Analyzing Data and Making Decisions Statistics for Business Microsoft Excel 2010 Updated 2e Judith Skuce (Test Bank All Chapters, 100% Original Verified, A+ Grade) Answers At The End Of Each Chapter Chapter 1 MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) In a city of 50,000 households, 200 were randomly sampled and the heating bill for January was recorded. The standard deviation of these 100 values was then computed. The standard deviation is a: A) parameter B) interquartile range C) range D) statistic
1)
2) A scientist is testing the hardness of a new type of ceramic and controls the contents of the mixture as well as the oven temperature. This is an example of: A) a longitudinal study B) an experimental study C) an observational study D) a cross-sectional study
2)
3) A scientific team collects water samples from a fresh-water lake to measure levels of a certain pollutant. For the team, this constitutes: A) tertiary data B) primary data C) population data D) secondary data
3)
4) You have a population of 500 numbers from which you wish to randomly sample 50 of them. The best approach is: A) sort the data from lowest to highest and pick the first 50 B) add the digits in each number, sort by the sum and pick the first 50 C) put the data in a spreadsheet column, generate random numbers in the next column, sort by the random numbers and pick the first 50 D) sort by the number of threes in each number and pick the first 50
4)
5) A polling firm conducts a survey for a political party to determine the level of support for the party's policies. If a third party then observes the poll results, for this third party this constitutes: A) population data B) tertiary data C) secondary data D) primary data
5)
6) A survey has a convoluted question in which the respondent might answer incorrectly in spite of not clearly understanding the question. This is an example of: A) coverage error B) sampling error C) processing error D) response error
6)
7) A secretary does data entry for a survey conducted by paper. If a value is entered incorrectly, this is an example of: A) sampling error B) nonresponse error C) coverage error D) processing error
7)
8) You interview people coming out of a store to see how much they spent. The data type is: A) secondary B) six-sigma C) primary D) tertiary
8)
1
9) Restaurants have survey cards that people can fill out. The people who fill out the cards are an example of: A) self-selected sample B) stratified sample C) convenience sample D) simple random sample
9)
10) You ask all the residents of an apartment building how many times a month they eat out and then compute the average for all the residents. This average is a: A) median B) parameter C) statistic D) mode
10)
11) You have a list of people to call for a survey. However, the list is 5 years old. This is an example of: A) coverage error B) processing error C) nonresponse error D) sampling error
11)
12) A class of 60 students writes a test out of which you randomly sample 10. The difference between the average of this sample and that of the entire class is an example of: A) sampling error B) processing error C) nonresponse error D) coverage error
12)
13) In a city of 100,000 people, you survey 100 of them to ask how much they spend per month on gasoline. You then compute the average for this sample of 100 people This average is a: A) statistic B) mode C) parameter D) median
13)
14) A computer was used to calculate certain statistics from data. However, one of the formulas was set up incorrectly. This is an example of: A) sampling error B) processing error C) estimation error D) response error
14)
15) You mail a survey to 500 people, but receive back only 67. This is an example of: A) processing error B) nonresponse error C) coverage error D) sampling error
15)
16) You consult a Stats Canada publication to find out the populations of a number of cities. The data type is: A) tertiary B) six-sigma C) primary D) secondary
16)
17) While standing outside a store, you record the gender of a person coming out of the store. This is an example of: A) a longitudinal study B) an observational study C) a cross-sectional study D) an experimental study
17)
18) A poll was conducted of executives in a certain industry. However, not all of them could be contacted in the time frame of the survey. This is an example of: A) nonresponse error B) estimation error C) processing error D) sampling error
18)
19) Polling firms can sample telephone numbers for any city in Canada from a CD. If a polling firm samples 1,000 numbers for a city of 500,000 from a CD with no regard for what part of the city the number is from, this is an example of: A) stratified sample B) convenience sample C) self-selected sample D) simple random sample
19)
2
20) A store, upon opening, handed out a survey to the first 10 customers that came in. This is an example of: A) convenience sample B) self-selected sample C) cluster sample D) simple random sample
20)
21) In a survey of 1,000 Canadian households, a polling firm asked the respondents how much they spend per month on entertainment. The firm then calculated the standard deviation of the 1,000 values. The difference between the standard deviation of this sample and that of the entire population is an example of: A) coverage error B) sampling error C) processing error D) nonresponse error
21)
22) You post a poll on a website in which a maximum of 100 respondents is allowed. This is an example of: A) cluster sample B) self-selected sample C) simple random sample D) stratified sample
22)
23) A researcher in a grocery store takes note of whether a customer goes to a regular checkout or the express checkout. This is an example of: A) an experimental study B) a longitudinal study C) an observational study D) a cross-sectional study
23)
24) In a factory with 100 workers, management computed the total number of sick days in the previous year for each worker. They then computed the standard deviation of the number of sick days for all the workers. The standard deviation is a: A) range B) interquartile range C) parameter D) statistic
24)
25) A researcher is comparing twins on the length of time to complete a test. The researcher designed the test and uses an accurate watch to time the results. This is an example of: A) an observational study B) a cross-sectional study C) an experimental study D) a longitudinal study
25)
SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. 26) A person is doing data entry from a paper survey. If the person makes a mistake entering a value, in a word, what type of error is this?
26)
27) You are sitting outside a store, counting how many people per hour enter it. In a word, what type of study is this?
27)
28) You conduct a one-question survey with the first 5 students entering a classroom. In a word, what type of sample is this?
28)
29) You are trying to phone IT executives to conduct a survey. However, most of them have voice mail set up to capture incoming calls; consequently you never reach them. In a word, what type of error is this?
