relationship C) the dependent variable is measured using an ordinal, interval, or ratio scale D) the residuals follow an F-distribution

41) Consider the multiple regression model shown next between the dependent variable Y and four independent variables X1, X2, X3, and X4, which results in the following function: Ŷ = 33 + 8X1 − 6X2 + 16X3 + 18X4 For this model, there were 35 observations; SSR = 1,400 and SSE = 600.

The critical F-value at the 1% level of significance is A) 4.02 B) 3.83 C) 2.61 D) 2.53

42) In a regression analysis, three independent variables are used in the equation based on a sample of 44 observations. In the ANOVA table for a multiple regression analysis, what are the degrees of freedom associated with the F-statistic?

A) 3 and 40 B) 3 and 43 C) 2 and 43 D) 4 and 44

43) In multiple regression analysis, testing the global null hypothesis that all regression coefficients are zero is based on ________.

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A) a z-statistic B) a binomial distribution C) a t-statistic D) an F-statistic

44) In an ANOVA table for a multiple regression analysis, total variation is separated into ________.

A) treatment and block variation B) treatment and error variation C) block and error variation D) regression and residual variation

45) Consider a regression model involving more than one independent variable. The test used to determine if the relationship between the dependent variable and the set of independent variables is significant is the ________.

A) t-test B) F-test C) z-test D) chi-square test

46)

In multiple regression analysis, residuals (Y − Ŷ) should be ________.

A) normally distributed with a mean of zero B) significantly different from zero C) qualitative variables D) correlated

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47) In multiple regression, a dummy variable is significantly related to the dependent variable when ________.

A) the dummy variable is coded as 2 or 3 B) the null hypothesis for the dummy variable’s regression coefficient is rejected C) the dummy variable is correlated with other independent variables D) the null hypothesis for the global test of the regression equation is rejected

48)

In multiple regression analysis, residuals (Y − Ŷ) are used to ________.

A) evaluate multicollinearity B) compare two regression coefficients C) provide a global test of a multiple regression model D) evaluate homoscedasticity

49) If the correlation between the two independent variables of a regression analysis is 0.11, and each independent variable separately is highly correlated to the dependent variable, what does this indicate?

A) Multicollinearity between these two independent variables.

B) An effective regression equation.

C) A negative relationship is not possible.

D) Only one of the two independent variables will explain a high percent of the variation.

50) In the general multiple regression equation, which of the following variables represents the Y-intercept?

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A) X1 B) Ŷ C) a D) b1

51) A manager at a local bank analyzed the relationship between monthly salary and three independent variables: Length of service (measured in months), Gender (0 = female, 1 = male), and Job type (0 = clerical, 1 = technical). The following ANOVA summarizes the regression results.

ANOVA Source of Variation Regression Residual

df

Sum of Squares

Mean Square

F

3 26

1,004,346.771 1,461,134.596

334,782.257 56,197.48445

5.96

Total

29

2,465,481.367

Intercept Service Gender Job

Coefficients

Standard Error

784.92 9.19 222.78 −28.21

322.25 3.20 89.00 89.61

t-Stat 2.44 2.87 2.50 −0.31

pvalue 0.02 0.01 0.02 0.76

The level of significance is 0.05. In the regression model, which of the following are dummy variables?

A) Gender and job B) Service and gender C) Intercept D) Service

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52) A manager at a local bank analyzed the relationship between monthly salary and three independent variables: Length of service (measured in months), Gender (0 = female, 1 = male), and Job type (0 = clerical, 1 = technical). The following ANOVA summarizes the regression results.

ANOVA Source of Variation Regression Residual

df

Sum of Squares

Mean Square

F

3 26

1,004,346.771 1,461,134.596

334,782.257 56,197.48445

5.96

Total

29

2,465,481.367

Coefficients Intercept Service Gender Job

784.92 9.19 222.78 −28.21

Standard Error 322.25 3.20 89.00 89.61

t-Stat 2.44 2.87 2.50 −0.31

pvalue 0.02 0.01 0.02 0.76

The level of significance is 0.05. The results for the variable gender show that ________.

A) gender is not related to monthly salary B) females average $222.78 more than males in monthly salary C) males average $222.78 more than females in monthly salary D) gender and length of service are correlated

53)

What can we conclude if the global test of regression rejects the null hypothesis?

A) Good predictions are not possible.

B) At least one of the regression coefficients is not equal to zero.

C) Strong correlations exist among the variables.

D) No relationship exists between the dependent variable and any of the independent variables.

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54) If there are four independent variables in a multiple regression equation, there are also four ________.

A) Y-intercepts B) dependent variables C) regression coefficients D) constant terms

55) In an ANOVA table, for a multiple regression analysis, the variation of the dependent variable explained by the variation of the independent variables is represented by ________.

A) the regression sum of squares B) the p-value C) the total sum of squares D) the residual mean square

56) Multiple regression analysis is used when one independent variable is used to predict values of two or more dependent variables. ⊚ true ⊚ false

57) Consider a multiple regression analysis involving 14 independent variables and 152 observations, with SSE = 408 and SS Total = 600. The coefficient of multiple determination is _______.

A) 0.30 B) 0.32 C) 0.59 D) 0.78

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58) An example of multicollinearity is that ABC Realty predicts the sale price of homes by using home square footage and bedrooms square footage as independent variables. ⊚ ⊚

true false

59) The best example of a null hypothesis for testing an individual regression coefficient is ________.

A) H0: β1 ≠ 0 B) H0: β1 = β2 = β3 = β4 = 0 C) H0: β1 = 0 D) H0: µ1 = µ2 = µ3 = µ4 = 0

60) In multiple regression analysis, when the independent variables are highly correlated, this situation is called ________.

A) autocorrelation B) homoscedasticity C) multicollinearity D) curvilinearity

61) An instructor is wondering if students’ time on an exam, their sex, and their age can be used to predict their final score. The following data is gathered. (In the dummy variable sex, 0 = female, 1 = male) Score 96 92 77 96 96 81 85

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Minutes 57 47 83 86 117 87 62

Sex 0 1 0 1 0 0 1

Age 34 40 27 30 32 38 36

20

88 96 70 81 77 74 77

87 86 68 106 95 72 95

1 0 0 0 1 0 1

28 23 55 48 49 40 38

Which variables, if any, should be included in the multiple regression model given a 5% level of significance test for the independent variables?

A) Minutes, Sex, and Age B) Only Age C) None of these variables are related to exam score.

D) Minutes and Sex

62) Consider the multiple regression model shown next between the dependent variable Y and four independent variables X1, X2, X3, and X4, which results in the following function: Ŷ = 33 + 8X1 − 6X2 + 16X3 + 18X4 For this model, there were 35 observations; SSR = 1,400 and SSE = 600. Assume a 0.01 significance level.

Based on the given information, which of the following conclusions is correct about the statistical significance of the overall model?

A) Reject the null hypothesis that β1 = β2 = β3 = β4 = 0.

