UNIT PSY 2 – PSYCHOLOGY: CORE STUDIES & APPLIED RESEARCH METHODS PREPARATION & REVISION The aim of this handbook is to help you prepare and revise for the unit named PSY2 in your A Level course in Psychology. It is not intended to take the place of your class work nor of the full textbook covering the course, but it should help you revise and prepare for the examination. CONTENTS PSY 2 – THE TEN CORE STUDIES - An Overview 02 THE TEN CORE STUDIES 1 OPINIONS & SOCIAL PRESSURE Solomon ASCH (1956) 2 BEHAVIOURAL STUDY OF OBEDIENCE Stanley MILGRAM (1963) 3 PREDICTION OF HEALTH CHANGES FROM PRECEEDING LIFE CHANGES Richard RAHE (1970) 4 LANGUAGE & MEMORY Elizabeth LOFTUS and PALMER (1974) 5 HUMAN MATE PREFERENCES David BUSS (1989) 6 FORTY FOUR JUVENILE THIEVES John BOWLBY (1944) 7 THE VISUAL CLIFF Eleanor Gibson and Richard Walk (1960) 8 SIGN LANGUAGE TO CHIMPANZEE Gardner and Gardner (1969) 9 BEING SANE IN INSANE PLACES David ROSENHAN (1973) 10 HEMISPHERE DECONNECTION Roger SPERRY (1968) 03 - 04 PSY 2 – APPLIED RESEARCH METHODS INTRODUCTION & PRACTICE 23 - 31 05 - 06 07 - 08 09 - 10 11 - 12 13 - 14 15 - 16 17 - 18 19 - 20 21 - 22 1 PSY 2 - The Ten Core Studies - An Overview The ten Core Studies cover research drawn from the main areas of Psychology. These studies give you the chance to study a wide range of studies so that you can become familiar with the diversity of psychological enquiry into human behaviour, emotion, and cognition. In the examination you will be expected to demonstrate your knowledge and understanding of the aims, procedures and findings of the research involved in the core studies. In addition, you will also be expected to assess each of the core studies critically. This means evaluating each study, and identifying its strengths and weaknesses. For each Core Study, you should be able to describe: Procedures Findings/conclusions You should also be able evaluate the core studies in these areas (where appropriate): Ethical implications of the research Validity (experimental and/or ecological) Reliability Sampling biases (gender and/or cultural) THE CORE STUDY SOCIAL 1 – ASCH (1956) SOCIAL 2 – MILGRAM (1963) Opinions & Social Pressure Behavioural study of obedience PHYSIOLOGICAL 1 – RAHE et al. (1970) PHYSIOLOGICAL 2 – SPERRY (1968) Prediction of health changes from preceding life changes Hemisphere deconnection and unity in conscious awareness COGNITIVE 1 – GARDNER & GARDNER (1969) COGNITIVE 2 – LOFTUS & PALMER (1974) Teaching sign language to a chimpanzee DEVELOPMENTAL 1 – BOWLBY (1944) DEVELOPMENTAL 2 – GIBSON & WALK (1960) Forty-four juvenile thieves: their characters and home lives The visual cliff INDIVIDUAL DIFFERENCES 1 – BUSS (1989) INDIVIDUAL DIFFERENCES 2 – ROSENHAN (1973) Sex differences in human mate preferences On being sane in insane places Reconstruction of automobile destruction: language & memory 2 1 CONFORMITY - Opinions and Social Pressure Solomon ASCH (1956) INTRODUCTION Everyone is open to pressure from the people around them, especially when the people applying the pressure are in the majority. In other words, we are all under social pressure to conform to the views and opinions of the majority. Conformity can be defined as the tendency to alter our beliefs, opinions, attitudes and behaviour to fit in with the majority view. In fact, it is suggested that even our perceptions, the way we see things, can be affected by group pressure. AIMS Solomon Asch (1956) investigated how far the perception of individuals in the minority could be affected by pressure from groups in the majority even when those in the minority could clearly perceive that those in the majority were wrong in their responses. PROCEDURE In total 123 American male undergraduates were tested in groups of six to nine participants seated either in a straight line or around a table. All the participants, except one (the naïve participant), were stooges/confederates of the researcher. Asch showed the participants a series of lines – a standard line and three similar lines. The task was to call out, one at a time, which of the three lines (A, B or C) matched the standard line (X) in length. There were 18 trials. The confederates were instructed to give the same incorrect answer on 12 critical trials. Answers were called out loud, and the naïve participant was always last or second last to call out his answer. In control trials, fewer than 1% of participants made errors when there was no pressure to conform. FINDINGS On the 12 critical trials, nearly 37% of the responses made by the naïve participants were incorrect. This means these responses conformed to the incorrect responses given unanimously by the confederates. 