AS RESEARCH METHODS
AS RESEARCH METHODS WORKBOOK
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Investigating People What do psychologists do? Psychologists try to explain human behaviour, we all have our own ideas and theories about why people do the things they do and behave in the way they do. For example, think about the students you did your GCSEs with, in your classes there would have been some students who nearly always got good marks and always seemed to be working hard, what is your explanation of why they behaved like this? Jot your theories in the box on next page.
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Reading the newspaper or watching the news we are often told that binge drinking among young people, especially young women is a growing problem in many cities, these reports often contain comments by journalists or “experts” to explain why this is happening. Do you think binge drinking is a real problem or do newspapers exaggerate the extent of binge drinking amongst young people? How would you investigate this? Why do you think young women may be drinking excessively? How could you find out if your theories are right? Jot down some of your ideas in the box
Psychologists develop theories and explanations of human behaviour and cognitive ability, they then have to demonstrate whether these ideas are true or not. Psychologist Elizabeth Loftus theorized that human memory of an event can be distorted and altered by the way questions are asked after an event, this has major implications for the accuracy of the testimony given by eye witnesses in court. Loftus demonstrated her theories were likely to be correct through a series of well designed experiments with the result that “leading questions” are no longer permitted in court. Research methods are the ways psychologists test their ideas and explanations, psychology is a science and all sciences are based on the findings of investigations. We learn lots of fascinating information about people when studying psychology but all of this information relies of the research carried out by psychologists. There are two main ways psychologists investigate human behaviour: Experimental Non- experimental Experiments basically involve “meddling with” or manipulating situations to find out how one factor (e.g. giving lots of praise) affects another factor (how well students perform in a AAFoster
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AS RESEARCH METHODS psychology test). The idea in experiments is that researchers keep some things the same (you used to call this a FAIR TEST, we’ll now refer to CONTROLS) while changing other factors and then measuring the results. Non-experimental methods include the following: Observational techniques – where you watch people and record their behaviour and information about them. Self report – this is where people tell you about themselves, through an interview or by filling in some sort of questionnaire Case study – where one person or a small group of people are studied very intensely and lots of information is gathered about them. Correlational analysis – where two pieces of information are collected than analysed to see if there is a relationship between them. Task: You may have heard the advice “eat five a day fruit and vegetables to be healthy”. Do you think eating 5 a day makes you healthier? With a partner design 5 short studies to investigate this claim using the methods outlined above. Present your ideas on sheets of A3 paper. KEY POINT: Psychology is the scientific study of human behaviour; psychologists have a wide range of methods for investigating behaviour. By the end of your AS course you will be able to describe all of these methods and assess their strengths and weaknesses.
The Experimental Method In an experiment the researcher is trying to find out whether a particular factor has an effect on a specific aspect of human behaviour or mental process. e.g. does giving children vitamin pills improve their IQ if women look at magazine pictures of models does it lower their self esteem does taking Prozac make people fell less depressed There are number of ways of conducting experiments each with their own strengths and weaknesses. You will have the opportunity to conduct a number of experiments to help you get to grips with the variations.
Laboratory experiments These are conducted in a special environment where variables can be carefully controlled. Participants are usually aware that they are taking part in an experiment although they may AAFoster
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AS RESEARCH METHODS not know the true aims of the study. Note: it doesn’t have to be a science lab, a room set aside for a psychology experiment would be classed as a “lab”.
Field Experiments An experiments conducted in a more natural environment, e.g. on a hospital ward. As with the laboratory experiment there is still deliberate manipulation of variables by the researcher but it is less likely that the participants know they are in an experiment. Task: read the example below of research that has been conducted and think about the following: Did the task appear artificial or contrived? Did the participants know they were being studied? Did the task resemble something people might do in their everyday life? Do you think it was a lab or field experiment? A: helping behaviour was investigated on a suburban street. A stooge got out of a car and dropped some books as a pedestrian approached. The stooge was either “low need” (able bodied) or “high need” (arm in a cast). Researchers found that the stooge wearing the cast received significantly more help. B: Psychologists wanted to investigate how to get people to stop smoking. Smokers were invited to a university and either shown a demonstration of a mechanical smoking machine or were shown a short frightening and graphic film about the effects of smoking. Both groups then filled in a questionnaire about their intention to stop smoking. Those in the film group were more likely to say they intended to give up. C: Nursery children were taken to a special room where there were lots of toys, including a 5ft inflatable toy (Bobo doll) and a mallet. A strange adult then came in and either played quietly with a selection of the toys OR began to hit the Bobo with the mallet. The children then had the opportunity to play alone with the toys. Those who saw the adult hitting the Bobo were far more likely to hit the Bobo than the children who hadn’t observed this. D: A group of pupils were given information about how their peers had done on a maths test. They were either told that their peers had done well or poorly on the test. They were later given a test in class, those who expected to do well did better than those who expected they would do poorly. In the box below give the strengths and weaknesses of lab experiments and field experiments
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Strengths: field
Weaknesses: field
HINTS: allocation of participants to groups, awareness of aims, control of extraneous variables, realism, replicability, expense and time, equipment and generalization.