B) Do not reject the null hypothesis that β1 = β2 = β3 = β4 = 0.

C) Reject the null hypothesis that β3 = 0.

D) Reject the null hypothesis that β1 = 0.

63) To evaluate the assumption of linearity, a multiple regression analysis should include ________.

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A) hypothesis tests of individual regression coefficients B) scatter diagrams of the dependent variable plotted as a function of each independent variable C) an ANOVA table D) a calculation of variance inflation factors

64)

Which statistic is used to test hypotheses about individual regression coefficients?

A) X2-statistic B) F-statistic C) t-statistic D) z-statistic

65) In multiple regression analysis, residual analysis is used to test the requirement that ________.

A) the prediction error is minimized B) the independent variables are the direct cause of the dependent variable C) the number of independent variables included in the analysis is correct D) the variation in the residuals is the same for all predicted values of Y

66)

An example of a dummy variable is "time to product’s first repair" in years. ⊚ true ⊚ false

67) A researcher is studying the effect of 10 different variables on a critical measure of business performance. In selecting the best set of independent variables to predict the dependent variable, the stepwise regression technique is used. How are variables selected for inclusion in the model?

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A) Smallest p-value B) Largest p-value C) Highest increase in the multiple R2 D) Smallest regression coefficient

68) A variable that can assume only one of two possible outcomes that take on the values of either 0 or 1, and is used to incorporate the effect of qualitative variables in a regression model, is referred to as ________.

A) an interaction B) a dummy variable C) a constant endogenous variable D) a constant

69)

Which statistic is used to test a global hypothesis about a multiple regression equation?

A) z-statistic B) F-statistic C) t-statistic D) X2-statistic

70) In multiple regression analysis, how is the degree of association between a set of independent variables and a dependent variable measured?

A) Confidence intervals B) Coefficient of multiple determination C) Autocorrelation D) Standard error of estimate

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71) Consider a multiple regression analysis involving 14 independent variables and 150 observations, with SSE = 180 and SS Total = 600. The coefficient of multiple determination is ________.

A) 0.40 B) 0.21 C) 0.30 D) 0.70

72)

The adjusted R2 accounts for the number of independent variables by ________.

A) adding one to the R2 B) using the degrees of freedom C) multiplying by the multiple standard error of the estimate D) using a subscript for R2

73) Multiple regression analysis is applied when analyzing the relationship between ________.

A) an independent variable and several dependent variables B) several regression equations and a single sample C) several dependent variables and several independent variables D) a dependent variable and several independent variables

74) A manager at a local bank analyzed the relationship between monthly salary and three independent variables: Length of service (measured in months), Gender (0 = female, 1 = male), and Job type (0 = clerical, 1 = technical). The following ANOVA summarizes the regression results.

ANOVA Source of Variation Regression

Version 1

df

Sum of Squares

Mean Square

F

3

1,004,346.771

334,782.257

5.96 24

Residual

26

1,461,134.596

Total

29

2,465,481.367

Intercept Service Gender Job

56,197.48445

Coefficients

Standard Error

784.92 9.19 222.78 −28.21

322.25 3.20 89.00 89.61

t-Stat 2.44 2.87 2.50 −0.31

pvalue 0.02 0.01 0.02 0.76

Based on the ANOVA and a 0.05 significance level, the global null hypothesis test of the multiple regression model ________.

A) will be rejected and conclude that monthly salary is related to at least one of the independent variables B) will be rejected and conclude that monthly salary is related to all of the independent variables C) will show a high multiple coefficient of determination D) will not be rejected

75) A manager at a local bank analyzed the relationship between monthly salary and three independent variables: Length of service (measured in months), Gender (0 = female, 1 = male), and Job type (0 = clerical, 1 = technical). The following ANOVA summarizes the regression results: ANOVA Source of Variation Regression Residual

df

Sum of Squares

Mean Square

F

3 26

1,034,356.839 1,431,124.528

334,782.257 56,197.48445

5.96

Total

29

2,465,481.367

Intercept Service Gender

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Coefficients

Standard Error

t-Stat

784.92 9.19 222.78

322.25 3.20 89.00

2.44 2.87 2.50

pvalue 0.02 0.01 0.02

25

Job

−28.21

89.61

−0.31

0.76

Based on the ANOVA, the coefficient of multiple determination is ________.

A) 42.0% B) 7.175% C) cannot be computed D) 60.6%

76)

When expressed as a percentage, what is the range of values for multiple R2?

A) −100% to +100% inclusive B) 0% to +100% inclusive C) −100% to 0% inclusive D) Unlimited range

77) If the correlation between the two independent variables of a regression analysis is 0.11 and each independent variable is highly correlated to the dependent variable, what does this indicate?

A) Two separate regression equations are required.

B) Only one of the independent variables should be used in the regression equation.

C) Both independent variables should be used to predict the dependent variable.

D) The independent variables are strongly related to each other.

78) The following correlations were computed as part of a multiple regression analysis that used education, job, and age to predict income.

Income Income

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Education

Job

Age

1.000

26

Education

0.677

1.000

Job

0.173

−0.181

1.000

Age

0.369

0.073

0.689

1.000

Which independent variable has the strongest association with the dependent variable?

A) Income B) Age C) Education D) Job

79)

A correlation matrix shows individual correlation coefficients for all pairs of variables. ⊚ true ⊚ false

80)

Stepwise regression analysis is also called a "backward elimination" method. ⊚ true ⊚ false

81)

The variance inflation factor can be used to reduce multicollinearity by ________.

A) eliminating correlated independent variables from a multiple regression model B) testing the null hypothesis that all regression coefficients equal zero C) decreasing homoscedasticity D) evaluating the distribution of residuals

82) For a global test of a multiple regression equation, the F-distribution is defined by the regression and residual degrees of freedom. ⊚ true ⊚ false Version 1

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83) A manager at a local bank analyzed the relationship between monthly salary and three independent variables: Length of service (measured in months), Gender (0 = female, 1 = male), and Job type (0 = clerical, 1 = technical). The following ANOVA summarizes the regression results.

ANOVA Source of Variation Regression Residual

df

Sum of Squares

Mean Square

F

3 26

1,004,346.771 1,461,134.596

334,782.257 56,197.48445

5.96

Total

29

2,465,481.367

Intercept Service Gender Job

Coefficients

Standard Error

784.92 9.19 222.78 −28.21

322.25 3.20 89.00 89.61

t-Stat 2.44 2.87 2.50 −0.31

pvalue 0.02 0.01 0.02 0.76

The level of significance is 0.05. Based on the hypothesis tests for the individual regression coefficients, ________.

A) all the regression coefficients are not equal to zero B) "Service" is the only significant variable in the model C) "Job" is the only significant variable in the model D) only months of service and gender are significantly related to monthly salary

84)

What can we conclude if the global test of regression does not reject the null hypothesis?

A) Good forecasts are possible.

B) The independent variables are good predictors.

C) A strong relationship exists among the variables.