25% of the participants never gave a wrong answer; thus 75% conformed at least once. 3 Just to confirm that the stimulus lines were clear and unambiguous, Asch conducted control trials with no confederates giving the wrong answers. Asch found that people made mistakes about 1% of the time. CONCLUSIONS Asch’s experiment shows that there is a surprisingly strong tendency for people to conform to group pressures even when the answer is clear and unambiguous. In fact, the findings surprised Asch who had anticipated there would only be low levels of conformity, if any at all. Asch also noted the fact that on two-thirds of the trials his participants resisted the pressure to conform, remained independent, and gave answers that corresponded to the evidence before their eyes. Asch then went on to investigate the factors that influence people to conform and those factors that influence people to resist conforming to social pressure. CRITICISMS Asch’s experiment has been criticized because the task, estimating the length of lines, was rather trivial and insignificant. Some participants would be willing to conform to save face. On a more important task we would expect conformity levels to drop. The fact that participants had to answer out loud, and in a group of strangers, meant there were special pressures on them to conform, such as not wanting to sound stupid and wanting to be accepted by the group. The findings, therefore, only tell us about conformity in special circumstances. The participants in the study were not a representative sample. They were all American male undergraduates, and it has been claimed they belonged to a particularly conformist society, America in the 1950s. When Asch’s experiment was repeated in England in the 1970s, only one student conformed on nearly 400 trials. There are also ethical issues about the experiment. The naïve participants did not enjoy informed consent. In fact, they were deceived about the purpose of the experiment, and they were not informed they could withdraw at any time. Asch himself reported that some of the participants were distressed and uncomfortable during the experiment. On the positive side, Asch demonstrated the influence of conformity in a clear and unambiguous way. The task was unambiguous. He tested the participants’ ability to choose the correct answer before the main study. The answers were clearly correct or wrong. Therefore, conformity could be measured in an objective way. 4 2 BEHAVIOURAL STUDY OF OBEDIENCE Stanley Milgram’s Shocking Obedience Study (1963) INTRODUCTION Following the Second World War, many people believed that the Germans had carried out their atrocities in the concentration camps because ‘the Germans are a highly obedient nation who follow orders whether or not these orders are moral or immoral.’ Stanley Milgram wanted to disprove the ‘Germans are different’ hypothesis. Milgram wanted to investigate the conditions under which people would obey instructions from authority even when those instructions went against their moral beliefs. AIM Stanley Milgram (1963) investigated how obedient people would be when asked to commit immoral acts by people perceived to be in authority. PROCEDURES Male participants for the experiment were recruited by an advertisement offering $4.50 to take part in a study of memory and learning. This was a deception as the experiment actually investigated how far they were willing to obey orders given by authority. The experiment took place at the Yale University psychology department. When they arrived, they were met by the experimenter wearing a grey lab coat. They were introduced to a Mr Wallace, who was a confederate pretending to be another participant – the learner. The experimenter told the naïve participant that the experiment was about the effects of punishment on learning. The experimenter explained the punishment was to take the form of electric shocks delivered via a shock generator by the teacher, the naïve participant. The teacher then saw the learner being strapped into a chair with his arms attached to electrodes. Sitting in an adjoining room, the teacher/participant was instructed to deliver a shock to Mr Wallace each time he made a mistake or did not answer on a task involving pairs