A2 exams - Research methods questions Detailed feedback from the Report on the Examination The A2 Examination: January 2010 exam Unit 4 Topic: Media Psychology Psychology in action includes research methods 4 (a) ‘Content analysis has shown that many video games have violent questions. themes. Many of these games are aimed at adolescents. There is a growing concern that such games encourage violent behaviour in (a) (i) marked with young people who play them.’ AO2/AO3 criteria. (i) Explain some of the difficulties of conducting research into the effects of playing games. (5 marks) (ii) Discuss what psychological research has told us about some of the effects of video games on young people (5 marks + 5 marks) (b) Describe how social psychology explains the attraction of celebrity. (4 marks + 6 marks) (a) (ii) and (b) students omitted evaluation. The A2 Examination: January 2010 exam Unit 4 Topic: The Psychology of Addictive Behaviour Part (b) doesn’t have to relate to smoking. 5 (a) A large survey on behalf of the Gambling Commission provided a number of interesting findings about gambling behaviour in Great Britain. For example, 57% of the population had gambled on the Discussed National Lottery Draw in 2007, although the rate of problem gambling addiction in in the adult population was only about 0.6%. general rather (i) Explain some of the difficulties of gathering data about problem than gambling. gambling. (5 marks) (b) Many (ii) Outline and evaluate one explanation of gambling addiction. (4 discussed marks + 6 marks) maintenance (b) 'The relapse rate for smokers in the first three months after trying rather than to give up is estimated at 70%.’ relapse. Some didn’t do any Discuss reasons why relapse occurs in people with addictive evaluation. behaviour. (5 marks + 5 marks) The A2 Examination: January 2010 exam Unit 4 Topic: Anomalistic Psychology 6 (a) A researcher wanted to test the ability of a known ‘psychic healer’. Ten volunteers suffering from chronic back pain were selected through newspaper adverts. The volunteers were all given a questionnaire which rated their belief in psychic healing and another questionnaire which rated their levels of pain. They were then randomly assigned to either a treatment or a control group. Afterwards all the volunteers filled in the pain questionnaire again. The researcher found that there was no significant effect on pain relief as a result of psychic healing. Answer the following questions, using your knowledge about research into psychic healing. (i) The researcher wanted to know whether there was a correlation between belief in psychic healing and improvement in pain ratings. What statistical test could the researcher use? Justify your answer. (2 marks) (ii) Outline one ethical issue in this study and suggest how the researcher could have dealt with it. (3 marks) (iii) ‘It is interesting why, even today in the modern age of science and technology, some people still believe in psychic healing’. Discuss factors underlying belief in psychic healing. (5 marks + 5 marks) (b) Outline and evaluate psychological research into belief in out-ofbody experiences and/or near-death experiences. (4 marks + 6 marks) A number of centres had mainly anecdotal answers. (a) (ii) Often gave only brief method of dealing with ethical issue. (a) (iii) Candidates often ignored ‘underlying factors’ and just discussed research on psychic healing. The A2 Examination: January 2010 exam Unit 4 Topic: Research methods A psychologist was interested in testing a new treatment for people with eating disorders. She put adverts in several London clinics to recruit participants. Thirty people cam forward and they were all given a structured interview by a trained therapist. The therapist then calculated a numerical score for each participant as a measure of their current functioning, where 50 indicates excellent, healthy functioning and zero indicates failure to function adequately. The psychologist then randomly allocated half the participants to a treatment group and half to a no-treatment group. After eight weeks, each participant was re-assessed using a structured interview conducted by the same trained therapist, and given a new numerical score. The therapist did not know which participants had been in either group. For each participant, the psychologist calculated an improvement score by subtracting the score at the start of the study from the score after eight weeks. The greater the number, the better the improvement. Table 1: Median and range of improvement scores for the treatment and notreatment group Treatment group No-treatment group Median 10.9 2.7 Range 2.1 0.8 The A2 Examination: January 2010 exam Unit 4 (a) With reference to the data in Table 1, outline what the findings of this investigation seem to show about the effectiveness of the treatment. (2 marks) Some confused by median and range. (b) The psychologist used a statistical test to find out whether there was a significant difference in improvement between the ‘treatment’ and ‘no-treatment’ groups. She found a significant difference at the 5% level for a one-tailed test (p ≤ 0.05) Some just wrote ‘Spearman’s rho because it is nominal data and repeated measures’. Identify an appropriate statistical test for analysing participants’ scores. Explain why it would be a suitable test to use in this study. (4 marks) (c) What is the likelihood of the psychologist having made a Type 1 error in this study? Explain your answer. (2 marks) Some knew