29)
3
30) A scientist designs a study to measure the amount of impurities removed from oil samples, carefully controlling the factors which may impact the results. In a word, what type of study is this?
30)
31) You conduct a door-to-door survey to see if the residents own or rent. In a word, what type of data is this?
31)
32) An interviewer inflects his/her voice in such a way that it may influence the answer given by the respondent. In a word, what type of error is this?
32)
33) In a company with 12 employees, you ask all 12 of them how many hours a week they work. If you compute the average of all 12 data points, in a word, what is this an example of?
33)
34) In a city of 500,000 people, 500 were surveyed to determine how many times per month they take public transit. If the mean of this sample is computed, in a word, what type of error is the difference between this mean and the population mean?
34)
35) In a company with 500 employees, you sample 50 and examine how many sick days they took last year. If you compute the standard deviation of these 50 data points, in a word, what is this an example of?
35)
36) You read the results of a research study in a journal. The data is listed in an appendix. If you use this data, what type of data is it, in a word?
36)
37) You have a list of people to call for a survey but you are not sure how old the list is. If you call a number of this list and find it is out of service, in a word, what type of error is this?
37)
38) This Section Intentionally Left Blank
38)
39) You examine the results of a survey conducted in 1999 asking companies which of them were Y2K ready. In a word, what type of data is this?
39)
40) You conduct an experiment in which you measure the amount of methane produced by a certain chemical reaction. In a word, what type of data is this?
40)
41) In a survey, people are willing to answer the main questions, but reluctant to answer demographic questions such as income. If a person does not answer the income question, in a word, what type of error is this?
41)
TRUE/FALSE. Write 'T' if the statement is true and 'F' if the statement is false. 42) A question in a survey is phrased in such a way so as to elicit a certain response. This is an example of response error.
42)
43) A frame is essentially a database of a population.
43)
44) In 1995, a group of researchers interviewed people to find out which of them used email. If you look up the results of this research, this would be an example of secondary data.
44)
4
45) In a simple random sample of students at a university, some students are more likely to be chosen than others because some faculties are larger than others.
45)
46) A spreadsheet is used to calculate a certain formula. If the formula is incorrect, this is an example of a processing error.
46)
47) A class of 50 students wrote a test. Afterward, the teacher computed the standard deviation for all 50 students. This standard deviation is a parameter.
47)
48) A newspaper put a poll on its website and then published the results. The people who did the poll is an example of a self-selected sample.
48)
49) A mall conducted a survey with the first 10 people who walked through the door. Since we don't know who would come through the door, this is an example of a simple random sample.
49)
50) If you conduct a survey to determine the average amount per month that companies spend on office supplies, the difference between the mean calculated from the survey and the population mean is known as sampling error.
50)
51) A city examined each household in the city to determine the average number of people per household. This average is a statistic.
51)
52) Descriptive statistics are used to summarize raw data.
52)
53) A market research firm will call potential respondents up to 6 times in an attempt to reach them before giving up. If these respondents are not reached, this is an example of response error.
53)
54) A scientist sets up an experiment to measure the boiling point of a certain liquid under various barometric pressures. This is an example of an observational study.
54)
55) A company sets up 2 displays in a store of the same product to see if women are more likely to stop at one display than the other. This is an example of an experimental study.
55)
56) This is an appropriate statement to put in a report aimed at a non-technical audience: We reject the null hypothesis if the test statistic is greater than 1.645.
56)
57) A survey of 1,000 people in a province was conducted to see which of them would vote for a certain party in the next election. The percentage of these people who would do so is a statistic.
57)
58) You are calling people for a survey using a frame purchased from a sampling firm. However, some listings occur more than once in the frame. This would be an example of coverage error.
58)
59) You survey a group of people to find out how far they drive to work. This is an example of primary data.
59)
60) A researcher mailed out a consumer survey, but not everyone replied. This is an example of sampling error.
60)
5
61) You survey a group of people to find out whether or not they recycle at least once a month. This is an example of secondary data.
6
61)
Answer Key Testname: CHAPTER 1 1) D 2) B 3) B 4) C 5) C 6) D 7) D 8) C 9) A 10) B 11) A 12) A 13) A 14) C 15) B 16) D 17) B 18) A 19) D 20) A 21) B 22) B 23) C 24) C 25) C 26) processing 27) observational 28) convenience 29) nonresponse 30) experimental 31) primary 32) response 33) parameter 34) sampling 35) statistic 36) secondary 37) coverage 38) 39) secondary 40) primary 41) response 42) TRUE 43) TRUE 44) TRUE 45) FALSE 46) FALSE 47) TRUE 48) TRUE 49) FALSE 50) TRUE 7
Answer Key Testname: CHAPTER 1 51) FALSE 52) TRUE 53) FALSE 54) FALSE 55) FALSE 56) FALSE 57) TRUE 58) TRUE 59) TRUE 60) FALSE 61) FALSE
8
Chapter 2 Exam Name___________________________________
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) A frequency table has the following classes: 24 to under 36, 36 to under 48, 48 to under 60, etc. The class width is: A) 12 B) 11.99 C) 12.01 D) 24
1)
2) The following table summarizes respondents' agreement with a certain statement: Strongly disagree Somewhat disagree Somewhat agree Strongly agree 132 264 302 169 In creating a bar chart, the appropriate starting point for the y-axis is: A) 130 B) 100 C) 0 D) 50