D) No relationship exists between the dependent variable and any of the independent variables.

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85)

In multiple regression analysis, residuals (Y − Ŷ) are used to ________.

A) evaluate the assumption of linearity B) provide a global test of a multiple regression model C) compare two regression coefficients D) calculate the variance inflation factor

86) An instructor is wondering if students’ time on an exam, their sex, and their age can be used to predict their final score. The following data is gathered. (In the dummy variable sex, 0 = female, 1 = male) Score 96 92 77 96 96 81 85 88 96 70 81 77 74 77

Minutes 57 47 83 86 117 87 62 87 86 68 106 95 72 95

Sex 0 1 0 1 0 0 1 1 0 0 0 1 0 1

Age 34 40 27 30 32 38 36 28 23 55 48 49 40 38

What is the multiple standard error of the estimate?

A) 7.995 B) 12.256 C) 4.246 D) 6.703

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87) In multiple regression analysis, before testing the significance of the individual regression coefficients, ________.

A) the multiple standard error of the estimate must be less than the error mean square B) the intercept must equal 0 C) the null hypothesis that all regression coefficients equal zero must be rejected D) the null hypothesis that all regression coefficients equal zero must not be rejected

88) The best example of a null hypothesis for a global test of a multiple regression model is ________.

A) H0: β1 = β2 = β3 = β4 = 0 B) H0: β1 = 0 C) H0: µ1 = µ2 = µ3 = µ4 = 0 D) if F is greater than 20.00, then reject

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Answer Key Test name: Chap 14_10e_Lind 1) B 2) B 3) TRUE 4) D 5) C 6) D 7) C 8) C 9) TRUE 10) TRUE 11) A 12) TRUE 13) B 14) TRUE 15) TRUE 16) A 17) A 18) FALSE 19) C 20) C 21) A 22) C 23) B 24) D 25) B 26) D Version 1

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27) B 28) B 29) A 30) B 31) FALSE 32) B 33) D 34) C 35) D 36) FALSE 37) C 38) A 39) B 40) B 41) A 42) A 43) D 44) D 45) B 46) A 47) B 48) D 49) B 50) C 51) A 52) C 53) B 54) C 55) A 56) FALSE Version 1

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57) B 58) TRUE 59) C 60) C 61) B 62) A 63) B 64) C 65) D 66) FALSE 67) C 68) B 69) B 70) B 71) D 72) B 73) D 74) A 75) A 76) B 77) C 78) C 79) TRUE 80) FALSE 81) A 82) TRUE 83) D 84) D 85) A 86) A Version 1

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87) C 88) A

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CHAPTER 15 1)

Which of the following statements is correct regarding the chi-square distribution?

A) The shape of the distribution is based on the degrees of freedom.

B) The variance of the distribution is equal to one.

C) The distribution is negatively skewed.

D) Chi-square is based on two sets of degrees of freedom, one for the numerator and one for the denominator.

2) Based on the Nielsen ratings, the local CBS affiliate claims its 11 p.m. newscast reaches 61% of the viewing audience in the area. In a survey of 100 viewers, 56% indicated that they watch the late evening news on this local CBS station. What is the test statistic?

A) −1.03 B) 1.23 C) 1.03 D) −1.23

3) It is claimed that in a bushel of peaches, fewer than 10% are defective. A sample of 400 peaches is examined and 50 are found to be defective. What is the critical value for α = 0.025?

A) +2.326 B) −1.645 C) ±1.645 D) −1.960

4) Based on the Nielsen ratings, the local CBS affiliate claims its 11 p.m. newscast reaches 41% of the viewing audience in the area. In a survey of 100 viewers, 36% indicated that they watch the late evening news on this local CBS station. What is the null hypothesis?

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A) H0: π ≠ 0.36 B) H0: π = 0.36 C) H0: π = 0.41 D) H0: µ = 0.41

5) A survey of property owners' opinions about a street-widening project was taken to determine if owners' opinions were related to the distance between their home and the street.The level of significance for this study is 0.10. A randomly selected sample of 100 property owners was contacted and the results are shown next.

Front Footage

Opinion Undecided 4 5 2

For 12 35 3

Under 45 feet 45–120 feet Over 120 feet

Against 4 30 5

What is the critical value?

A) 10.645 B) 7.779 C) 9.488 D) 13.362

6) The following table classifies 100 individuals using two variables, Gender and College attended.

None

College Attended Two-year Four-year

Total

Gender Male Female Total

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7 13 20

13 17 30

30 20 50

50 50 100

2

What is this two-way classification called?

A) Contingency table B) Frequency table C) Goodness-of-fit test D) ANOVA table

7) It is claimed that in a bushel of peaches, fewer than 10% are defective. A sample of 400 peaches is examined and 50 are found to be defective. If α = 0.025, what is the p-value?

A) 0.9525 B) 0.4525 C) 0.0475 D) 0.5475

8) It is claimed that in a bushel of peaches, fewer than 10% are defective. A sample of 400 peaches is examined and 54 are found to be defective. What is the z-test statistic?

A) +2.333 B) −2.311 C) +0.288 D) +0.135

9)

The chi-square statistic has _______.

A) a family of distributions B) one distribution C) two distributions D) a uniform distribution

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10) A personnel manager is concerned about absenteeism. She decides to sample employee records to determine if absenteeism is distributed evenly throughout the six-day workweek. The null hypothesis is: Absenteeism is distributed evenly throughout the week.Use the 0.01 level of significance. The sample results are: Day of the Week Monday Tuesday Wednesday Thursday Friday Saturday

Number of Employees Absent 10 9 12 10 9 10

What is the calculated value of chi-square?

A) 0.6 B) 6.0 C) .8 D) 0.5

11) Based on the Nielsen ratings, the local CBS affiliate claims its 11 p.m. newscast reaches 41% of the viewing audience in the area. In a survey of 100 viewers, 36% indicated that they watch the late evening news on this local CBS station. What is the test statistic?

A) 1.22 B) 1.02 C) −1.22 D) −1.02

12) In a goodness-of-fit test, the null hypothesis (no difference between sets of observed and expected frequencies) is rejected when the _______.

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A) difference between the observed and expected frequencies is small B) difference between the observed and expected frequencies is significantly large C) computed chi-square is less than the critical value D) difference between the observed and expected frequencies occurs by chance

13) A personnel manager is concerned about absenteeism. She decides to sample employee records to determine if absenteeism is distributed evenly throughout the six-day workweek. The null hypothesis is: Absenteeism is distributed evenly throughout the week. Use the 0.01 level of significance. The sample results are: Day of the Week Monday Tuesday Wednesday Thursday Friday Saturday

Number of Employees Absent 12 9 11 10 9 9

What is the p-value?