Natural or Quasi Experiments In this situation, the independent variable is not being manipulated by the experimenter but is changing or occurring naturally in the environment. It may be the introduction of TV to a remote community for example. In this situation, the experimenter measures the effects (the DV) as a result of the naturally changing IV. Another example is an experiment examining the ability to recognize emotions from a photograph of a person’s eyes comparing people with autism to people who do not have autism. Having autism is naturally occurring; a psychologist cannot give participants autism.
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AS RESEARCH METHODS Strengths:
Weaknesses:
Experimental design There are occasions when it is possible to use the same people all the way through an experiment but under other circumstances this is not possible and separate groups of individuals need to be used. The way in which the subjects are ‘organised’ into groups is called the design of the experiment. Three experimental designs are commonly used: Independent groups: Testing separate groups of people. Each group is tested in a different condition. E.g. in an investigation into the effect of noise on ability to learn one group were given a speech to learn while the television was on and another group were given the same speech to learn in a silent room. The accuracy of their recital of the speech was compared .Repeated measures: Testing the same group of people in different conditions - the same people are used repeatedly. E.g. a group of participants was given a speech to learn while the television was on and were then tested on their recall, they were then given a speech to
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AS RESEARCH METHODS learn in a silent room and their performance compared with their first performance
Matched pairs: Testing separate groups of people - each member of one group is the same age, sex, or social background as a member of the other group. E.g. Hodges and Tizard wondered whether early institutionalization affects later social development, so each child who had spent the first 2 years of their life in an institution was matched with a comparison child of the same age, gender and social background who had grown up with their parents. Find out the meaning of the following terms that are important issues to consider in experimental design. Participant variables-
Order effects-
Practice effects-
Fatigue effects-
Counterbalance-
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AS RESEARCH METHODS Complete the table below summarising the advantages and disadvantages of various experimental designs.
Design
Advantages
Disadvantages
Repeated measures
Independent groups
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Remedy ( if any )
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Matched pairs
Questions 1. What is the difference between a control group and an experimental group?
2. What does it mean to say that a participant is randomly allocated to the various conditions in an experiment?
3. In what way does a repeated measures design differ from an independent measures (group) design?
4. Identify one disadvantage of the independent measures design.
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AS RESEARCH METHODS 5. Your teacher conducts an experiment in class. Each student is given a set of anagrams to solve and the time to solve each one is taken. You find that some of the anagrams were of nouns and others were of abstract words, in no particular order. a) What was the IV?
b) What design was this and what special precaution, associated with the design, has your teacher wisely taken and why?
6. Again your teacher conducts an experiment. Students are in pairs. You time your partner while she learns a finger maze, first with the left hand, then with the right. She then times while you learn first with the right, then with the left. a) What design is this?
b) What special precaution is taken and why?
Aims and Hypotheses Psychology is a science; it uses specific methods to test ideas about human behaviour and mental processes. Key terms: Aim – a general statement about the purpose of an investigation Hypothesis – a precise, testable statement about the expected outcome of the experiment.
Exercise 1 Read the following statements. Put an A by those that are aims and an H by those that are hypotheses. To investigate the relationship between food additives and hyperactive behaviour To find out whether playing Grand Theft Auto makes boys aggressive Boys who spend at least 2 hours a week playing Grand Theft Auto will score significantly higher on the “aggressive attitude” rating scale than boys who have never played Grand Theft Auto An investigation into alcohol consumption and reaction time AAFoster
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AS RESEARCH METHODS To investigate whether a greater number of words will be remembered if they are presented in an organised way (e.g. alphabetically) than if they are listed randomly. More about hypotheses What’s the difference between these two hypotheses? Participants who read digits aloud will later recall a greater number of digits than participants who read the digits sub-vocally. There will be no difference between the number of digits recalled by participants who read them out loud and those who read them sub-vocally. One is a Research Hypothesis, one is a Null Hypothesis. In the space below write your own definitions of both of these hypotheses.
Research hypotheses state results are not due to chance and are significant in supporting the idea being investigated, the null hypothesis states results a fluke, or more correctly, are due to chance factors. Just to confuse you the research hypothesis may be referred to by two other names. Find them out and write them below. In the table below there is list of hypotheses. Write an N or an H beside them to show if they are the Null or the Experimental. If it is a Null rewrite it as an Experimental in the space opposite and vice versa. Null or experimental hypothesis? Whether or not a person has committed murder will have no affect on measurement of activity in the frontal lobes of the brain Participants who are instructed to semantically process words will recall more words than participants who are instructed to visually process words. There will be no difference in the number of trigrams recalled after 18 seconds compared to the number recalled after 3 seconds.