2)
3) The number of times per week a person eats out can be categorized as: A) nominal data B) discrete data C) continuous data D) ordinal data
3)
4) The following frequency table is provided to explain the number of home sales in the West Side of Vancouver by price category:, and the number of unit sold: Class { price range] Frequency [# of homes sold] 250-279.9 162 280-309.9 128 310-349.9 96 350-389.9 66 390-469.9 43 470-549.9 11
4)
Compute the relative frequency of [470-549.9] class A) 162/506 B) 11/506
C) 43/506
5) You are given the following frequency table: Class Frequency 0 to under 5 2 5 to under 10 8 10 to under 15 6 15 to under 20 9 The percentage of values that are less than 10 is: A) 40% B) 32%
D) 66/506 5)
C) 25%
D) 44%
6) A university professors lists a number of high income earning companies on the NASDAQ Stock Exchange, by the name of the company. This is an example of: A) ordinal scale B) nominal scale C) interval scale D) quantitative variable
1
6)
7) The following table summarizes annual charitable contributions: 0 to under $20 5% $20 to under $40 16% $40 to under $60 79% The data may be characterized as: A) continuous data B) ordinal data C) discrete data D) nominal data
7)
8) A scatterplot's origin is at (100,50). An appropriate lowest value for the x-axis is: A) 324 B) 205 C) 105 D) 184
8)
9) A pie chart has the following labels: Poor 12%, Average 54%, Good 25%, Excellent 9%. If the pie chart is based on a survey of 800 people, how many chose good or excellent? A) 280 B) 264 C) 256 D) 272
9)
10) The following frequency table is provided to explain the number of home sales in the West Side of Vancouver by price category:, and the number of unit sold: Class { price range] Frequency [# of homes sold] 250-279.9 162 280-309.9 128 310-349.9 96 350-389.9 66 390-469.9 43 470-549.9 11
10)
What is the cumulative frequency of [390-469.9] class: A) 506 B) 495 C) 452
11) The data from a sample is provided: Class Frequency 10-24 10 25-49 30 50-74 50 75-99 40 100-114 20 115-124 10 What is the lower limit of the third class? A) 100 B) 50
D) 162 11)
C) 10
D) 25
12) You are creating a frequency table in which the smallest data value is $2.36 and the largest is $114.62. If you are using a class width of $25, the number of classes in the table is: A) 4 B) 7 C) 6 D) 5
12)
13) A company had a table of its gross annual income (thousands) by year: Year 2000 2001 2002 2003 2004 Income 13.2 25.4 20.6 29.6 34.7 If you wished to examine a linear trend from year to year, the appropriate graph is: A) scatter diagram B) bar chart C) histogram D) pie chart
13)
2
14) You are given the following table of how people voted in the last election: Party A 24% Party B 38% Party C 32% Party D 6% The appropriate graph is: A) time series graph B) histogram C) bar chart D) scatter diagram
14)
15) A certain stem and leaf plot has the stem unit = 10 and the leaf unit = 1. The stem value of 154.3 would be: A) 3 B) 1 C) 15 D) 4
15)
16) A researcher had the following table summarizing the number of employees at a company and gross annual revenues (millions): Employees 62 89 162 208 312 Revenue 1.3 2.8 5.6 7.9 10.4 When creating a scatterplot of this data, an appropriate origin would be: A) (25,0) B) (60,1) C) (70,2) D) (0,0)
16)
17) One thousand consumers rank a financial product in a bank, with the following scale. poor fair good very good excellent What will be the difficulty of using such a ranking to find the median response? A) nonnumeric data is difficult to tabulate B) it is difficult to rank data in an increasing order C) large data sets make it difficult to set up frequency tables D) data needs to be converted to a numeric (quantitative) scale
17)
18) Consider the following table of how people rate the service at a store on a scale from 1 to 5, 1 = poor, 5 = excellent: Rating 1 2 3 4 5 Frequency 24 68 132 267 192 In creating a pie chart, what percentage of the pie would the combined ratings of 1 and 2 occupy? A) 13.47% B) 13.58% C) 13.4% D) 13.52%
18)
19) According to Globe and Mail newspaper, the following Canadian companies fewer than five thousand employees , had the following average sales per each employee Size of Average sales company per employee [number of [Thousands of employees] Dollars] 1-4 112 5-19 128 20-99 127 100-499 118 500-4999 120 Estimate the average sales per employee for all the firms having fewer then five thousand employees A) $120,000 B) $125,000 C) $112,000 D) $121,000
19)
3
20) You are given the following contingency table of income by gender: Under $25K $25K to under $50K $50K to under $75K Male 62 78 92 Female 56 84 98 The appropriate graph in which gender runs along the x-axis is: A) histogram B) scatter diagram C) pie chart
20) $75K or over 24 18
D) bar chart
21) A trucking company had a table of travel distances (im) and the average number of hours estimated to travel that distance: Distance 100 250 400 500 800 Time 1.2 3.1 4.8 6.25 10.2 The appropriate graph is: A) scatter diagram B) pie chart C) histogram D) bar chart
21)
22) Statistics Canada recently collected average gas prices posted at the gas stations in Vancouver over the last five years. This type of data can be considered as: A) nominal scale data B) cross-sectional data C) ratio scale data D) time series data
22)
23) In a survey, people were asked to name their favourite pet. The spreadsheet labelled dog = 1, cat = 2, budgie = 3, etc. This data can be categorized as: A) nominal data B) continuous data C) ordinal data D) discrete data
23)
24) A frequency table has the following rows: 0 to under 10 8 10 to under 20 16 etc. The appropriate graph is: A) histogram B) pie chart
24)
C) scatter diagram
D) bar chart
25) A bar chart of people's agreement with a statement had the following heights for their respective categories: Strongly disagree Somewhat disagree Somewhat agree Strongly agree 12 74 198 62 If this were remade into a pie chart, what percentage of the pie would be occupied by those who disagree with the statement, either strongly or somewhat? A) 21.39% B) 24% C) 25% D) 24.86%
25)