the definition but couldn’t apply it. (d) The psychologist assumed that improvements in the treatment group were a direct result of the new type of treatment. Suggest two other reasons why people in the treatment group might have improved. (4 marks) Some answers lacked detail, and some gave two answers essentially the same. The A2 Examination: January 2010 exam Unit 4 (e) The psychologist could have used selfreport questionnaires to assess the participants instead of using interviews with the therapist. Explain one advantage and one disadvantage of using self-report questionnaires in this study rather than interviews. (4 marks) (f) The psychologist needed to obtain informed consent from her participants. Write a brief consent form which would be suitable for this study. You should include some details of what participants could expect to happen in the study and how they would be protected. (5 marks) (g) What is meant by reliability? Explain how the reliability of the scores in this study could be checked. (4 marks) Many missed the point that the comparison had to be made with interviews, so e.g. social desirability is not creditworthy. Some candidates saw it as a legal disclaimer (you can’t sue us). Poor expression and clarity lost marks for some. Muddled answers e.g. ‘if you do the study again you will get similar results’. Best to explain in terms of inter-rater reliability. (Problem is that we use ‘reliable’ in common language and not always appropriate to more technical meaning.) The A2 Examination: January 2010 exam Unit 4 (h) The psychologist noticed that male and female participants seemed to have responded rather differently to treatment. She decided to test the following hypothesis: Female patients with an eating disorder will show greater improvement in their symptoms after treatment with the new therapy than male patients. She used a new set of participants and, this time, used self-report questionnaires instead of interviews with a therapist. Imagine that you are the psychologist and are writing up the report of the study. Write an appropriate methods section which includes reasonable detail of design, participants, materials and procedure. Make sure that there is enough detail to allow another researcher to carry out this study in the future. (10 marks) Limited awareness of conventional reporting style. Students lost sight of what they were doing and e.g. randomly allocated participants to gender groups. No credit for aims or statistical analyses. Again poor expression often obscured meaning. The A2 Examination: June 2010 exam Unit 4 Topic: Research methods 1 8 Outline what is meant by the term peer review in psychological research. (2 marks) 1 9 Explain why peer review is important in psychological research. (5 marks) Didn’t know what peer review was. Not enough elaboration. Didn’t answer ‘why’. Read the text below and answer questions 2 0 , 2 1 and 2 2 . A psychologist was interested in looking at the effects of a restricted diet on psychological functioning. A group of 20 healthy, young adult volunteers agreed to spend four weeks in a research unit. They were kept warm and comfortable but given only water and small amounts of plain food. They were able to socialise with one another and watch television, but they had to keep to strict, set mealtimes and were not allowed to eat anything between meals. The psychologist carried out various tests of emotional and cognitive functioning during this four-week period. One area of interest for the psychologist was the effect of the dietary restriction on the perception of food. He tested this by asking the volunteers to draw pictures of food at the end of each week. When all the drawings had been completed, the psychologist used content analysis to analyse them. 2 0 What is meant by the term content analysis? (1 mark) Didn’t know content analysis. The A2 Examination: June 2010 exam Unit 4 2 1 Explain how the psychologist might have carried out content analysis to analyse these drawings. (3 marks) If 20 answered, then did OK with this. 2 2 The psychologist needed to be sure that his participants understood the nature of the study so that they were able to give informed consent. Write a consent form which would be suitable for this study. Make sure there is sufficient information about the study for the participants to make an informed decision. (5 marks) 2 3 The psychologist was also interested in the effects of a restricted diet on memory functioning and he expected memory to become impaired. The psychologist’s hypothesis was that participants’ scores on a memory test are lower after a restricted diet than before a restricted diet. He gave the volunteers a memory test when they first arrived in the research unit and a similar test at the end of the four-week period. He recorded the memory scores on both tests and analysed them using the Wilcoxon signed ranks test. He set his significance level at 5%. His calculated value was T = 53. State whether the hypothesis for this study is directional or nondirectional. (1 mark) Many focused on procedures rather than ethical issues, or vice versa. Almost all answers correct. Some said ‘yes’ The A2 Examination: June 2010 exam Unit 4 24 Many gained full marks. Using Table 1, state whether or not the psychologist’s result was significant. Explain your answer. (3 marks) Read the text below and answer questions 2 5 to 2 8 . A psychologist is using the observational method to look at verbal aggression in a group of children with behavioural difficulties. Pairs of observers watch a single child in the class for a period of one hour and note the number of verbally aggressive acts within ten-minute time intervals. After seeing the first set of ratings, the psychologist becomes concerned about the quality of interrater reliability. The tally chart for the two observers is shown in Table 2. Some gained 1 mark because they couldn’t explain it. The A2 Examination: June 2010 exam Unit 4 2 5 Use the data in Table 2 to sketch a scattergram. Label Large number didn’t know what the axes and give the scattergram a title. (4 marks) a scattergram was, and drew e.g. frequency polygon. 