Hypothesis rewritten as N or H
The number of trials a person has on the Stroop test will not affect their performance There will be a difference in the number of French words retained after one year between participants who learned over spaced lesson AAFoster
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AS RESEARCH METHODS compared to participants who learned in intensive sessions Fathers and mothers differ in the amount of physical play they engage in with their children Facial hair has no effect on estimates of age in men
Does your cat have 1 tail or 2? Read these 4 hypotheses. What do the first two have in common, how are the last two different? Participants who read digits aloud will later recall a greater number of digits than participants who read the digits sub-vocally. Children who spend the first two years of their lives in an institution will be rated less popular by their peers than children who spend the first two years of their lives in a family setting. There will be a difference in the number of digits recalled in the reading aloud condition compared to the sub-vocal condition. There will be a difference in the popularity ratings by peers between children who spent the first two years of their lives in an institution and children who spent them in a family setting. These two types of hypothesis are called one tailed and two tailed, or directional and nondirectional. Write your own definition of both types in the space below.
Operationalising Variables – sounds complicated, but is very straightforward. Operationalising just means making something clear or unambiguous. Operationalising a variable is the process of devising a clear way of measuring something so that another person knows exactly what you have done. Compare these two hypotheses: Students learn better earlier in the day. AAFoster
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AS RESEARCH METHODS VS Students will correctly recall more words out of a possible 20 when they are tested at 9.00am than when they are given the same test at 2.00pm. Here are some variables that psychologists might investigate. Try to make then clear and measurable, i.e. OPERATIONALISE them. 1. 2. 3. 4.
Girls do better at school than boys Alcohol increases reaction time Short words are more easily remembered than long words The amount of sleep you have affects your memory
Variables – quite simply the things we measure or manipulate in psychology An experiment is a study of cause and effect; it involves the deliberate manipulation of one factor or variable, while trying to keep all other variables constant. In a psychology experiment we try to keep all aspects of the situation constant except for the one being looked at. The aspect that is varied is called the Independent variable (IV). This is the one that the experimenter manipulates – it is assumed to have a direct effect on the ……. Dependent variable or DV. This is the factor or variable that the experimenter measures. Some variables, however much we try, cannot be kept constant and these are known as extraneous or confounding variables. They might be important enough to provide alternative explanations for the effects. REMINDER: The IV is the variable that we know at the beginning of the experiment, the DV is the one we find out.
Exercise A psychologist investigates the effect of caffeine on reaction time. One group of participants are given a cup of coffee containing 10mg of caffeine, the other group are given a cup with 2 mg of caffeine. Participants then had a task where they had to click on a moving target on a computer screen; the psychologist measured how many seconds it took each participant to click on the target. The first group was tested at 9am on a bright sunny morning; the second group was tested at 3pm on the same day with the rain hammering on the windows of the testing room. AAFoster
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AS RESEARCH METHODS 1. What was the IV? 2. What was the DV? 3. List all the potential extraneous or confounding variables in this experiment.
Exercise -For the following hypotheses, give the IV and the DV and state whether it is a one or two tailed hypothesis.
Drug A affects memory IV DV 1 or 2 tailed
Bulls will charge more often when presented with a red rag than a blue rag. IV DV 1 or 2 tailed
Social class affects IQ scores IV DV 1 or 2 tailed
First children learn to speak earlier than second children IV DV 1 or 2 tailed
Self reports Questionnaires and Interviews A questionnaire is a set of written questions that can be answered easily: it is especially useful in gathering information from large numbers of people. To produce accurate results, a questionnaire must be worded with extreme care. The construction of a reliable questionnaire is a difficult task because even the slightest change in the way the questions are worded can distort the results. AAFoster
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AS RESEARCH METHODS In a survey, research information is collected from as sample of people who are said to be representative of the larger population. There are many types of questions that can go into a questionnaire. In the table below write the type of question from the list below by the question. open questions closed questions forced choice questions likert scale questions Question
Question type
Which of the following factors make you stressed at work? (tick all that apply) Noise at work□ Too much to do□ Lack of control□ Workmates□ How many hours a week do you work □0 □ less than 15 □between 16 and 34 □35 or more What do you enjoy most about your job? Which statement do you most agree with? A: It is most important to have a good salary B: it is most important to enjoy your work Work is stressful. Strongly agree 1. Agree 2. Not sure AAFoster
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AS RESEARCH METHODS 3. Disagree 4. Strongly disagree
Evaluating Questionnaires What are the advantages of using closed questions (fixed choice of answers)?
What are the advantages of using open questions (space to write any answer) for more detailed individual answers?
What are the disadvantages of using closed questions (fixed choice of answers)?
What are the disadvantages of using open questions (space to write any answer) for more detailed individual answers?
Self reports have a few strengths and weaknesses. Consider the following words and phrases to draw up a table of strengths and weakness. Look up unfamiliar terms.
Social desirability bias Quantitative data Ease of analysis Collect large amounts of data Untruthfulness Convenience Low response rate Interpretation Show attitude changes
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AS RESEARCH METHODS Strengths:
Weaknesses:
Questions 1. Why is it important to researchers using the survey method that their sample is representative of the population they are studying?