26) You want to create a frequency table on Excel using the class 0 to under $50, $50 to under $100, $100 to under $150, etc. The bin value for the second class is: A) 100 B) 99.99 C) 100.01 D) 149.99
26)
27) You are given the following partial frequency table: 0 to under 2.5 17 2.5 to under 5.0 26 5 to under 7.5 42 What is the upper class limit of the fifth class? A) 10.0 B) 15.0
27)
C) 17.5
4
D) 12.5
28) A certain stem and leaf plot has the stem unit = 1 and the leaf unit = 0.1. The leaf value of 1.243 would be: A) 243 B) 1 C) 2 D) 0.2
28)
29) In a survey, people were asked to rate their agreement with a statement on a scale from 1 to 5, 1 = strongly disagree, 5 = strongly agree. This data can be categorized as: A) discrete data B) continuous data C) ordinal data D) nominal data
29)
30) You are given the following frequency table of daily sales at a store for the month of March: Class Frequency 0 to under $2000 6 $2000 to under $4000 11 $4000 to under $6000 8 $6000 to under $8000 6 The percentage of days in which the store had at least $4000 in sales is: A) 74.19% B) 45.16% C) 54.84% D) 25.81%
30)
31) The price of a car can be categorized as: A) nominal data C) continuous data
31)
B) discrete data D) ordinal data
32) You are creating a frequency table on Excel showing the distribution of how many times a year people recycle. The classes are 0 to 1, 2 to 3, 4 to 5, etc. The bin value for the first class is: A) 3 B) 2 C) 0 D) 1 SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. 33) You are using a 7-point scale to rate people's satisfaction with a service where 1 = extremely dissatisfied and 7 = extremely satisfied. What would be the numeric value of neither satisfied nor dissatisfied?
33)
34) Transport Canada [TC] is concerned about the rising jet fuel costs and its negative impact on the Canadian airlines. TC recently conducted a survey of the number passengers flown into Vancouver with particular airline to assess if the passenger load capacity is declining over time. Data is provided: Passengers in Airline (thousands) Air Canada 277 West Jet 350 Continental 200 Alaska 150 What would be the best non-tabular form of analyzing this data set ?
34)
35) You have a frequency table with the following classes: $70 to under $105, $105 to under $140, $140 to under $175, etc. What is the class width?
35)
36) You are creating a frequency table using Excel. The first 2 classes are 0 to under $30 and $30 to under $60. What is the bin value of the second class?
36)
5
32)
37) A statistics professor decides to create a data set of student achievement in his class. He creates the following frequency table Degree of Relative achievement Frequency frequency (%) High achiever 55 26.6 Medium achiever 67 32.4 Low achiever 77 37.2 Poor performer 8 3.9 Total 207 100 The professor is is does not find this table to useful for distribution of student performance. He would rather see the results in a non-tabular form. What type of graph would be the best way of presenting this data?
37)
38) You have a scatter plot in which two of the points are (2,3) and (3,7). If you draw a straight line through these points, for an x value of 4, what is the y value of the point that lies on this line?
38)
39) You are creating a stem and leaf plot with the stem unit = 10 and leaf unit = 1. What is the stem value of 262.9?
39)
40) You are computing a class width by hand. The smallest value is 2.5, the largest is 60.2 and there are 25 data points. What is the class width, round to the nearest whole number?
40)
41) You have a time series graph of a company's gross annual sales in thousands of dollars. Two of the points are (1910,4.1) and (1911,3.6). If you draw a straight line through these 2 points, what would be the gross sales value on the line for the year 1913?
41)
42) A contingency table was created from a survey in which upper management, middle management and non-management staff were asked to rate a courier on a scale from 1 to 10. Suppose the ratings are grouped 1-3, 4-6, 7-9, and 10 in the contingency table. If a bar chart is created from the table and the staff positions occupy the x-axis, how many categories are in the legend?
42)
43) A frequency table has the following classes: 0 to under $9, $9 to under $18, $18 to under $27, etc. What is the lower class limit of the sixth class?
43)
44) The following table is from a survey in which people were asked how many times per week they eat out: Class Frequency 0 68 1 192 2 98 3 42 What percentage of the respondents eat out no more than once a week. Express your answer as a decimal number.
44)
45) You have a scatter plot in which the smallest data point is (1432.7, 680.6). If the origin should be a multiple of 30, what should be the y value of the origin?
45)
6
46) A firm's annual sales, in thousands of dollars, for the past 10 years are as follows: 105,210,322,330,362,368,420,425,435,440 The analyst wishes to represent this data in a graphical form. What would the type of graph that is best suited for such a data set ?
46)
47) You have the following stem and leaf plot in which the stem unit = 1 and leaf unit = 0.1: 0 12334 1 0112556 2 003446889 3 1455568 If you create a frequency table with the first class being 0 to under 2, what is the frequency of that class?
47)
48) A survey asked people how interested they would be in a new type of cell phone: Not at all Not very Somewhat Very 142 57 24 13 What percentage of the respondents are at least somewhat interested? Express your answer as a decimal number accurate to 4 decimals.
48)
49) You are using the following table to create a pie chart: Poor Fair Good Excellent 25 89 163 272 In the pie chart, what percentage of the pie is occupied by those giving either a good or excellent rating? Express your answer as a decimal number accurate to 4 decimals.
49)
50) You are creating a histogram from a frequency table in which the first class is 0 to under 25 and the last class is 175 to under 200. If each class has the same width, how many bars will the histogram have?
50)
TRUE/FALSE. Write 'T' if the statement is true and 'F' if the statement is false. 51) In a survey, people were asked which party they would likely vote for in the next election. A number representing a party was entered into a spreadsheet. This data would be considered nominal.