2 6 Using the data in Table 2, explain why the Some candidates wasted time psychologist is concerned about inter-rater reliability. (4 explaining inter-rater reliability or marks) discussing reliability. 2 7 Identify an appropriate statistical test to check the Relatively few candidates could inter-rater reliability of these two observers. Explain why answer. this is an appropriate test. (3 marks) 2 8 If the psychologist does find low reliability, what Good discriminator because most could she do to improve inter-rater reliability before could offer one solution but proceeding with the observational research? (4 marks) often could not elaborate. The A2 Examination: January 2011 xam Unit 4 Topic: Media Psychology 0 9 In a study, researchers investigated celebrity worship 0 9 Could identify appropriate issues in young people. They sent two questionnaires to but failed to link them to the research. several hundred university students. One questionnaire measured attitudes to celebrity and the other questionnaire measured self-esteem. The researchers analysed the completed questionnaires and found a significant correlation between low self-esteem and high levels of celebrity worship. Explain one methodological and one ethical issue that might have arisen in this study. (2 marks + 2 marks) The A2 Examination: January 2011 exam Unit 4 Topic: Anomalistic Psychology 1 6 To investigate this, a researcher asked participants to Could explain reliability and complete a reliable and well-validated scale measuring validity but not why this is belief in the paranormal. Each participant was then important. scored on their attempt to solve a set of reasoning problems. What is meant by a ‘reliable and well-validated’ scale? Explain why it is important to use such a scale when measuring paranormal beliefs. (2 marks + 2 marks) January 2011 exam Unit 4 Topic: Psychological Research and Scientific Method A teacher has worked in the same primary school for two years. While chatting to the children, she is concerned to find that the majority of them come to school without having eaten a healthy breakfast. In her opinion, children who eat ‘a decent breakfast’ learn to read more quickly and are better behaved than children who do not. She now wants to set up a pre-school breakfast club for the children so that they can all have this beneficial start to the day. The local authority is not willing to spend money on this project purely on the basis of the teacher’s opinion and insists on having scientific evidence for the claimed benefits of eating a healthy breakfast. 1 9 Explain why the teacher’s personal opinion cannot be accepted as scientific evidence. Refer to some of the major features of science in your answer. (6 marks) 1 9 Difficulty trying to apply knowledge. Lots of answers mentioned paradigm shift, gained no marks. January 2011 exam Unit 4 A psychologist at the local university agrees to carry out a study to investigate the claim that eating a healthy breakfast improves reading skills. He has access to 400 five-year-old children from 10 local schools, and decides to use 100 children (50 in the experimental group and 50 in the control group). Since the children are so young, he needs to obtain parental consent for them to take part in his study. 2 0 The psychologist used a random sampling method. Didn’t give answers worth 3 Explain how he could have obtained his sample using this marks. method. (3 marks) 2 1 Explain limitations of using random sampling in this study. (3 marks) Said it wouldn’t represent the whole population whereas the point is unrepresentativeness of the target population. Good answer – some parents might not give consent and therefore not a random sample. January 2011 exam Unit 4 2 2 Explain why it is important to operationalise the independent variable and the dependent variable in this study and suggest how the psychologist might do this. (5 marks) 2 3 The psychologist used a Mann-Whitney test to analyse the data. Give two reasons why he chose this test. (2 marks) 2 4 He could have used a matched pairs design. Explain why this design would have been more difficult to use in this study. (2 marks) 2 5 Other than parental consent, identify one ethical issue raised in this study and explain how the psychologist might address it. (2 marks) Beyond many candidates. How?e.g. fat, sugar Mostly correct answers Weak answers e.g. ‘difficult to match variables’. Identified appropriate issue but overlooked second part. January 2011 exam Unit 4 2 6 The psychologist asks some of his students to conduct a separate observational study at the same time on the same group of children. The aim of this observational study is to test the idea that eating a healthy breakfast affects playground behaviour. Candidates failed to read the whole question. Design an observational study to investigate the