2. What advantage do questionnaires have over the interview method of conducting surveys?
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AS RESEARCH METHODS 3. What is the principal advantage of the survey as a method of collecting data over the laboratory experiment?
4. What element of the survey method is most likely to introduce unreliability?
5. Why might people not answer truthfully on a questionnaire?
Interviews Interviews are face-to-face conversations (sometimes interviews are conducted over the phone), these can be unstructured, apparently informal chats, or they can be formal, structured interviews with pre-determined questions, for example, clinical tests used in psychiatry. Interviews can be recorded for later, in-depth analysis. Strengths and weaknesses of interviews: Ideas: qualitative data, ease of analysis?, standardized? time consuming, individual’s point of view, detailed information, interviewer effects, likeable/attractive/unattractive interviewer, truthfulness
Strengths:
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Observational Methods In many cases, psychologists simply observe the actual behaviour of people in various kinds of situations. In everyday life, we tend to make subjective observations i.e. we let our own personal feelings and experiences affect what we see. Psychologists try to make observations in a more disciplined manner. They try to describe behaviour objectively and exactly.
In order to do this it is necessary
For all observers involved in the same research operation to have a clear idea of exactly what they are observing [this improves inter-observer or inter-rater reliability ] To use a system for categorizing and recording information To us more than one observer
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AS RESEARCH METHODS INTER-OBSERVER RELIABILITY: the extent to which there is agreement between two or more observers involved in observations of behaviour. A good study should have at least 80% agreement between observers. RELIABILITY: in psychology this means consistency and replicability. Any measuring tool, e.g. a ruler, personality test or observations made by two observers of the same person should give replicable trustworthy results. If a “tool” is measuring the same thing it should produce the same result every time, if the result is different we need to be sure that it is the thing we are measuring that has changed (e.g. personality or ability) and not a fault in our measuring tool. Strict and controlled experimental procedures make it easier to replicate work to see if findings are reliable. Example: in class we did an observation of public speaking behaviour. What were some of the categories of behaviour and what behaviours were coded in each category?
Observational studies may be:
Non –participant Participant
In participant observation the observer acts as part of the group being watched, e.g. Zimbardo’s prison study, Piliaven’s subway Samaritan’s study or Rosenhan’s study of psychiatric hospitals. In non participant observation the experimenter does not become part of the group being observed. Observations may also be NATURALISTIC where behavior is studied in a natural situation where everything has been left as it is normally (e.g. observing boys and girls playing on a playground) or CONTROLLED where some variables are controlled and manipulated by the experimenter reducing the “naturalness” of the behavior being studied, e.g. Bandura’s experiment where children were exposed to an adult model playing with certain toys and were later observed playing with the same toys to see if they imitated the adult. When designing all observations, psychologists need to be systematic however observations may be either structured or unstructured. Structured observation involves the use of tables of pre-determined categories of behaviour and systematic sampling. There are 3 ways of sampling behaviour in structured observational studies:
Time sampling: Observations may be made at regular time intervals and coded. Event sampling: Keep a tally chart of each time a type of behaviour occurs. Point sampling: Focus on one individual at a time for set period of time.
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AS RESEARCH METHODS Unstructured observations are when the observer records everything that happens. It may be difficult to avoid bias by focusing on what you want or expect to see happening, in theory all observations are noted as anything could prove to be important. In this case the observer may use a diary method to record events, feelings, or moods or perhaps a video recording. This is useful as behaviour may be analysed in more detail later.
Strengths and weaknesses of observations Write S by the statements that are strengths and W by those that are weaknesses.
Strength or Weakness
Observer may affect behaviour if detected.
Studying of animals that cannot be observed in captivity.
More natural behaviour occurs if people are unaware of observation.
Need for more than one observer
Difficult to replicate - cannot control extraneous variables.
Study of situations that cannot be artificially set up.
Questions 1. What name is given to the type of observation in which a researcher observes behaviour in its natural environment and does not attempt to interfere with what is being observed? 2. What is observer bias? AAFoster
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AS RESEARCH METHODS 3. What is meant by the term inter-observer reliability? 4. What ethical issue is raised by participant observation?
Task A group of students decided to study student behavior in the school library a) b) c) d) e) f) g)
Suggest one or more hypotheses that you might investigate. List 5 behaviours you might include in a behavior checklist. Identify a suitable sampling procedure and explain how you would do it. How could you observe the students so that they were not aware of being watched? What ethical issues might be raised in this observational study? How would you deal with these issues? Explain in what way this would be a naturalistic observation.
Case Studies
A case study involves a detailed investigation of a single individual or small group of individuals. Example of the type of research that would lend itself to a case study are investigations into the effects of a stroke on later personality and behaviour, studying the effects of severe deprivation and the possibilities for recovery and so on. Case studies often involve the use of interviews with the individual and family, friends, medical professionals etc. They may continue for many years and for this reason are often expensive and time consuming. However, the may lead to the way to future research. Case studies of people with rare or unusual illnesses or abilities are often turned into TV documentaries. The BBC series by Professor Robert Winston “Child of Our Time� is based on a detailed study of a number of children from varying backgrounds born in the year 2000. Using a variety of textbooks and information on resources find out what the strengths and weaknesses of case studies are.