51)
52) A scatter diagram plots number of monthly sales along the x-axis and gross income along the y-axis. The fewest number of sales is 1 while the highest is 10. The lowest gross income is $8.50 while the highest is $64.50. An appropriate origin for this graph would be (0,0).
52)
53) A frequency table summarized annual gross sales for a set of 100 companies. This data would be classified as continuous.
53)
54) A certain stem and leaf plot has a stem unit of 1 and leaf unit of 0.1. The leaf value of 2.03 would be 3.
54)
55) You are creating a frequency table in which the first 2 classes are 0 to under $4.50 and $4.50 to under $9.00. The upper class limit of the fifth class would be $22.50.
55)
7
56) Consider the following table: Office Workers Doctors Income < $100K 1800 20 Income at least $100K 200 180 Total 2000 200 In creating a bar graph from this data, the scale along the y-axis should be a frequency scale to get a sense of the number of people in each occupation group earning at least $100,000 per year.
56)
57) In creating a scatter diagram, another name for the response variable is the dependent variable and is plotted along the y-axis.
57)
58) The following data is based on a recent daily product sales in a grocery store Number of Price $ sales $18-20.99 2 21-23.99 7 24-26.99 7 27-29.99 5 30-32.99 4 Total 25 The store manager wishes to expand this data set into a full frequency table. The next two columns in this table will be "relative frequency" and "probability of cumulative frequency."
58)
59) In creating a scatter diagram, the data for the y-axis does not necessarily have to be quantitative.
59)
60) You have a table with sales dates and the number of units sold on those dates. If you wish to track a linear trend from one date to the next, the appropriate graph is a histogram.
60)
61) If you were creating a frequency table using Excel and the first class was 0 to under $25, the bin value for this class would be $24.99.
61)
62) The title of a chart is not important, so long as the actual chart coveys the necessary information.
62)
63) If people rate an ad on a scale from 1 to 5, 1 = poor and 5 = excellent, the data is classified as ordinal.
63)
64) In plotting simultaneous histograms to compare data from different sources, it is not important to use the same x-axis for the histograms.
64)
65) We may depict the information contained in frequency distributions as bar graphs known as frequency tables.
65)
66) The primary difference in the x-axis between a histogram and a bar chart is that, for a histogram, the data is qualitative while that of a bar chart is quantitative.
66)
67) The cumulative frequency of a class is the sum of the frequency of the class and all preceding classes.
67)
8
68) You have a contingency table consisting of 4 income categories and 3 job descriptions. If the job descriptions are used as the x-axis of a bar graph, the legend would have 3 categories.
68)
69) A store conducted a survey and grouped people by their overall satisfaction with the service: Neither Very Somewhat satisfied nor Somewhat Very dissatisfied dissatisfied dissatisfied satisfied satisfied 2 12 98 164 132 If this data were plotted in a bar chart, it would appear to be skewed left.
69)
70) In a survey, people were asked how many times a month they order out for pizza. This data would be classified as discrete.
70)
71) When creating a bar graph or histogram, the appropriate starting point for the y-axis is zero.
71)
72) The annual household incomes of people in a city were summarized as follows: Class Frequency Under $25K 1624 $25K to under $50K 5609 $50K to under $75K 8284 $75K to under $100K 2098 The appropriate graph for this data is a bar chart.
72)
73) A 3-D pie chart is more informative than a 2-D pie chart.
73)
9
Answer Key Testname: CHAPTER 2 1) A 2) C 3) B 4) B 5) A 6) B 7) A 8) C 9) D 10) B 11) B 12) D 13) A 14) C 15) C 16) B 17) B 18) A 19) D 20) D 21) A 22) D 23) A 24) A 25) D 26) B 27) D 28) C 29) C 30) B 31) C 32) D 33) 4
10
Answer Key Testname: CHAPTER 2 34) Pie chart would be the best option with the data labels. A historical data base may also be required to see if there is indeed a decline with the passenger loads over time.