effects of a healthy breakfast on playground behaviour. Include in your answer sufficient detail to allow for reasonable replication of the study. You should state the hypothesis you are setting out to test. Failed to write a suitable hypothesis. In your answer, refer to: •an appropriate method of investigation •materials/apparatus and procedure. Lacked sufficient detail for replication. Justify your design decisions. (12 marks) Many wrote about sampling and ethics which were already dealt with. Couldn’t identify the IV. Used totally impractical ideas. Could include training of observers as part of method. The A2 Examination: June 2011 exam Unit 4 Topic: The Psychology of Addictive Behaviour A study into the effects of warnings on cigarette packets has found that these vary depending on the reason why people smoke in the first place. College students were given questionnaires to assess whether self-esteem self-esteem not in spec played a role in their motivation to smoke. They were then shown cigarette packets with either death-related warnings (eg ‘smokers die young’) or death-neutral warnings (eg ‘smoking makes you unattractive’). Students, to whom smoking was important to their self-esteem, were not put off by warnings of death on cigarette packets. Surprisingly, their attitude to smoking became more positive after being shown such messages. However, warnings related to the source of their self-esteem, (eg ‘smoking makes you unattractive’), significantly reduced positive attitudes to smoking in this group. The questionnaires consisted of statements such as ‘Smoking makes me feel valued’ and students had to indicate in a tick box the extent to which they agreed/disagreed with each statement. Provided a question instead of a statement. Many thought if words were involved it must be qualitative. NB self10 Suggest one other possible statement that could have been used to assess the esteem not role of self-esteem. State whether this kind of data is qualitative or quantitative. on spec now (2 marks) 1 1 Explain one strength and one limitation of using a questionnaire in this study. Good (2 marks + 2 marks) The A2 Examination: June 2011 exam Unit 4 Psychological Research and Scientific Method It is thought that colours might affect our performance when carrying out certain tasks. Research in this area has been inconclusive. Some studies have shown that red improves performance but others have found the opposite. It could be that these contradictory results have arisen because red is only beneficial for certain kinds of mental processing. Some psychologists tested this hypothesis in a series of independent-groups design experiments using students at a Canadian University. The experiments involved computer tasks, with either a red, blue or neutral back ground appearing on the monitor. The researchers found that participants were better at a wordrecall task and a spell-checking task when the screen background was red rather than blue or neutral. However, participants thought of more creative ideas when the screen was blue rather than red or neutral The researchers concluded that red is beneficial for tasks that require attention to detail whereas blue aids creativity. 1 7 What were the researchers’ aims in this study? (2 marks) OK Imagine that you are writing up the report for this series of experiments. 1 8 What is the purpose of the introduction section of a report? (2 marks) Don’t know it, writing abstracts The A2 Examination: June 2011 exam Unit 4 A psychological report also contains a discussion section. Researchers are expected to consider their findings critically and discuss issues such as validity. Accurate, true = 0 marks, 1 9 What is meant by validity? (1 mark) lengthy answers 2 0 Explain how one factor in this study might affect its internal validity and how Muddled one factor in this study might affect its external validity. (2 marks + 2 marks) 2 1 In the discussion section, researchers are also expected to consider any Good e.g. possible applications of their research. Suggest one practical application that use of might arise from these findings. (2 marks) colour on classroom walls or in textbooks. In a further experiment, participants were given 20 blue shapes and 20 red Good shapes. They were then asked to pick 5 shapes and use them to make a toy suitable for a child aged between five and eleven years. They were given a limited time to carry out this task. Participants given red shapes made toys that independent judges rated to be more practical but less original, whereas participants given blue shapes made more creative toys. 2 2 Explain why the researchers asked independent judges to rate the toys. (2 marks) The A2 Examination: June 2011 exam Unit 4 2 3 Write a set of standardised instructions that would be suitable to read out to participants in this experiment. (5 marks) Poor, gave consent forms and focused on ethics. Answers too brief. Psychological research suggests an association between birth order and certain abilities. For example, first-born children are often logical in their thinking whereas later-born children tend to be more creative. A psychologist wonders whether this might mean that birth order is associated with different career choices. Surprisingly poor, some She decides to investigate and asks 50 artists and 65 lawyers giving a correlation or null whether they were the first-born child in the family or not. hypothesis. 