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Strengths:
Weaknesses:
Correlation Sometimes psychologists are interested in whether there is a relationship between two factors or variables, e.g. is there a relationship between how extrovert you are and how good at maths you are. A correlation is a statistical technique used to measure or quantify the strength of relationship between two variables. It investigates whether people, for example, high or low on one measure also tend to be correspondingly high or low on a second measure.
Analysis of correlation
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AS RESEARCH METHODS For a correlational study, the data can be plotted as points on a scattergraph. A line of best fit is then drawn through the points to show the trend of the data. If both variables increase together, this is a positive correlation. When the correlation coefficient is calculated it is between 0 - +1, the nearer the value is to +1, the stronger the relationship.
If one variable increases as other decreases this is a negative correlation. When the correlation coefficient is calculated it is between 0 - －1, the nearer the value is to －1, the stronger the relationship.
If no line of best fit can be drawn, there is no correlation. In real life human situations, or psychology experiments you will not find perfect correlation between variables, life is just like that. Strengths and weaknesses of correlation – fill in the table below using all the resources available
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Questions 1. What is the purpose of the correlation as an investigative tool?
2. What does it mean to say that two variables are correlated?
3. What value would the correlation coefficient have for a perfect negative correlation?
4. Under what conditions would a correlational study be most useful?
5. What is the major weakness of correlational studies compared to experimental ones?
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AS RESEARCH METHODS Selection of participants OK, so you’ve thought up this brilliant psychological experiment and designed it perfectly. But who are you going to try it out on? In order to conduct any research we need some people or animals to study. The participants (or subjects) which are to be used are called a sample. To obtain sample researchers must first identify the target population. This is the whole group with which the study is concerned. Psychologists try not to use a biased sample -that is a sample that is not representative. There are several ways to choose a sample from a target population Random sampling
Here every member of the target population has the same chance of appearing in the sample. It could be done by drawing straws or pulling names from a hat. One popular method is to give each member of the target population a number and then to take numbers from a random number table.
Systematic sampling Here every 4th or 10th (or any other number) name is taken from a list of the target population. Stratified sampling In this case the sample must contain representatives of all the groups that appear in the target population in the same proportion, in the sample, as they are in the target. E.g. if you were looking at the attitudes of Imberhorne pupils to learning languages you should take the same proportion of students from each year group. Opportunity sampling This is not a very good method of sampling since it can provide a biased sample but it is a commonly used one. In this case, the researcher uses whoever is available at the time. All too often researchers claim to have a random sample when what they actually did was stop and question whoever walked near them! Self-selected samples In this case, participants chose themselves by, for example answering an advertisement in a newspaper or replying to a postal questionnaire. This is not a representative sample since AAFoster
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AS RESEARCH METHODS most people do not volunteer or return a questionnaire! Those who do so are hardly likely to be representative of the target population.
What is BIAS? Biased simply means distorted in some way so we don’t get a clear reflection of the attitude or behaviour being studied, like looking in a wobbly mirror. There are many types of bias such as experimenter bias, social desirability bias, observer bias, interviewer bias or sample bias. Activity How random is random? names and 20 girls’ names.
Take 40 pieces of paper and write 20 boys’
Put them in a hat and draw out 10 slips of paper. If the selection is unbiased, you ideally should get 5 boys and 5 girls. Put the slips of paper back and draw 10 out again. Repeat this a total of 4 times and then try it with a larger sample. Each time, record how many boys’ and girls’ names were drawn.
The point is that, in principle, random selection results in an unbiased and representative sample, but only if the sample is large enough. Is this what you found? What happens if you put 40 boys’ names and 20 girls’ names in the hat? How does the sampling method affect the sample of participants? Task: Getting a sample of year 12 students to survey about their initial impressions of sixth from life.
Write down the names of the first 20 year 12 students you can think of. You’ve been provided with a list of all students, starting at the top write down the names of every tenth student until you have 20. Cut up your list of names, put each name in a hat and draw out 20.
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AS RESEARCH METHODS What type of sampling method have you used in each case? Compare the sample obtained with each method, think about gender, subjects studied, personality and interests of the students. What type of sampling method has been used in each of these examples? 1. A researcher wished to study memory in children aged between 5 and 11. He contacted the headmaster of a local primary school and arranged to test the children in school. 2. A university department undertook a study of mobile phone use in adolescents, using a questionnaire. The questionnaire was given to a group of students in a local comprehensive school, selected by placing all the students’ names in a container and drawing out 50 names. 3. A class of psychology students conducts a study on memory. They put a notice on the sixth form notice board asking for students who have an hour to spare.