35) 35 36) 59.99
11
Answer Key Testname: CHAPTER 2 37) A pie chart, as displayed below
38) 11 39) 26 40) 12 41) 2.6 42) 4 43) 45 44) 0.65 45) 660
12
Answer Key Testname: CHAPTER 2 46) A time series line will be the best graphical representation, as sales trend can best be depicted over time. The linearity of the line can be further tested
47) 12 48) 0.1568 49) 0.7923 50) 8 51) TRUE 52) TRUE 53) TRUE 54) FALSE 55) TRUE 56) FALSE 57) TRUE 58) FALSE 59) FALSE 60) FALSE 61) TRUE 62) FALSE 63) TRUE 64) FALSE 65) FALSE 66) FALSE 67) TRUE 68) FALSE 69) TRUE 70) TRUE 71) TRUE 72) FALSE 73) FALSE
13
Chapter 3 Exam Name___________________________________
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) For a set of data of x and y, you are told that r = -0.002. If you plot the data, what would you expect? A) The data appears somewhat linear, sloping upward to the left B) The data appears slightly linear, sloping upward to the left C) The data will have no discernable pattern D) The data appears somewhat linear, sloping upward to the right
1)
2) A researcher sampled 6 households to determine the correlation of annual household income (thousands of dollars) to the amount spent monthly on entertainment: Income 25.2 30.6 42.7 49.8 57.8 62.9 Entertainment 100 135 162 198 207 508 It is determined that the last data point has an adverse impact on the linear relationship of the two variables. If it is removed, what is the ratio of the new correlation coefficient to the original one? A) 0.75 B) 0.8 C) 1.25 D) 1.33
2)
3) The Construction Association of BC reports the following data on the average construction completion time, in months: Average Construction Year time [months] 1980 46 1981 50 1982 55 1983 50 1984 40 1985 76 1986 82 1987 89 1988 90 Find the Pearson correlation coefficient for construction completion time as a function of time. A) 0.86 B) 0.75 C) 0.80 D) 0.90
3)
4) Given this set {2, 8, 15, 20, 350}, it would appear that 350 is an extreme value. If it is removed, how much does the mean reduce by? A) 70 B) 67.75 C) 72 D) 62.25
4)
5) You have a sample of 5 numbers representing the number of times per week that people eat out. The mean of this sample is 2.4. You interview a sixth person and find this person eats out twice a week. What is the mean now? A) 2.33 B) 2.4 C) 2.5 D) 2.0
5)
6) Find the covariance coefficient for the given data set 20, 36, 29, 42, 37, 48 21, 22, 29, 35, 39, 42 A) 59 B) 54
6)
1
C) 57
D) 58
7) A researcher asked 50 people how many times a week they watch TV; the average was 6.2. However, the next 2 people told the researchers they do not watch TV at all. What is the average now, accurate to 2 decimals? A) 5.96 B) 5.87 C) 5.98 D) 6.2
7)
8) Given x = {1, 7, 9, 16}, what is x2 ? A) 804 B) 625
8)
C) 1,089
D) 387
9) A researcher asked a sample of 9 people how much per week they spend on groceries. The values are $100, $120, $90, $135, $250, $75, $160, $180 and $120. If we remove the largest value, how much does the IQR change by if the needed percentiles are computed by hand? A) 12.5 B) 15 C) 13.75 D) 0.5
9)
10) Find the range of the following data 18,6,14,27,12,44,38,33 A) 38 B) 38.5
10) C) 39
D) 37
11) For a set of 12 numbers, the seventy-fifth percentile is 111.75. If the ninth value in the data set is 108, what is the tenth value? A) 110.5 B) 113 C) 109.25 D) 114.75
11)
12) Given this data set {12, 62, 135, 457, 609, 834, 937, 1,024, 1,368, 1,567}, what is the numerical difference between the median and the twenty-fifth percentile if they are computed by hand? A) 615.25 B) 575.25 C) 604.75 D) 510.5
12)
13) Compute the first quartile (QR 1) of the following data set 5, 5,10,12, 14, 15, 17, 17, 18, 19, 19 , 20 A) 12 B) 19 C) 5
13) D) 11
14) A clothing store had 9 sales on a certain day in which the average sale was $150. Before the store closed, it had a customer who spent $875. How much did the average increase by? A) 77.50 B) 67.50 C) 72.50 D) 82.50
14)
15) For this set of numbers {12, 17, 21, 29, 33, 37, 46, 55, 64, 78}, what is the sixty-second percentile if it is computed by hand? A) 44.38 B) 38.8 C) 40.52 D) 39.78
15)
16) You have a set of 8 numbers, of which 5 are 1, 5, 9, 16 and 18. The remaining 3 numbers are the mode. If the mean of these 8 numbers is 7.25, what is the mode? A) 9 B) 2 C) 3 D) 5
16)
17) A researcher investigated the relation between annual gross revenues (in thousands of dollars) and annual technology expenditures in (thousands of dollars): Revenue 56 62 78 98 105 150 Technology 0.62 1.3 1.67 2.98 4.06 5.78 When a seventh company was surveyed, its annual gross revenues were $75,000 but its technology expenditures were $9,230. If this data point is included, what is the ratio of the original correlation coefficient to the new one? A) 2.06 B) 0.67 C) 0.41 D) 2.42
17)
2
18) Suppose the amount that people spend per week on groceries follows a bell curve with an average of $150 and standard deviation of $42. What is the most that people spend on groceries 95% of the time? A) $276 B) $22 C) $228 D) $234
18)
19) The hours wages of employees at Extra Company were recorded as follows Hourly Wages Number of [$] Employees $5-5.99 20 $6-6.99 35 $7-7.99 48 $8-8.99 167 $9-9.99 55 $10-10.99 25 Estimate the mean, variance and standard deviation of hourly wages A) $1.205, $1.455 and $1.287 B) $8.332, $1.552 and$1.201 C) $8.286, $1.211 and $1.541 D) $8.286, $1.451 and $1.205
19)
20) For a set of 8 numbers, the mean is 58.625. The sum of the 7 lowest numbers is 377. The lowest value is 11. What is the range? A) 81 B) 85 C) 83 D) 75
20)
21) Given this sample of numbers {6, 12, 21, 29, 31, 39, 42}, what is the interquartile range if the values are computed by hand? A) 19 B) 17 C) 27 D) 4
21)
22) For the past six years, Esta Company's annual sales, in millions of dollars, have been: 46.2,48.8,55.7,59.3,62.4,66.0 Find Esta's mean and median annual sales. A) $56.4, $54.5 B) $55.3, $54.5 C) $57.5, $56.0 D) $56.4, $57.5
22)
23) Given this data set {15, 18, 23, 28, 32, 39, 41, 48, 55, 162}, it is assumed that 162 is an extreme value. If it removed, how much does the IQR change if the appropriate percentiles are computed by hand? A) 6 B) 2 C) 4 D) 0