2 4 Write a non-directional hypothesis for this study. (2 marks) 2 5 Identify an appropriate sampling method for this study and Some said notice in shop explain how the psychologist might have obtained such a window which wouldn’t sample. (3 marks) work for artists and lawyers. Any sampling method got 1 mark. The A2 Examination: June 2011 exam Unit 4 The psychologist found the following results: • 20 out of the 50 artists were first-born children • 35 out of 65 lawyers were first-born children She analysed her data using a statistical text and calculated a value of χ2 = 2.27. She then looked at the relevant table to see whether this value was statistically significant. An extract from the table is provided below. 2 6 Imagine that you are writing the results section of the report on the investigation. Using information from the description of the study above and the relevant information from the statistical table, provide contents suitable for the results section. You must provide all of the following: • An appropriately labelled 2 x 2 contingency table (2) [OK] • A sketch of an appropriately labelled bar chart (3) [miss labels] • Identification of the appropriate statistical test with justification for its use (1 + 2) [some say Spearman’s] • Identification of the appropriate significance level (1) [OK] • A statement of the results of the statistical test in relation to the hypothesis. (3 marks) The A2 Examination: Jan 2012 exam Unit 4 Topic: Media Psychology Used e.g. social desirability or 0 7 Researchers conducted a study of media influences on demand characteristics. anti-social behaviour. The researchers asked child participants to name their favourite TV programmes. Fifteen years later, the researchers assessed the same participants for levels of anti-social behaviour. Two measures of adult anti-social behaviour were obtained for each participant. Measure A: The researchers interviewed a person who knew the participant well and asked them about the participant’s behaviour. Measure B: The researchers studied official records of the participant’s criminal convictions. The researchers concluded that there was a link between watching violent TV programmes as a child and levels of adult aggression. Other than ethical issues, explain two methodological problems involved in the study described above. (4 marks) The A2 Examination: Jan 2012 exam Unit 4 Psychological Research and Scientific Method Two psychologists investigated the relationship between age and recall of medical advice. Previous research had shown that recall of medical advice tended to be poorer in older patients. The study was conducted at a doctor’s surgery and involved a sample of 30 patients aged between 18 and 78 years. They all saw the same doctor, who made notes of the advice that she gave during the consultation. One of the psychologists interviewed each of the patients individually, immediately after they had seen the doctor. The psychologist asked each patient a set of questions about what the doctor had said about their diagnosis and treatment. The patients’ responses were recorded and then typed out. Working independently the psychologists compared each typed account with the doctor’s written notes in order to rate the accuracy of the accounts on a scale of 1–10. A high rating indicated that the patient’s recall was very accurate and a low rating indicated that the patient’s recall was very inaccurate. 1 6 The psychologists decided to propose a directional hypothesis. Why was Some wrote a directional hypothesis appropriate in this case? (1 mark) too much. 1 7 Write a suitable directional hypothesis for this investigation. (3 marks) They can’t do this! 1 8 The psychologists were careful to consider the issue of reliability during Again wrote the study. What is meant by reliability? (1 mark) too much. The A2 Examination: Jan 2012 exam Unit 4 1 9 Explain how the psychologists might have assessed the reliability of their ratings. (3 marks) Good discriminator. Some considered reliability of the study, which produced weak answers. Said ‘test-retest’ but then could explain how. 2 0 This study collected both qualitative and quantitative data. Well answered, using From the description of the study above, identify the examples. qualitative data and the quantitative data. (2 marks) Most achieve full marks. The psychologists used Spearman’s rho to analyse the data from their investigation. They chose to use the 0.05 level of significance. The result gave a correlation coefficient of −0.52. 2 1 Give two reasons why the psychologists used Spearman’s rho to analyse the data. (2 marks) The A2 Examination: Jan 2012 exam Unit 4 2 2 Using Table 1 below, state whether the result is significant or not significant and explain why. (2 marks) Students confused by negative sign. 2 3 Explain what is meant by a Type 1 error. (2 marks) 1/3 confused Type 1 and 2 Many avoided the question! Many relied on a rote learned response that the 5% significance level avoids Type 1 errors. 2 4 Use the information in Table 1 above to explain why the psychologists did not think that they had made a Type 1 error in this case. (3 marks) The A2 Examination: Jan 2012 exam Unit 4 The psychologists then wanted to see whether the use of diagrams in medical consultations would affect recall of medical information. In a laboratory experiment involving a medical consultation role-play, participants were randomly allocated to one of two conditions. In Condition A, a doctor used diagrams to present to each participant a series of facts about high blood pressure. In Condition B, the same doctor presented the same series of facts about high blood pressure to each participant but without the use of diagrams. At the end of the consultation, participants were tested on their recall of facts about high blood pressure. Each participant was given a score out of ten for the number of facts recalled. 