A) 5.0% B) 15.1% C) 48.9% D) 97.7%

14) A personnel manager is concerned about absenteeism. She decides to sample employee records to determine if absenteeism is distributed evenly throughout the six-day workweek. The null hypothesis is: Absenteeism is distributed evenly throughout the week. Use the 0.01 level of significance. The sample results are: Day of the Week Monday Tuesday Wednesday Thursday

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Number of Employees Absent 12 9 11 10 5

Friday Saturday

9 9

How many degrees of freedom are there?

A) 5 B) 3 C) 0 D) 4

15)

The chi-square distribution is positively skewed. ⊚ true ⊚ false

16) In testing the difference between two population proportions, we pool the two sample proportions to estimate the population proportion. ⊚ true ⊚ false

17) Recently, students in a marketing research class were interested in the driving behavior of students. Specifically, the marketing students were interested in finding out if exceeding the speed limit was related to gender.The study will use 0.05 as the significance level. They collected the following responses from 100 randomly selected students.

Male Female

Exceeds the Speed Limit

Does Not Exceed the Speed Limit

40 10

25 25

What is the critical value for the test statistic?

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A) 3.841 B) 5.991 C) 9.488 D) 7.815

18) A sample of 250 adults(A) tried the new multigrain cereal Wow! A total of 187 rated it as excellent. In a sample of 100 children (C), 66 rated it as excellent. Using the 0.1 significance level, the researcher wishes to show that adults like the cereal better than children. Which of the following is the alternate hypothesis?

A) H1: πA > πC B) H1: πA < πC C) H1: πA = πC D) H1: πA≠ πC

19) Based on the Nielsen ratings, the local CBS affiliate claims its 11 p.m. newscast reaches 41% of the viewing audience in the area. In a survey of 100 viewers, 36% indicated that they watch the late evening news on this local CBS station. What is the sample proportion?

A) 0.36 B) 0.41 C) 0.36% D) 0.41%

20) Recently, students in a marketing research class were interested in the driving behavior of students. Specifically, the marketing students were interested in finding out if exceeding the speed limit was related to gender. The study will use 0.05 as the significance level. They collected the following responses from 100 randomly selected students.

Male

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Exceeds the Speed Limit

Does Not Exceed the Speed Limit

40

25 7

Female

10

25

The null hypothesis for the analysis is _______.

A) a relationship between gender and speeding exists B) the correlation between driving behavior and gender is zero C) the mean of driving behavior equals the mean of gender D) there is no relationship between gender and speeding

21) If 20 out of 50 students sampled live in a college dormitory, what is the estimated proportion of students at the university living in a dormitory?

A) 0.50 B) 0.20 C) 0.40 D) 0.60

22) In a market test of a new chocolate raspberry coffee, a poll of 400 people from Dobbs Ferry showed 250 preferred the new coffee. In Irvington, 170 out of 350 people preferred the new coffee. To test the hypothesis that there is no difference in preferences between the two villages, what is the null hypothesis?

A) H0: π1 = π2 B) H0: π1≠ π2 C) H0: π1 > π2 D) H0: π1 < π2

23) For people released from prison, the following table shows their adjustment to civilian life and place of residence.

Adjustment to Civilian Life Outstanding Good Fair Unsatisfactory

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Residence after prison Hometown Not hometown Total

27 13 40

35 15 50

33 27 60

25 25 50

What is the critical value for this contingency table at the 0.01 level of significance?

A) 11.345 B) 13.277 C) 2.070 D) 9.488

24) A survey of property owners' opinions about a street-widening project was taken to determine if owners' opinions were related to the distance between their home and the street.The level of significance for this study is 0.05. A randomly selected sample of 100 property owners was contacted and the results are shown next.

Front Footage Under 45 feet 45–120 feet Over 120 feet

For 12 35 3

Opinion Undecided 4 5 2

Against 4 30 5

What is the expected frequency for people against the project and who have over 120 feet of property foot frontage?

A) 1.1 B) 5.5 C) 5.0 D) 3.9

25) The degrees of freedom for a contingency table with six rows and three columns is _______.

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A) 3 B) 10 C) 18 D) 9

26) Students were sampled to determine their support for the legalization of gambling in their community. A sample of 150 students were asked whether or not they supported legalization of gambling, and the following results were obtained. Use a 5% level-of-significance.

Do You Support Legal Gambling?

Yes, support No, don't support No opinion

Number of Students 40 60 50

For a goodness-of-fit test that the category frequencies are the same, what decision should be made regarding the null hypothesis.

A) Reserve judgment until a larger sample can be taken.

B) Reject the null hypothesis. The frequencies are different.

C) Reject the alternate hypothesis. The frequencies are the same.

D) Do not reject the null hypothesis. The frequencies are the same.

27) A recent study of the relationship between social activity and education for a sample of corporate executives showed the following results.

Education College High school Grade school

Above Average 30 20 10

Social Activity Average Below Average 20 10 40 90 50 130

Based on the analysis and a level of significance of 0.05, what can be concluded?

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A) Social activity and education are related.

B) No conclusion is possible.

C) Social activity and education are correlated.

D) Social activity and education are not related.

28) What is the critical value at the 0.05 level of significance for a goodness-of-fit test if there are six categories?

A) 5.991 B) 11.070 C) 3.841 D) 7.815

29)

The chi-square statistic _______.

A) is equal to zero B) is less than or equal to zero C) is greater than or equal to zero D) can be any value

30) A recent study of the relationship between social activity and education for a sample of corporate executives showed the following results.

Education College High school Grade school

Above Average 30 20 10

Social Activity Average Below Average 20 10 40 90 50 130

The degrees of freedom for the analysis are _______.

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A) 2 B) 4 C) 8 D) 6

31) In contingency table analysis, the expected frequency for a cell is found by dividing the row total by the grand total. ⊚ true ⊚ false

32) It is claimed that in a bushel of peaches,less than 10% are defective. A sample of 400 peaches is examined and 50 are found to be defective. What is the null hypothesis?

A) H0: π≠ 0.10 B) H0: π≥ 0.10 C) H0: π ≤ 0.10 D) H0: π < 0.10

33) To test the hypothesis that 55% of those families who plan to purchase a vacation residence in Florida want a condominium, the null hypothesis is π = 0.55 and the alternate is π ≠ 0.55. A random sample of 400 families who planned to buy a vacation residence revealed that 228 families want a condominium. What decision should be made regarding the null hypothesis using the 0.01 level of significance?

A) Purchase a condominium.

B) Cannot accept it or reject it based on the information given.

C) Do not reject it.

D) Reject it.

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34) A sample of 270 adults(A) tried the new multigrain cereal Wow! A total of 207 rated it as excellent. In a sample of 102 children (C), 76 rated it as excellent. Using the 0.1 significance level, the researcher wishes to show that adults like the cereal better than children. What is the pooled proportion?

A) 0.532 B) 0.761 C) 0.845 D) 1.446

35) If the decision is to reject the null hypothesis of no difference between two population proportions at the 5% level of significance, whatis the alternative hypothesis andthe rejection region?