23)
24) The average sale at a discount store is $47.75 with a standard deviation of $7.45. Find the smallest interval such that 90% of the store's sales are within the interval. A) [$25.15, $77.43] B) [$24.00, $70.00] C) [$24.19 , $71.31] D) [$24.19, $72.45]
24)
25) Given {5, 15, 20, 30}, what is (x-18)2 ? A) 4 B) 326
25)
C) 1,550
3
D) 180
26) A store takes a sample of one hundred customers' charge accounts and finds the following: Balance Outstanding Number of ($) accounts 10,000 10 15,555 12 17,000 18 19,999 21 25,999 37 Compute the standard deviation of the balance outstanding variable. A) $5,885 B) $6,500 C) $2,631
26)
D) $6,100
27) For a sample of 9 numbers, you are told the standard deviation is 6.4 and that x2 = 580.49. What is the mean? A) 5.30 B) 5.02 C) 5.34 D) 4.85
27)
28) A sample of 5 number is taken. The mean of this sample is 25. Four of the numbers are 17, 19, 30 and 35. What is the fifth number? A) -1 B) 24 C) 25 D) 18
28)
29) Given this sample data set {9.2, 6.8, 10.6, 13.2, 13, 14.3, 4.5, 9.4, 12.7, 7.3, 8.7}, if it can be assumed the data is symmetric, what percentage lies within 1 standard deviation of the mean? A) 81.82% B) 72.73% C) 54.55% D) 63.64%
29)
4
30) A store takes a sample of one hundred customers' charge accounts and finds the following: Balance Outstanding Number of ($) accounts 10,000 10 15,555 12 17,000 18 19,999 21 25,999 37 Determine if there is a significant degree of association between the balance outstanding on the charge accounts and the number of accounts. Estimate the Pearson Correlation Coefficient and comment on your findings A) Correlation Coefficient ($) No of Accounts ($) Balance 1 Number of accts 0.877777 1 There is a positive correlationary relationship between the two variables B) Correlation Coefficient ($) No of Accounts ($) Balance 1 Number of 0.94949236 1 accounts There is very strong positive correlationary relationship between the account balances and the number of accounts. Coefficient value = 94.9% C) There is no visible relationship between these variables thus no need to run the correlation application D) Account balances and the number of accounts can not be related as the level of account balances is a function of sales and not the number of accounts, thus no need to run the correlation application
30)
31) Given this sample of numbers {5, 12, 18, 36, 269}, it would appear that 269 is an extreme value. If it is removed, what is the ratio of the larger standard deviation to the smaller one? A) 8.51 B) 8.65 C) 8.79 D) 8.62
31)
32) A data set is skewed right if the mean is greater than the median. For a set of 6 numbers, the first 5 are 3, 14, 24, 36 and 63. The sum of the 6 numbers is 240. What is the difference between the mean and the median? A) 16 B) 10 C) 4 D) 12
32)
33) The percentage of gross income that people give to charity follows a bell curve with an average of 2.3% and standard deviation of 0.72%. What is the largest percentage of gross income that people would be expected to give based on this distribution? A) 4.52% B) 3.74% C) 3.02% D) 4.46%
33)
34) You have a set of 5 numbers and find the mean to be 9.4. Four of the numbers are 3, 7, 13 and 15. What is the median of this data set? A) 8.7 B) 12.3 C) 9 D) 10.2
34)
5
35) A store takes a sample of one hundred customers' charge accounts and finds the following: Balance Outstanding Number of ($) accounts 10,000 10 15,555 12 17,000 18 19,999 21 25,999 37 Compute the variance of the balance outstanding variable. A) $33634816.3 B) $36634816.3 C) $34634816.3
35)
D) $37634816.3
SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. 36) A researcher asked 10 people how much they typically spend per month on movie entertainment.This table summarizes the results: 5.00 15.50 25.00 25.00 25.50 30.00 40.00 40.00 50.00 60.00 If we remove the low value of $5.00, how much does the median move by?
36)
37) Given this set of numbers x = {3, 7, 11, 13, 17, 19}, what is (x-5)2 ?
37)
38) For this data set {0.25, 0.762, 0.903, 1.254, 2.043, 3.162, 4.739, 10.162}, if the value of 10.162 is removed, how much does the mean reduce by? Round to 2 decimals.
38)
39) For a sample of 10 numbers, s2 = 29.16 and x2 = 1,015.2. What is the mean, rounding to 2 decimals.
39)
40) A researcher conducted a survey asking people how many times per year they recycle bottles. For the first 12 people, the average was 2.5 times per year. However, the thirteenth person said he recycles bottles every month. How much does the mean increase by? Round to 2 decimals.
40)
41) For a sample of 8 people visiting a store, they were asked to rate the store on a scale from 1 to 10, 1 = poor, 10 = excellent, as well as how much they spent on that visit: Rating 3 5 6 6 7 7 8 9 Spending 17.50 20.62 19.50 22.65 20.40 35.62 29.62 35.02 Using the Spearman rank correlation coefficient, what is the association between the two variables? Round to 2 decimals.
41)
42) Given this sample of data {6, 12, 17, 24, 27, 36, 102}, it would appear that 102 is an extreme value. If we remove it, what is the ratio of the original standard deviation to the new one? Round to 2 decimals.
42)
43) In a set of 10 numbers, 6 of them are 10, 16, 22, 28, 35 and 43. The remaining 4 values is the mode. If the mean of the 10 values is 25.4, what is the value of the mode?
43)
6
44) The coefficient of variation is defined as the ratio of the standard deviation to the mean for a set of data. For this sample of data {10.3, 12.7, 13.4, 16.6, 18.4, 19.2, 20.9, 25.4}, what is the coefficient of variation? Round to 2 decimals.
44)
45) A clothing store observed that its sales follow a bell curve with a mean of $185.62 and standard deviation of $24.50. What is the lowest sale they should expect about all the time?
45)
46) The Construction Association of BC reports the following data on the average construction completion time, in months: Average Construction Year time [months] 1980 46 1981 50 1982 55 1983 50 1984 40 1985 76 1986 82 1987 89 1988 90
46)
Compute the mean, mode, median and the standard deviation of the average construction completion time.