2 5 In this case, the psychologists decided to use a laboratory experiment rather than a field experiment. Discuss advantages of carrying out this experiment in a laboratory. (4 marks) 2 6 Identify an appropriate statistical test that the psychologists could use to analyse the data from the follow-up study. Give one reason why this test is appropriate. (2 marks) Very poor. Failed to refer to stem in their answer. Some wrote about disadvantages. Most got full marks. The A2 Examination: Jan 2012 exam Unit 4 2 7 Research has shown that music can affect the ability to concentrate. Design an experiment that could be carried out in a classroom to test the effects of two different kinds of music on a task requiring concentration (eg word search). You must use a repeated measures design. In your answer you should: •fully operationalise the independent and dependent variables •provide details of how you would control extraneous variables •describe the procedure that you would use. You should provide sufficient detail for the study to be carried out. (10 marks) Some students not well prepared and gained few marks. Common errors: •Ignoring the requirement to use repeated measures and converting the experiment to an independent groups design •Failing to counterbalance order of presentation of the two types of music •Producing two concentration tests which were not matched for difficulty •Testing music v no music •Focussing on trivial controls (breakfast, temperature) and ignoring important ones (volume of music). The A2 Examination: June 2012 exam Unit 4 Section C Research methods and scientific method 1 6 Explain what is meant by replicability. Why is replicability an important feature of science? (5 marks) A maths teacher wondered whether there was a relationship between mathematical ability and musical ability. She decided to test this out on the GCSE students in the school. From 210 students, she randomly selected 10 and gave each of them two tests. She used part of a GCSE exam paper to test their mathematical ability. The higher the mark, the better the mathematical ability. She could not find a musical ability test so she devised her own. She asked each student to sing a song of their choice. She then rated their performance on a scale of 1–10, where 1 is completely tuneless and 10 is in perfect tune. 1 7 Suggest a suitable non-directional hypothesis for this study. (3 marks) 1 8 Why might the measure of musical ability used by the teacher lack validity? (3 marks) Could define but not explain, poor answers. Best to use the scientific process as basis. Students continue to find it difficult to write hypotheses. 40% got zero marks because directional and/or not a correlation. Answered well. The A2 Examination: June 2012 exam Unit 4 1 9 Explain how the teacher could have checked the reliability of the mathematical ability test. (3 marks) 2 0 Explain why the teacher chose to use a random sample in this study. (2 marks) The results of the study are given in Table 1. Table 1: Mathematical ability test scores and musical ability ratings for 10 students 2 1 In your answer book, sketch a graph to show the data in Table 1. Give the graph an appropriate title and label the axes. (3 marks) 40% got no marks, reliability confused with validity. Pilot study got no marks. 1 mark by referring to the method as being likely to yield a more representative sample. The weakest students simply defined random sample and went no further. About 1/3 drew the wrong kind of graph e.g. a bar chart. Lost marks by omitting labels. The A2 Examination: June 2012 exam Unit 4 2 2 Discuss what the data in Table 1 and the graph that you have sketched seem to show about the relationship between mathematical ability and musical ability. (3 marks) Better students noted the presence of two outliers which weakened the overall strength of the relationship and some commented on the impact of outliers in a small sample. The A2 Examination: June 2012 exam Unit 4 2 3 The teacher noticed that most of the students who were rated highly on musical ability were lefthanded. The teacher is aware that her previous definition of musical ability lacked validity. Design a study to test whether there is a difference in the musical ability of left-handed students and right-handed students. You have access to a sixth form of 200 students. You should: •identify the design that you would use •explain an appropriate sampling method and justify your choice •describe the procedure that you would use, including details of how you would •assess musical ability •write a suitable debrief for these participants. (10 marks) 2 4 In your answer book, draw a table to show how you would record your results. Identify an appropriate statistical test to analyse the data that you would collect. Justify your choice. (3 marks) Some students had an impressive understanding of experimental design but often: • Suggested repeated measures (inappropriate). • suggesting a sampling method but not explaining how • assuming that a maths test also needed to be completed (ie incorrect IV) • failing to provide any procedural information • producing an unsuitable debrief • providing standardised instructions and claiming they were a debrief. Some produced a summary table. The A2 Examination: Jan 2013 exam Unit 4 Psychological Research and Scientific Method Some studies have suggested that there may be a relationship between intelligence and happiness. To investigate this claim, a psychologist used a standardised test to measure intelligence in a sample of 30 children aged 11 years, who were chosen from a local secondary school. He also asked the children to complete a self-report questionnaire designed to measure happiness. The score from the intelligence test was correlated with the score from the happiness questionnaire. The psychologist used a Spearman’s rho test to analyse the data. He found that the correlation between intelligence and happiness at age 11 was +0.42. 