Evaluating samples Sampling method
strengths
weaknesses
Opportunity
Self selected
Random
Systematic
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Questions 1. What is the target population in the following studies? a. A study of attitudes of social democrat voters to NHS reform b. Research into a cure for fear of spiders c. An experiment to investigate the effects of separation in infant monkeys d. A study of prejudice amongst white South Africans e. Research into the use of specially adapted cookers for blind people 2. Define the term random sample 3. Why are self-selected samples never representative? 4. Outline the main factors governing the size of the sample psychologists use.
Relationships between researchers and participants This does not mean becoming emotionally involved and going out with participants! What it does mean is ways in which either the researcher or the participants can influence the results this is known as "causing bias". Researcher effects This is sometimes known as Experimenter Bias. In this situation, the researcher can affect the behaviour of the participants, thus affecting the results of the study. For example:
The researcher might unwittingly communicate his expectations to the participants. This could happen through only small changes in body language or tone of voice. Or it can be in the interpretation of data, a researcher may read into things more of what he or she would like to find! An attractive researcher might affect participant responses. For example, male researchers smile at female participants more than they do at male ones!
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Even rats learned mazes faster when expected to! (Rosenthal, 1966) Just the presence of the researcher can affect participant behaviour, more so if the researcher is filming people.
Demand characteristics Participants can also affect results! They might read things into the situation and start changing their behaviour responding to the perceived demands of the study. They might feel that they are helping the experimenter - or, they may not like the experimenter. Demand characteristics can occur in the following situations:
Participants may worry about being in a psychological study and want to appear ‘normal’, this may change their behaviour. Participants may try to guess what the investigation is about then behave in the way they think the investigator wants them to. On the other hand, they may deliberately try to behave in an unexpected way. (Unofficially known as the "stuff you effect"). Participants might just try to ‘look good’ (social desirability) and behave out of character or not tell the truth. This can be a problem for questionnaires on sensitive issues.
How can psychologists minimise researcher effects and demand characteristics? There are several things a researcher can do:
Disguise the purpose of the investigation: There is some deception in many psychological studies to stop participants guessing the aims and changing their behaviour. Participants in Milgram’s obedience studies thought it was a study on effects of punishment on learning and memory. All the studies below are liable to be affected by demand characteristics and experimenter bias. In each case say how these effects are likely to be shown.
Possible demand characteristics
a. The cleaning contract at a local school is privatised. After 6 months, the teaching staff are asked to assess the standard of cleanliness. Is it better, the same or worse? AAFoster
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Possible sources of experimenter bias
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b. A group of students is interviewed about their belief in superstitions. The aim of the study is to see if there is a difference between males and females in the degree to which they are superstitious.
c. An experimenter observes the amount of eye-contact between two people who have been requested to have a staged argument as compared to the amount of eye-contact between two people asked to have an ordinary conversation.
Data There are three types of data, or ‘levels of measurement’ that can be collected Nominal. This is where simple categories are used, for example we can categorise people as smokers or non-smokers, male or female, left brain dominant vs. right brain dominant. A numerical value often cannot be assigned to these categories, you either are or aren’t a smoker! With nominal data you will usually count up frequencies of an occurrence to place into categories, e.g. number of women who comply with medical advice, number of men who comply. Examples of nominal data
If you are placing data in a tally chart, this would be nominal data
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If you are counting the no of times something has happened, this is nominal data e.g. no of men stopping for a pedestrian a t a zebra crossing, number of women; no of times someone smiles in a body language observation etc
If you are placing people into categories of high, medium and low this is nominal data. E.G Categories might be left brain vs. right brain dominant, and high, medium and low in creativity.
Ordinal Data This is data where a numerical value is used, but is based on ranks or ratings. For example doctors at a practice may be ranked in preference by patients, first choice, second choice etc. Alternatively drs may be rated on how satisfied pts are by their treatment, from very high satisfaction to very low. Note ordinal data is very subjective as it is based on a person’s own personal opinion, which may or may not be accurate.
Examples of ordinal data Use of self report questionnaire with a rating scale would be ordinal data. The likert scale is the most commonly used scale, where Ps are given a statement and asked to state level of agreement, form ‘agree very much’ to ‘disagree very much’ Asking Ps to express a preference by ranking is ordinal data Interval data This is where data is in the form of equal units e.g. score on an objective test. In such a case, if one P has scored 20 on a test and another has only scored 10, we would be correct in saying the first person has performed twice as well as the second. This would not be the case with ordinal data – if rating physical attractiveness, a person with a score of 10 out of 10 wouldn’t be exactly twice as attractive as a person with a score of 5 out of 10 – the units are not equal here. Note interval data is objective – based on facts, not opinions and ordinal data is subjective as it based on a person’s own personal opinion which may or may not be correct. Note data is only interval data if items are of similar level of difficulty. Ratio data is interval data with an absolute value of zero, e.g. distance or speed. Note below whether you think data is nominal, ordinal or interval:
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AS RESEARCH METHODS Judges’ marks for paintings in an art competition _____________________ Patients medical conditions are classified as acute, chronic or not yet classified ______________ Ps are observed and grouped as being either friendly or unfriendly _____________ Ps reaction times to a buzzer (they have to hit a button as soon as the buzzer goes off) ____________________________ Scores on a memory test in which the words they are recalling are of varying level of difficulty (some are everyday words some are unusual) ____________________________ When psychologists have carried out their research they end up with a set of raw data. This data is the results of their research that they must then make sense of. This can be done in a number of ways depending on the data collected.