A) H1: π1 > π2; z < −1.645 B) H1: π1 ≠ π2; z > +1.645 and z < −1.645 C) H1: π1 > π2; z < −1.960 D) H1: π1 ≠ π2; z > +1.960 and z < −1.960

36)

The chi-square test statistic used in a goodness-of-fit test has k − 1 degrees of freedom. ⊚ true ⊚ false

37) The claim that "male and female students at Coastal Carolina University prefer different parking lots on campus" is an example of a chi-square null hypothesis. ⊚ true ⊚ false

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38) In a market test of a new chocolate raspberry coffee, a poll of 400 people (Sample 1) from Dobbs Ferry showed 250 preferred the new coffee. In Irvington, 170 out of 350 people (Sample 2) preferred the new coffee. To test the hypothesis that a higher proportion of people in Dobbs Ferry prefer the new coffee, what is the alternate hypothesis?

A) H1: π1 = π2 B) H1: π1≠ π2 C) H1: π1 < π2 D) H1: π1 > π2

39) It is claimed that in a bushel of peaches, fewer than 10% are defective. A sample of 400 peaches is examined and 50 are found to be defective. What is the sample proportion?

A) 40 B) 0.40 C) 0.125 D) 0.10

40) Tests of hypothesis for a single population proportion use the normal distribution if the binomial assumptions are met and when both nπ and n(1 − π) are greater than or equal to five. ⊚ true ⊚ false

41) A personnel manager is concerned about absenteeism. She decides to sample employee records to determine if absenteeism is distributed evenly throughout the six-day workweek. The null hypothesis is: Absenteeism is distributed evenly throughout the week. The 0.01 level is to be used. The sample results are: Day of the Week Monday Tuesday Wednesday Thursday

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Number of Employees Absent 12 9 11 10 14

Friday Saturday

9 9

What is the critical value of a chi-square?

A) 15.033 B) 15.086 C) 16.812 D) 13.388

42) A sample of 250 adults(A) tried the new multigrain cereal Wow! A total of 187 rated it as excellent. In a sample of 100 children (C), 66 rated it as excellent. Using the 0.1 significance level, the researcher wishes to show that adults like the cereal better than children. What is the pooled proportion?

A) 1.408 B) 0.807 C) 0.723 D) 0.494

43)

For a goodness-of-fit test, the following are possible null and alternate hypotheses:

H0: Sales areequally distributed among the five locations.

H1: Sales are notequally distributed among the five locations. ⊚ true ⊚ false

44) One hundred voters in a particular county were sampled to determine their support for three mutually exclusive state ballot initiatives in the upcoming election. The following table presents the frequency of county voters in favor of each initiative (f0) compared to the expected number of voters in favor (fe) based on a statewide survey results.

Ballot Initiative

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fe

15

A B C

65 20 15

70 10 20

The polling group wishes to conduct chi-square analysis to determine whether the county support for each initiative differs from that of the state overall. Which of the following statements is true?

A) Chi-square analysis is appropriate in this case because none of the categories have expected frequencies less than five.

B) We must determine whether the data is normally distributed before we can use chisquare analysis.

C) Chi-square analysis cannot be used because the expected frequencies are not equal for each ballot initiative.

D) Ballot initiatives B and C should be combined as the expected frequencies are too low.

45) In the goodness-of-fit test, the chi-square distribution is used to determine how well an observed distribution of observations "fits" an expected distribution of observations. ⊚ true ⊚ false

46)

How is a pooled estimate of the population proportion represented?

A) z B) pc C) nπ D) π

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47) Recently, students in a marketing research class were interested in the driving behavior of students. Specifically, the marketing students were interested in finding out if exceeding the speed limit was related to gender.The study will use 0.05 as the significance level. They collected the following responses from 100 randomly selected students.

Exceeds the Speed Limit

Does Not Exceed the Speed Limit

40 10

25 25

Male Female

Based on the analysis, what can be concluded?

A) Driving behavior and gender are not related.

B) Driving behavior and gender are correlated.

C) No conclusion is possible.

D) Driving behavior and gender are related.

48) A recent study of the relationship between social activity and education for a sample of corporate executives showed the following results.

Education College High school Grade school

Above Average 30 20 10

Social Activity Average Below Average 20 10 40 90 50 130

The null hypothesis for the analysis is _______.

A) the correlation between social activity and education is zero B) the mean of social activity equals the mean of education C) there is no relationship between social activity and education D) as social activity increases, education increases

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49) Based on the Nielsen ratings, the local CBS affiliate claims its 11 p.m. newscast reaches 41% of the viewing audience in the area. In a survey of 100 viewers, 36% indicated that they watch the late evening news on this local CBS station. What is(are) the critical value(s) if the level of significance is 0.10?

A) ±1.282 B) −2.576 C) ±1.645 D) ±2.576

50) A distributor of personal computers has five locations in a city. In the year's first quarter, the sales in units were: Location North side Pleasant township Southwick I-90 Venice avenue Total

Observed Sales (units) 70 75 70 50 35 300

Perform a goodness-of-fit test that sales were the same for all locations. What decision should be made regarding the null hypothesis using the 0.01 level of significance?

A) Do not reject the null hypothesis. The frequencies are the same.

B) Reserve judgment until a larger sample can be taken.

C) Reject the alternate hypothesis. The frequencies are the same.

D) Reject the null hypothesis. The frequencies are different.

51) A sample of 250 adults tried the new multigrain cereal Wow! A total of 187 rated it as excellent. In a sample of 100 children, 66 rated it as excellent. Using the 0.1 significance level, the researcher wishes to show that adults like the cereal better than children. What test statistic should we use to compare the ratings of adults and children?

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A) A z-statistic B) A right one-tailed test statistic C) A t-statistic D) A left one-tailed test statistic

52)

The sample proportion is defined as _______.

A) nπ B) π C) x / n D) n!

53) It is claimed that in a bushel of peaches, fewer than 10% are defective. A sample of 400 peaches is examined and 70 are found to be defective. What is the sample proportion?

A) 40 B) 0.40 C) 0.175 D) 0.10

54) A recent study of the relationship between social activity and education for a sample of corporate executives showed the following results. Use 0.05 as the level of significance.

Education College High school Grade school

Above Average 30 20 10

Social Activity Average Below Average 20 10 40 90 50 130

What is the critical value for the test statistic?

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A) 3.841 B) 9.488 C) 7.815 D) 5.991

55) The computed chi-square value is positive because the difference between the observed and expected frequencies is _______.

A) uniform B) squared C) linear D) always positive

56) Students were sampled to determine their support for the legalization of gambling in their community. A sample of 150 students were asked whether or not they supported legalization of gambling, and the following results were obtained.

Do You Support Legal Gambling?

Yes, support No, don't support No opinion

Number of Students 40 60 50

The number of degrees of freedom associated with this scenario is _______.

A) 149 B) 2 C) 150 D) 3

57) Three new colors have been proposed for the Jeep Grand Cherokee vehicle. They are silver blue, almond, and willow green. The null hypothesis for a goodness-of-fit test would be _______.