1 7 Write an operationalised non-directional hypothesis for this study. (2 marks) 1 8 Identify an alternative method which could have been used to collect data about happiness in this study. Explain why this method might be better than using a questionnaire. (4 marks) Hypothesis writing is problematic for many students. Less than a third students achieved the full 2 marks available and a further third scored no marks at all, having mistakenly written a directional hypothesis or one which predicted a difference. Many responses were lacking in clarity or failed to operationalise the variables. “There is a correlation (relationship) between pupils’ scores on a standardised intelligence test and their scores on a questionnaire measuring happiness”. Weaker students became sidetracked into describing the possible method in detail (i.e. observational categories) and lost focus on The A2 Examination: Jan 2013 exam Unit 4 1 9 What is meant by internal validity? (1 mark) 2 0 Describe how the internal validity of the happiness questionnaire could be assessed. (3 marks) One mark was achieved by only about half of the students. About 70% of students achieved no marks at all. Many answers confused validity with reliability. Most common methods were assessing concurrent and face validity. Good answers. 2 1 A Spearman’s rho test was used to analyse the data. Give two reasons why this test was used. (2 marks) About a third of students managed to pick up the full 3 marks. Most of the remainder were able to say the result was significant, gaining one mark but went on to select the incorrect critical value from the table. 2 2 The psychologist used a non-directional hypothesis. Using Table 1, state whether or not the correlation between intelligence and happiness at age 11 (+0.42) was significant. Explain your answer. (3 marks) The A2 Examination: Jan 2013 exam Unit 4 2 3 Five years later, the same young people were asked to complete the intelligence test and the happiness questionnaire for a second time. This time the correlation was -0.29. With reference to both correlation scores, outline what these findings seem to show about the link between intelligence and happiness. (4 marks) The report was subjected to peer review before it was published in a journal. 2 4 What is meant by peer review? (2 marks) 2 5 Explain why peer review is an important aspect of the scientific process. (4 marks) Less than 5 % of answers achieved the full 4 marks. Many students were able to identify that the scores demonstrated different kinds of relationships (positive and negative) but were unable to take this further and think about possible explanations. Better answers focused on the inability to establish cause and the role played by other variables, in this case age. Some made use of their knowledge about reliability. Just under half of students achieved the full two marks. Many fail to understand that peer review occurs prior to publication. Less than 5% of students achieving the full 4 marks available. Most students had a basic idea that peer review prevents weak or fraudulent research getting into the public domain but could say little beyond this. The A2 Examination: Jan 2013 exam Unit 4 2 6 A psychology student was asked to design an investigation to see whether taking exercise could increase feelings of happiness. She proposed to do an experiment. She decided to recruit a sample of volunteers who had just joined a gym, by putting up a poster in the gym. She planned to carry out a short interview with each volunteer and to give each one a happiness score. She intended to interview the volunteers again after they had attended the gym for six weeks and to reassess their happiness score to see if it had changed. The psychology student’s teacher identified a number of limitations of the proposed experiment. Explain one or more limitations of the student’s proposal and suggest how the investigation could be improved. (10 marks) Stronger students identified the lack of operationalisation and control at the heart of the proposed study. Quite a lot of the modifications suggested were weak (e.g. ‘do a random sample’). Better answers were structured around identification and discussion of a limitation (e.g. lack of control) followed by a well-developed argument about different ways to improve this. Teachers are encouraged to do some practical work with students and encourage them to plan ‘thought experiments’. It was clear that some students were very familiar with designing experiments and they had a strong advantage here. The A2 Examination: June2013 exam Unit 4 Psychological Research and Scientific Method In an observational study, 100 cars were fitted with video Almost half