Raw data tables These do not tell us anything very much until they are organised and summarised in a suitable way. Number of words recalled with and without noise
Word recall with noise
Word recall without noise
10
16
12
14
11
15
10
14
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AS RESEARCH METHODS Summary tables are those that summarise data to give more meaningful results. For example, these might give an idea of what numbers are typical and how widely spread the numbers are. Looking for typical or representative values (i.e. average) can be done by looking at the mode, median or mean. The mean score is the score commonly known as an average, and the one you are most likely to use. Sometimes the mean is affected by exceptional scores (called outliers) either way above or way below average, (and sometimes these are discarded by psychologists for obvious reasons!). Looking for the spread of numbers may also be helpful.. You are most likely to use range which is the lowest to the highest scores e.g. 10 – 16 gives a range of 6. Draw up a summary table for the data given at the top of this page.
Quantitative and Qualitative data Numerical data is called quantitative data, it is easy to compare and analyse and find patterns in. Data that can’t be reduced to numbers and has lots of detail is called qualitative data. Qualitative description A psychologist uses qualitative description for two reasons: 1. To write about qualitative observations made during the experiment, incidental perhaps – how people responded to types of questions etc. 2. Sometimes data is qualitative – an interview, for example, that draws out possible reasons why a phenomenon may occur.
Type of data quantitative
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qualitative
Questions 1.Milgram produced both quantitative and qualitative data in his study of obedience. When you have studied his research make a note in the space below of an example of both types of data in this study.
2. What type of data did Loftus and Palmer use?
3 . Give examples of both quantitative and qualitative data in the studies and Rosenhan and Thigpen and Cleckley.
Test you understanding- Using different methods.
Psychologists may use different methods to answer different questions about a topic. Suppose you are a psychologist interested in aggression. Which method would be most appropriated to study the following aspects of aggressive behaviour?
Aim
Method
1. To see if there is a difference in the amount of aggression shown by the following pairs of sex year olds ; two boys; two girls; a girl and a boy
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2. To examine the relationship between aggression and TV viewing
3. To find out if children in a playground are aggressive towards each other
4. To understand the factors which contributed to the development of aggressive behaviour in a man who is persistently extremely violent towards his family
5. To compare the attitudes of young and older parents towards the use of physical punishment in schools
6. To compare physiological changes that occur in people watching violent films using a control group who watch non-violent films
Factors related to good design The following factors are important for psychologists to consider when designing an investigation:
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Often psychologists carry out a ‘dress rehearsal’ of their study before they go out into the world and conduct the research on a large number of people. This is called doing a pilot study. This enables the researcher to check for design faults. This is a routine procedure especially used when carrying out research using questionnaires. It is very important for psychologists to be sure that their research is producing reliable results. Reliability refers to the consistency of results – in science this might mean how accurate is a ruler at measuring or how good is a calculator at adding up? In psychology it means would a test marked by two different people, be scored in an identical way? Or, if a study is replicated would the findings should be similar?
Reliability, on its own, is not enough. Studies should be measuring what they are intended to measure. If a researcher wanted to measure IQ would he do it with a ruler? Validity refers to whether or not a test measures what it was designed to measure. For example, do IQ tests really measure ‘intelligence’ or do they measure performance on the test? There are many different forms of reliability and validity which researchers need to be concerned with. The main ones are shown below : Forms of reliability Scorer reliability – how closely different people who are marking a test or performance agree with each other Test-retest reliability – if participants take the same test twice, would they get similar results Forms of validity Internal validity - the extent to which study is free of design faults, which may affect results. Ecological validity this is a type of ‘external validity’. This means the extent to which generalisation can be made from the test environment to other situations. Face validity – does the test LOOK like it is measuring what it is supposed to be measuring? Questions 1. What is meant by the term reliability in psychology? 2. Identify the three main types of validity. 3. Write a sentence to explain validity in your own words
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Activity
An experiment: Learning a foreign language
than others?