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A) willow green is preferred over the other colors B) it is impossible to determine C) any one color is preferred over the other colors D) there is no preference between the colors

58) A personnel manager is concerned about absenteeism. She decides to sample employee records to determine if absenteeism is distributed evenly throughout the six-day workweek. The null hypothesis is: Absenteeism is distributed evenly throughout the week. The 0.01 level is to be used. The sample results are: Day of the Week Monday Tuesday Wednesday Thursday Friday Saturday

Number of Employees Absent 12 9 11 10 9 9

What kind of frequencies are the numbers 12, 9, 11, 10, 9, and 9 called?

A) Expected frequencies B) Observed frequencies C) Critical frequencies D) Acceptance frequencies

59) When determining how well an observed set of frequencies fits an expected set of frequencies, what is the test statistic?

A) z-statistic B) X2-statistic C) F-statistic D) t-statistic

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60)

The chi-square distribution becomes more symmetrical as the _______.

A) number of variables increases B) chi-square value increases C) degrees of freedom increase D) degrees of freedom decrease

61) test.

The use of the chi-square statistic would be permissible in the following goodness-of-fit

Literate Illiterate

⊚ ⊚

Observed Frequency

Expected Frequency

639 6

642 3

true false

62) It is claimed that in a bushel of peaches, fewer than 10% are defective. A sample of 400 peaches is examined and 50 are found to be defective. What is the alternate hypothesis for a onetailed test?

A) H1: π< 0.10 B) H1: π ≥ 0.10 C) H1: π> 0.10 D) H1: π≤ 0.10

63) A personnel manager is concerned about absenteeism. She decides to sample employee records to determine if absenteeism is distributed evenly throughout the six-day workweek. The null hypothesis is: Absenteeism is distributed evenly throughout the week.Use the 0.01 level of significance. The sample results are:

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Day of the Week Monday Tuesday Wednesday Thursday Friday Saturday

Number of Employees Absent 26 23 25 24 23 23

What is the expected frequency for Wednesday?

A) 24 B) 25 C) 26 D) 23

64) A recent study of the relationship between social activity and education for a sample of corporate executives showed the following results.

Education College High school Grade school

Above Average 30 20 10

Social Activity Average Below Average 20 10 40 90 50 130

The appropriate test to analyze the relationship between social activity and education is _______.

A) a regression analysis B) a contingency table analysis C) an analysis of variance D) a goodness-of-fit test

65) It is claimed that in a bushel of peaches, fewer than 10% are defective. A sample of 400 peaches is examined and 50 are found to be defective. What is the z-test statistic?

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A) −1.645 B) +0.125 C) +0.278 D) +1.667

66) The number of trials and the population proportion are respectively represented by what symbols?

A) p and n B) z and t C) α and β D) n and π

67) What is the decision regarding the differences between the observed and expected frequencies if the critical value of the chi-square is 9.488 and the computed chi-square value is 6.079?

A) Fail to reject the alternate hypothesis.

B) More information is needed to answer this question.

C) Fail to reject the null hypothesis; the difference is probably due to sampling error.

D) Reject the null hypothesis.

68) Suppose we test H0: π1 = π2 at the 0.05 level of significance. If the z-test statistic is −1.07, what is our decision?

A) Reject the alternate hypothesis.

B) Reserve judgment until a larger sample can be taken.

C) Do not reject the null hypothesis.

D) Reject the null hypothesis.

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69) Which of the following can be used to test the hypothesis that two nominal variables are related?

A) A contingency table analysis B) A goodness-of-fit test C) A regression analysis D) ANOVA table

70)

The shape of the chi-square distribution depends on the size of the sample. ⊚ true ⊚ false

71) Based on the Nielsen ratings, the local CBS affiliate claims its 11 p.m. newscast reaches 54% of the viewing audience in the area. In a survey of 100 viewers, 49% indicated that they watch the late evening news on this local CBS station. What is the sample proportion?

A) 0.54 B) 0.49% C) 0.49 D) 0.54%

72) What is our decision for a goodness-of-fit test with a computed chi-square value of 1.273 and a critical value of 13.388?

A) Do not reject the null hypothesis.

B) We should take a larger sample.

C) We are unable to reject or not reject the null hypothesis based on data.

D) Reject the null hypothesis.

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73) Nonparametric tests require no assumptions about the shape of the population distribution. ⊚ true ⊚ false

74)

Which chi-square distribution would be closest to a normal distribution?

A) The distribution with 12 degrees of freedom B) The distribution with 15 degrees of freedom C) The distribution with 9 degrees of freedom D) The distribution with 3 degrees of freedom

75) A survey of property owners' opinions about a street-widening project was taken to determine if owners' opinions were related to the distance between their home and the street.The level of significance for this study is 0.05. A randomly selected sample of 100 property owners was contacted and the results are shown next.

Front Footage Under 45 feet 45–120 feet Over 120 feet

For 12 35 3

Opinion Undecided 4 5 2

Against 4 30 5

How many degrees of freedom are there?

A) 8 B) 6 C) 2 D) 4

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76) The pooled estimate of the proportion is found by dividing the total number of samples by the total number of successes. ⊚ true ⊚ false

77) Based on the Nielsen ratings, the local CBS affiliate claims its 11 p.m. newscast reaches 41% of the viewing audience in the area. In a survey of 100 viewers, 36% indicated that they watch the late evening news on this local CBS station. What is your decision if α = 0.01?

A) Fail to reject the null hypothesis.

B) Reject the alternate and conclude the newscast reaches about 41% of the audience.

C) Reject the null hypothesis and conclude the newscast does not reach 41% of the audience.

D) Fail to reject the alternate and conclude the newscast does not reach 41% of the audience.

78) For a chi-square test involving a contingency table, suppose the null hypothesis is rejected. We conclude that the two variables are _______.

A) curvilinear B) related C) linear D) not related

79) Based on the Nielsen ratings, the local CBS affiliate claims its 11 p.m. newscast reaches 41% of the viewing audience in the area. In a survey of 100 viewers, 36% indicated that they watch the late evening news on this local CBS station. What is the p-value for this test?

A) 0.3416 B) 0.3078 C) 0.6832 D) 0.1539

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80) The contingency table for a sample of corporate executives classified by educational level and social activity follows: Education College High school Grade school

Above Average 16 6 66

Social Activity Average 20 124 8

Below Average 10 90 60

What does the expected frequency for the "Above Average" social activity and "High school" education equal?

A) 48.40 B) 54.40 C) 85.90 D) 35.40

81) A personnel manager is concerned about absenteeism. She decides to sample employee records to determine if absenteeism is distributed evenly throughout the six-day workweek. The null hypothesis is: Absenteeism is distributed evenly throughout the week.Use the 0.01 level of significance. The sample results are: Day of the Week Monday Tuesday Wednesday Thursday Friday Saturday

Number of Employees Absent 12 9 11 10 9 9

What is the calculated value of chi-square?