of the answers cameras to record the driver’s behaviour. Two psychologists achieved no marks at all. used content analysis to analyse the data from the films. They found that 75% of accidents involved a lack of attention by the driver. The most common distractions were using a hands-free phone or talking to a passenger. Other distractions included looking at the scenery, smoking, eating, personal grooming and trying to reach something within the car. 1 8 What is content analysis? (2 marks) 1 9 Explain how the psychologists Most students were able to gain some marks here might have carried out content despite poor performance on question 18. analysis to analyse the film clips of Fw appreciated that behavioural categories need to driver behaviour. (4 marks) come from somewhere, whether that is from pilot work or previous research. 2 0 Explain how the two Many failed to gain the three marks. psychologists might have assessed A few students became side-tracked into improving the reliability of their content reliability and a small number used split half which analysis. (3 marks) was inappropriate. The A2 Examination: June2013 exam Unit 4 The psychologists then designed an experiment to test the effects of using a hands-free phone on drivers’ attention. They recruited a sample of 30 experienced police drivers and asked them to take part in two computer-simulated driving tests. Both tests involved watching a three-minute film of a road. Participants were instructed to click the mouse as quickly as possible, when a potential hazard (such as a car pulling out ahead) was spotted. Each participant completed two computer-simulated driving Many students provided a tests: basic answer referring to the need for less ● Test A, whilst chatting with one of the psychologists on a hands-free phone participants or the removal of individual differences but ● Test B, in silence, with no distractions. The order in which they completed the computer tests was were unable to provide counterbalanced. further explanation of why 2 1 Explain why the psychologists chose to use a repeated this would be important in measures design in this experiment. this experiment. (3 marks) 2 2 Identify one possible extraneous variable About 75% of students achieved no marks at in this experiment. Explain how this variable all. few students showed any awareness of the may have influenced the results of this need to match the two hazard perception experiment. (3 marks) tests. The A2 Examination: June2013 exam Unit 4 2 3 Explain how one factor in this experiment might affect its external validity. (3 marks) 2 4 Explain one or more ethical issues that the psychologists should have considered in this experiment. (4 marks) 2 5 Write a set of standardised instructions that would be suitable to read out to participants, before they carry out Test A, chatting on a handsfree phone. (5 marks) This question was answered well, with most students able to refer to population or ecological validity. Many answers to this question displayed a marked lack of common sense. many students claimed that watching a 3minute film of a road would be traumatic, leading police drivers to suffer psychological harm. Others referred to possible deception and failed to appreciate that the purpose of the experiment is rather obvious in a repeated measures design. Good answers. Some failed to gain full credit as their instructions referenced both conditions or failed to include a check of understanding. The A2 Examination: June2013 exam Unit 4 The computer simulator measured two aspects of driver behaviour: ● the number of hazards detected by each driver ● the time taken to respond to each hazard, in seconds. The mean scores for each of these measures is shown in Table 1. Table 1 Table to show the mean number of hazards detected and mean reaction times in seconds for Test A and Test B About one third of students gained the full marks or identifying the Wilcoxon test with appropriate justification but just under half gained one mark only for The psychologists then used an inferential statistical test to identification of the test. assess whether there was a difference in the two conditions. Common problems 2 6 Identify an appropriate statistical test to analyse the included justification as a difference in the number of hazards detected in the two test of difference which conditions of this experiment. Explain why this test of gained no credit as it was difference would be appropriate. (3 marks) included in the question. The A2 Examination: June2013 exam Unit 4 They found no significant difference in the number of hazards detected (p > 0.05), but there was a significant difference in reaction times (p ≤ 0.01). 2 7 Explain why the psychologists did not think that they had made a Type 1 error in relation to the difference in reaction times. (2 marks) 2 8 Replication is one feature of the scientific method. The psychologists decided to replicate this experiment using a larger sample of 250 inexperienced drivers. Explain why replication of this study would be useful. (3 marks) Some became confused between type 1 and type 2 errors and others referred to the number of hazards detected rather than reaction times. This question was answered reasonably well, with many students referring to the greater potential for generalisation in a larger sample of inexperienced drivers. Some also referred to the general importance of replication to check findings in the context of the experiment, which was creditworthy.