47) A class of 16 students had an average of 76% on a test. The lowest student mark was 6% and the highest was 100%. The trimmed mean is defined as the mean once the lowest and highest values are removed. For this test, what is the trimmed mean in percent? Round to 2 decimals.
47)
48) Given this data set {3.75, 6.42, 8.67, 10.903, 15.262, 17.606, 21.622, 29.005}, what is the eighty-second percentile if it is computed by hand? Round to 2 decimals.
48)
49) For a certain bell-curved distribution, the mean is 10.2 and the standard deviation is 25.6. For approximately 95% of the distribution, what is the highest value?
49)
50) The annual number of sick days taken by 15 employee is provided . Compute the mode of this data set. 12, 19, 21, 22, 23, 28, 6, 25, 13, 30 , 14, 30, 33, 26, 46
50)
51) A researcher wanted to measure the correlation between annual household income (in thousands of dollars) and weekly amount spent on groceries. For a sample of 7 households, these were the results: Income 25.2 36.7 45.5 58.2 69.6 72.8 84.7 Groceries 120 129 138 156 182 212 249 What is the correlation coefficient? Round to 2 decimals.
51)
52) Given this data set {5, 9, 14, 22, 35, 43, 54, 69}, what is the interquartile range if you compute the necessary percentiles by hand?
52)
7
TRUE/FALSE. Write 'T' if the statement is true and 'F' if the statement is false. 53) If the correlation coefficient for a set of x and y data is 0.925, this indicates a strong cause-and-effect relationship between the variables.
53)
54) For a set of data, the standard deviation would be smaller if the data set were a sample than if it were a population.
54)
55) You have a set of 10 numbers ranging from 5 to 60 with a median of 42.5 and mean of 30.6. If you add 46.7 to the data set, both the mean and standard deviation will increase.
55)
56) Suppose you had to assign ranks to this data set: {1, 3, 3, 3, 4, 4, 5, 6, 10}. The value of 4 would be assigned a rank of 5.
56)
57) In a data set with 16 numbers, if the average is 12.4 and you added 15.8 to the data set, the average would increase by 0.2.
57)
58) In a distribution that is bell curved, almost all the data is within 2 standard deviations of the mean.
58)
59) In a data set with 15 values, the IQR would be the difference between the twelfth and fourth values.
59)
60) If there is concern of extreme values in a set of x and y data, the Spearman rank correlation coefficient may be superior to the normal correlation coefficient.
60)
61) The standard deviation is the square root of the variance.
61)
62) The range is one measure of the degree of dispersion in a data set.
62)
63) An instructor collected the following data concerning students' performance on the final exam: Student A B C D Final exam mark 91 86 85 73 The instructor can assume the distribution of the final exam marks fits the normal distribution criteria, with a small degree of variance.The standard deviation of the final exam marks will be greater than 20.
63)
64) The coefficient of variation is the ratio of the standard deviation to the mean. If you have a data set and multiply all the values by 5, the coefficient of variation will also increase.
64)
65) You have a set of x and y data with r = 0.623. You remove one pair of data and now r = 0.895. This would indicate that the removed data pair were outliers.
65)
66) The correlation coefficient can be greatly affected by extreme values in the data.
66)
67) The Spearman rank correlation coefficient should only be used for linear data.
67)
8
68) An instructor collected the following data concerning students' performance on the final exam: Student A B C D Final exam mark 91 86 85 73 The instructor can assume the distribution of the final exam marks fits the normal distribution criteria, with a small degree of variance
68)
69) You have a data set in which the standard deviation is 8.3. If you add 10 to all the values in the set, the standard deviation increases to 18.3.
69)
70) If you have a data set ranging from 2 to 26 and you add -50 to the data set, the standard deviation will increase.
70)
71) If you have a data set of 10 numbers ranging from 10 to 52 and you add 26 to the data set, the standard deviation will increase.
71)
72) If you have a data set of 15 numbers ranging from 10 to 62 and you add 5 and 169 to the data set, the median would increase.
72)
73) In a data set, the average is affected more by extreme values than the median.
73)
74) You have a data set in which the standard deviation is 2.75. If all the values are multiplied by 8, the standard deviation increases to 22.
74)
75) In computing the standard deviation of either a population or a sample, the denominators in the formulas are the same.
75)
76) You have a set of 17 numbers in which the median is 18.3. If you remove the lowest and highest values, the median remains the same.
76)
9
Answer Key Testname: CHAPTER 3 1) C 2) C 3) A 4) B 5) A 6) C 7) A 8) D 9) C 10) A 11) B 12) C 13) D 14) C 15) A 16) C 17) D 18) D 19) D 20) A 21) C 22) D 23) C 24) C 25) B 26) A 27) A 28) B 29) D 30) B 31) A 32) B 33) D 34) C 35) C 36) 2.25 37) 448 38) 1.04 39) 8.68 40) 0.73 41) 0.72 42) 2.99 43) 25 44) 0.29 45) 112.12 46) 64.2, 50, 55, 19.8 47) 79.29 48) 24.43 49) 61.4 50) 30 10
Answer Key Testname: CHAPTER 3 51) 0.95 52) 41 53) FALSE 54) FALSE 55) FALSE 56) FALSE 57) TRUE 58) FALSE 59) TRUE 60) TRUE 61) TRUE 62) TRUE 63) FALSE 64) FALSE 65) TRUE 66) TRUE 67) FALSE 68) FALSE 69) FALSE 70) TRUE 71) FALSE 72) FALSE 73) TRUE 74) TRUE 75) FALSE 76) TRUE
11