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A) 0.5 B) 0.8 C) 8.0 D) 1.0

82) A survey of property owners' opinions about a street-widening project was taken to determine if owners' opinions were related to the distance between their home and the street.The level of significance for this study is 0.05. A randomly selected sample of 100 property owners was contacted and the results are shown next.

Front Footage For 12 35 3

Under 45 feet 45–120 feet Over 120 feet

Opinion Undecided 4 5 2

Against 4 30 5

What is the expected frequency for people who are undecided about the project and have property front footage between 45 and 120 feet?

A) 7.7 B) 2.2 C) 5.0 D) 3.9

83) Recently, students in a marketing research class were interested in the driving behavior of students. Specifically, the marketing students were interested in finding out if exceeding the speed limit was related to gender.The study will use 0.05 as the significance level. They collected the following responses from 100 randomly selected students.

Male Female

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Exceeds the Speed Limit

Does Not Exceed the Speed Limit

40 10

25 25

29

The degrees of freedom for the analysis are _______.

A) 3 B) 2 C) 4 D) 1

84) Students were sampled to determine their support for the legalization of gambling in their community. A sample of 150 students were asked whether or not they supported legalization of gambling, and the following results were obtained: Do You Support Legal Gambling?

Yes, support No, don't support No opinion

Number of Students 48 60 42

The value of the chi-square test statistic equals _____.

A) +3 B) 3.4 C) −3 D) −1.7

85) A recent study of the relationship between social activity and education for a sample of corporate executives showed the following results.

Education College High school Grade school

Above Average 30 20 10

Social Activity Average Below Average 20 10 40 90 50 130

The appropriate test statistic for the analysis is a(n) _______.

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A) z-statistic B) F-statistic C) chi-square statistic D) t-statistic

86) A recent study of the relationship between social activity and education for a sample of corporate executives showed the following results. Use 0.05 as the level of significance.

Education College High school Grade school

Above Average 20 92 16

Social Activity Average 6 118 4

Below Average 6 130 8

What is the value of the chi-square test statistic?

A) 28.222 B) 5.465 C) 26.253 D) 60.174

87) For any chi-square goodness-of-fit test, the number of degrees of freedom is found by _______.

A) n − k − 1 B) n + 1 C) k − 1 D) n + k

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88) Based on the Nielsen ratings, the local CBS affiliate claims its 11 p.m. newscast reaches 41% of the viewing audience in the area. In a survey of 100 viewers, 36% indicated that they watch the late evening news on this local CBS station. What is(are) the critical value(s) if α = 0.01?

A) ±2.576 B) +2.326 C) −2.326 D) +2.576

89) A question has these possible responses: excellent, very good, good, fair, and unsatisfactory. What are the degrees of freedom for a goodness-of-fit test to test the hypothesis that responses are uniformly distributed?

A) 0 B) 4 C) 2 D) 5

90)

Which of the following assumptions is necessary to apply a goodness-of-fit test?

A) The population mean must be known.

B) The population must be normally distributed.

C) The population variance must be known.

D) The data are measured with a nominal or ordinal scale.

91)

What are the degrees of freedom for a contingency table analysis?

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A) Rows − Columns B) (Rows − 1) × (Columns − 1) C) (Rows) × (Columns) D) n − 1

92) It is claimed that in a bushel of peaches, fewer than 10% are defective. A sample of 400 peaches is examined and 50 are found to be defective. If α = 0.025, what will be the decision?

A) Fail to reject the null hypothesis.

B) Reject the nullhypothesis and conclude the defects are not greater than 10%.

C) Reject the nullhypothesis and conclude the defects are greater than 10%.

D) Accept the null hypothesis.

93) If we are testing the difference between two population proportions, it is assumed that the two populations are approximately normal and have equal variances. ⊚ true ⊚ false

94) A personnel manager is concerned about absenteeism. She decides to sample employee records to determine if absenteeism is distributed evenly throughout the six-day workweek. The null hypothesis is: Absenteeism is distributed evenly throughout the week.Use the 0.01 level of significance. The sample results are: Day of the Week Monday Tuesday Wednesday Thursday Friday Saturday

Number of Employees Absent 12 9 11 10 9 9

What is the expected frequency for Wednesday?

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A) 12 B) 11 C) 10 D) 9

95) If 26 out of 50 students sampled live in a college dormitory, what is the estimated proportion of students at the university living in a dormitory?

A) 0.62 B) 0.78 C) 0.52 D) 0.26

96)

The chi-square distribution is _______.

A) negatively skewed B) uniformly distributed C) positively skewed D) normally distributed

97) A distributor of personal computers has five locations in a city. In the year's first quarter, the sales in units were: Location North side Pleasant township Southwick I-90 Venice avenue Total

Observed Sales (units) 70 75 70 50 35 300

For a goodness-of-fit test that sales were the same for all locations, what is the p-value?

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A) 1.0% B) 13.28% C) 0.07% D) 5.0%

98) In chi-square analysis, if there are only two categories, the expected frequency in each category should be at least ten. If not, categories should be combined to increase the expected frequency if logical to do so. ⊚ true ⊚ false

99)

Some important uses of the chi-square distribution include _______.

A) testing for goodness-of-fit B) All of these choices are correct.

C) testing for the association of two categorical variables D) determining whether a variable appears to follow some specified distribution

100) A sample of 100 production workers is obtained. The workers are classified by gender (male, female) and by age (under 20, 20−29, 30−39, and 40 or over).For contingency table analysis, how many degrees of freedom are there?

A) 5 B) 3 C) 0 D) 6

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101) There is not one, but a family of chi-square distributions. There is a chi-square distribution for 1 degree of freedom, another for 2 degrees of freedom, another for 3 degrees of freedom, and so on. ⊚ true ⊚ false

102) Some important uses of the chi-square include testing for the association of two categorical variables. ⊚ true ⊚ false

103) A survey of property owners' opinions about a street-widening project was taken to determine if owners' opinions were related to the distance between their home and the street.The level of significance for this study is 0.05. A randomly selected sample of 100 property owners was contacted and the results are shown next.

Front Footage Under 45 feet 45–120 feet Over 120 feet

For 12 35 3

Opinion Undecided 4 5 2

Against 4 30 5

What is the critical value?

A) 9.488 B) 12.592 C) 15.507 D) 7.779

104) Students were sampled to determine their support for the legalization of gambling in their community. A sample of 150 students were asked whether or not they supported legalization of gambling, and the following results were obtained. Use a 5% level-of-significance.

Do You Support Legal Gambling?

Yes, support

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Number of Students 40 36

No, don't support No opinion

60 50

For a goodness-of-fit test that the category frequencies are the same, what is the p-value?

A) 13.5% B) 0.07% C) 9.21% D) 5.0%

105)

Which of the following statements is correct regarding the goodness-of-fit test?

A) Variables are based on the nominal measurement scale.

B) Population must be normal.

C) All the expected frequencies must be different.

D) All the expected frequencies must be equal.