How easy is it to learn words in a foreign language? Are some people better at this
Work with a partner. Take turns to read the words listed below out loud to your partner. Some words are repeated to help you learn them. Say each word clearly to your partner. iktitaf
afworbu
saricik
zabulon
afworbu
biwojni
afworbu
iktitaf
iktitaf
saricik
iktitaf
afworbu
biwojni
nansoma
dilikli
iktitaf
nansoma
dilikli
afworbu
biwojni
afworbu
kadirga
afworbu
iktitaf
enanwal
afworbu
biwojni
iktitaf
iktitaf
saricik
iktitaf
iktitaf
iktitaf
biwojni
biwojni
afworbu
saricik
kadirga
afworbu
iktitaf
afworbu
lokanta
afworbu
iktitaf
saricik
afworbu
iktitaf
iktitaf
nansoma
biwojni
iktitaf
saricik
biwojni
afworbu
afworbu
afworbu
enanwal
iktitaf
saricik
nansoma
iktitaf
iktitaf
afworbu
iktitaf
afworbu
iktitaf
afworbu
nansoma
biwojni
saricik
iktitaf
afworbu
kadirga
afworbu
iktitaf
afworbu
kadirga
iktitaf
afworbu
saricik
afworbu
kadirga
saricik
biwojni
For each of the words listed in the table decide how ‘nice’ the word was. Give the word a rating between 1 and 5 where 5 represents a word that sounded very pleasant whereas 1 is for a word that didn’t sound very pleasant. Own results afworbu biwojni civadra dilikli enanwal iktitaf jandara kadirga lokanta nansoma saricik zabulon
favourability rating (score between 1 and 5)
Class averages
Mean favourability rating (score between 1 and 5)
afworbu biwojni civadra dilikli enanwal iktitaf jandara kadirga lokanta nansoma saricik zabulon
Which word was rated as nicest, which had the lowest nice score? AAFoster
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AS RESEARCH METHODS How do your own results compare to the class averages? Iktitaf and afworbu both appeared 24 times, saricik and biwojni (both 10 times), nansoma and kadirga (5 times each), enanwal and dilikli (twice), zabulon and lokanta (once) and jandara and civadra (not at all). Zajonc (1968) suggested that familiarity doesn’t breed contempt – we like things because they are familiar. He called this the mere exposure effect. Qs 1. What was the IV? 2. What was the DV? 3. What were the aims of this experiment? 4. Did you guess what the aims of the experiment were? 5. Draw a bar chart to show your class findings. High frequency words: iktitaf, afworbu, saricik, biwojni, nansoma and kadirga. Low frequency words: enanwal, dilikli, zabulon, lokanta, jandara and civadra. Activity
Memory and organisation
A favourite experiment for students is one that concerns organisation and memory. If words are presented to a participant organised in categories, they are more easily memorised than if they are presented in a random order list. Organised list
Random list
Dogs – Labrador, beagle, boxer, spaniel
Pear, beagle, clarinet hail, rain, drinks, rose, squash, hand,
Fruit – apple, pear, plum, orange
boxer, iron, coke, gold, harp, piano, metal apple, body, fruit, instruments, daffodil, plum, nose, weather, copper Labrador,
Weather –snow, rain, sleet, hail Instruments – harp, piano, flute, clarinet
water, flowers, brass, foot, tulips, pansy, dogs, sleet, milk, orange, toes, snow, flute, spaniel
Drinks- water, milk, squash, coke Body – nose, toes, foot, hand Metal – brass, iron, gold, copper
Using the word list given design and carry out an experiment to investigate organisation and memory. 1. Write a hypothesis 2. Operationalise your variables 3. Choose your design (RM/IM) 4. Explain your design choice highlighting the advantages and disadvantages 5. Suggest ways to overcome the disadvantages AAFoster
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AS RESEARCH METHODS 6. Decide how you would select your participants 7. Identify the advantages and disadvantages of your choice 8. Suggest how you display your data. After you have carried it out: Display your results using appropriate visual displays and written form Give simple conclusions
Activity
Primacy and recency effects
Cognitive psychologists are interested in a phenomenon called the primacy/recency effect, which states that when we are presented a large block of information we are most likely to remember a larger proportion of the first part and the last part presented to us. In pairs design an experiment to test this! Who will your participants be? What sampling method are you going to use? What stimulus material will you give to your participants? (e.g. list of words, facts, number etc.) How are you to test their recall? What design will you use? What are the benefits of this design? What are the limitations of this design? How else could you measure the DV? Some hints and ideas for measuring recall Free recall – participants list all the items they can remember without any cues Cued recall – participants are given some clues, e.g. first letter of word Recognition test – participants choose correct items from a large list or from multiple choices Think about how and why results would differ using each method.
Get thinking… Study A – In order to study the effects of sleep deprivation, students are asked to limit their sleep to five hours a night for three nights and then sleep normally for the next three nights. Each day the student’s cognitive abilities are assessed using a memory test. Study B – Participants volunteer to take part in a study. They are told the study is about public speaking but the real aim is to see how people respond to encouragement by others. Some participants speak in front of a group of people who smile at them, while others talk to a group who appear disinterested.
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AS RESEARCH METHODS Study C – Marathon runners are assessed on how much sleep they have the night before and the night after a race to see what the effects of exercise are on sleep. Study D – A teacher is doing a psychology course and decides to try a little experiment with her class of eight year olds. She gives half the class a test in the morning and half of them do the same test in the afternoon to see if time of day affects performance. For each study, answer the following questions:1. Identify the IV and the DV. 2. How could you operationalise the IV and the DV? 3. Identify one possible extraneous variable. 4. In what way is this study high or low in validity? 5. Identify at least two possible ethical issues. 6. Describe how you would deal with each ethical issue.
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