106) A personnel manager is concerned about absenteeism. She decides to sample employee records to determine if absenteeism is distributed evenly throughout the six-day workweek. The null hypothesis is: Absenteeism is distributed evenly throughout the week. Use the 0.01 level of significance. The sample results are: Day of the Week Monday Tuesday Wednesday Thursday Friday Saturday

Number of Employees Absent 12 9 11 10 9 9

For a goodness-of-fit test that absenteeism is distributed evenly throughout the week, what decision should be made regarding the null hypothesis? Use the 0.01 level of significance.

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A) Reject the null hypothesis. The frequencies are different.

B) Reserve judgment until a larger sample can be taken.

C) Reject the alternate hypothesis. The frequencies are the same.

D) Do not reject the null hypothesis. The frequencies are the same.

107) Recently, students in a marketing research class were interested in the driving behavior of students. Specifically, the marketing students were interested in finding out if exceeding the speed limit was related to gender.The study will use 0.05 as the significance level. They collected the following responses from 100 randomly selected students: Exceeds the Speed Limit

Does Not Exceed the Speed Limit

50 10

15 25

Male Female

What is the value of the test statistic?

A) 5.404 B) 60 C) 95.94 D) 22.161

108) A survey of property owners' opinions about a street-widening project was taken to determine if owners' opinions were related to the distance between their home and the street.The level of significance for this study is 0.05. A randomly selected sample of 100 property owners was contacted and the results are shown next.

Front Footage Under 45 feet 45–120 feet Over 120 feet

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For 12 35 3

Opinion Undecided 4 5 2

Against 4 30 5

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What is the expected frequency for people who are in favor of the project and have less than 45 feet of property foot frontage?

A) 10 B) 50 C) 35 D) 12

109) An electronics retailer believes that, at most, 40% of their cell phone inventory was sold during November. The retailer surveyed 80 dealers and found that 38% of the inventory was sold. Since 38% is less than 40%, is this difference of 2 percentage pointsdue to sampling error or has the level of inventory sold decreased significantly? Test at the 0.05 level of significance.

A) We need to take a larger sample to reach a conclusion.

B) There is not enough information to reach a conclusion.

C) The 2% is a significant difference.

D) We cannot determine if the 2% is a significant difference.

110) A recent study of the relationship between social activity and education for a sample of corporate executives showed the following results. Use 0.05 as the level of significance.

Education College High school Grade school

Above Average 30 20 10

Social Activity Average Below Average 20 10 40 90 50 130

What is the value of the chi-square test statistic?

A) 50.258 B) 9.488 C) 106.919 D) 83.666

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111) Based on the Nielsen ratings, the local CBS affiliate claims its 11 p.m. newscast reaches 41% of the viewing audience in the area. In a survey of 100 viewers, 36% indicated that they watch the late evening news on this local CBS station. What is the alternate hypothesis?

A) H1: µ≠ 0.41 B) H1: π ≠ 0.41 C) H1: π = 0.36 D) H1: π = 0.41

112) Students were sampled to determine their support for the legalization of gambling in their community. A sample of 150 students were asked whether or not they supported legalization of gambling, and the following results were obtained: Do You Support Legal Gambling?

Yes, support No, don't support No opinion

Number of Students 40 60 50

The value of the chi-square test statistic equals _______.

A) 4 B) +3 C) −3 D) −2

113) In the past five years, 45% of the tourists who visited Orlando, Florida, went to see local attractions. The city council recently spent a significant amount of money on advertising and promoting visits to area attractions. They are interested in knowing whether the advertising campaign was effective—whether it increased the proportion of tourists visiting local attractions.

The proper set of hypotheses is _______.

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A) H0:π > 0.45; H1:π ≤ 0.45 B) H0:π < 0.45; H1:π ≥ 0.45 C) H0:π ≤ 0.45; H1:π > 0.45 D) H0:π ≥ 0.45; H1:π < 0.45

114) Recently, students in a marketing research class were interested in the driving behavior of students. Specifically, the marketing students were interested in finding out if exceeding the speed limit was related to gender.The study will use 0.05 as the significance level. They collected the following responses from 100 randomly selected students: Exceeds the Speed Limit

Does Not Exceed the Speed Limit

40 10

25 25

Male Female

What is the value of the test statistic?

A) 83.67 B) 9.890 C) 3.841 D) 50

115) The contingency table for a sample of corporate executives classified by educational level and social activity follows: Education College High school Grade school

Above Average 30 20 10

Social Activity Average Below Average 20 10 40 90 50 130

What does the expected frequency for the "Above Average" social activity and "High school" education equal?

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A) 22.50 B) 28.50 C) 60.00 D) 9.50

116) A distributor of personal computers has five locations in a city. In the year's first quarter, the sales in units were: Location North side Pleasant township Southwick I-90 Venice avenue Total

Observed Sales (units) 70 75 70 50 35 300

For a goodness-of-fit test that sales were the same for all locations, what is the critical value at the 0.01 level of significance?

A) 7.779 B) 15.033 C) 13.277 D) 5.412

117) The claim that "40% of those persons who retired from an industrial job before the age of 60 would return to work if a suitable job was available" is to be investigated at the 0.02 significance level. If 74 out of the 200 workers sampled said they would return to work, what is our decision?

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A) Do not reject the null hypothesis because −0.866 lies in the region between +2.576 and −2.576.

B) Do not reject the null hypothesis because 37% lies in the area between 0% and 40%.

C) Do not reject the null hypothesis because −0.866 lies in the region between +2.326 and −2.326.

D) Reject the null hypothesis because 37% is less than 40%.

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Answer Key Test name: Chap 15_10e_Lind 1) A 2) A 3) D 4) C 5) B 6) A 7) C 8) A 9) A 10) A 11) D 12) B 13) D 14) A 15) TRUE 16) TRUE 17) A 18) A 19) A 20) D 21) C 22) A 23) A 24) D 25) B 26) D Version 1

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27) A 28) B 29) C 30) B 31) FALSE 32) B 33) C 34) B 35) D 36) TRUE 37) FALSE 38) D 39) C 40) TRUE 41) B 42) C 43) TRUE 44) A 45) TRUE 46) B 47) D 48) C 49) C 50) D 51) A 52) C 53) C 54) B 55) B 56) B Version 1

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57) D 58) B 59) B 60) C 61) FALSE 62) A 63) A 64) B 65) D 66) D 67) C 68) C 69) A 70) FALSE 71) C 72) A 73) TRUE 74) B 75) D 76) FALSE 77) A 78) B 79) B 80) A 81) B 82) A 83) D 84) B 85) C 86) C Version 1

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87) C 88) A 89) B 90) D 91) B 92) A 93) FALSE 94) C 95) C 96) C 97) C 98) FALSE 99) B 100) B 101) TRUE 102) TRUE 103) A 104) A 105) A 106) D 107) D 108) A 109) D 110) D 111) B 112) A 113) C 114) B 115) A 116) C Version 1

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117) C

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