of words, e.g. girl-blue. The teacher gave the electric shocks using the generator which had a number of switches. Each switch was clearly marked with a voltage level (starting at 15 volts) and a description (‘slight shock’). The shocks went up 15 volts at a time and reached a maximum of 450 volts. The learner gave mainly wrong answers and received his (fake) shocks in silence until they reached 300 volts (very strong shock). The teachers were given 4 verbal prods to encourage them to keep on shocking the learner to the maximum 450 volts. For example, “You have no other choice, you must go on.” 5 FINDINGS Of the participants, 65% continued giving shocks to the maximum of 450 volts. Before the experiment, a group of staff at the university had predicted only 0.1% would give the maximum shock. Many of the participants showed signs of distress (such as twitching, giggling nervously, digging their nails into their flesh, and verbally attacking the experimenter). Three of the participants suffered uncontrollable seizures. CONCLUSIONS Milgram concluded the ‘Germans are different’ hypothesis was false. Milgram’s participants were 40 ‘ordinary’ Americans living in a fairly small typical town. Their high level of obedience shows that we all tend to obey authority figures in particular situations. If we had lived in Nazi Germany during the 1930s, we might have acted just as obediently. Milgram concluded that people are likely to obey orders if they feel they are following orders from people who have power and authority over them. In addition, the less accountable and personally responsible they feel, the more likely people are to obey orders. In other words, “I did it because I was ordered to and therefore I had no choice.” CRITICISMS The experimental and ecological validity of the experiment have been questioned. Critics argue that Milgram’s experimental situation was absurd – participants were asked to shock someone to death if necessary, because they could not remember that ‘blue’ was paired with ‘girl’. The situation was unreal, the task unbelievable, and therefore the conclusions had low experimental and ecological validity. Critics such as Orme and Holland (1968) claim participants did not believe what was happening in the experiment, so they relinquished (gave up) personal responsibility for their actions and relied on ‘experts’ who ‘must know what they’re doing’. Indeed, one of the verbal prods was “I’m responsible for what goes on here.” In effect, Milgram was testing participants’ trust in, and not obedience to, authority. Milgram’s research has regarded as unethical. The participants were not only deceived about the nature of the experiment, but they were also exposed to the risk of emotional and psychological harm. Many of the participants were clearly distressed during the experiment; in fact, three had seizures and many were ‘prodded’ to continue to the maximum by the researcher. To be fair, the participants were debriefed after the experiment, and several months later 74% said they had learned something of personal importance from the experiment. In addition, Milgram’s research did provide crucial information about a crucial aspect of human behaviour, by showing how easy it is to give in to powerful authority. 6 3 PREDICTION OF HEALTH CHANGES FROM PRECEEDING LIFE CHANGES - Richard RAHE (1972) INTRODUCTION Thomas Holmes & Richard Rahe (1967) demonstrated that there is a relationship between changes in our lives and the state of our health. They demonstrated that life changes, desirable or undesirable, can trigger illness. Using their Social Readjustment Rating Scale to measure Life Change Units, Holmes & Rahe (1967) suggested that a score of 150 or more increased the chance of illness by 30%, while a score of 300 or more increased the odds of illness by 50%. However, Holmes & Rahe (1967) based their conclusions on research using participants already suffering from stress-related illnesses. These people looked back over a two-year period and recorded any life changes that had happened. In 1970, Richard Rahe investigated whether Life Change Units could be related to the development of illness in generally healthy participants. AIM Richard Rahe (1970) investigated if there is a prospective correlation between life changes and subsequent/future illness. PROCEDURES Rahe’s (1970) sample consisted of 2664 sailors on three cruisers in the American navy. The participants came from a wide range of backgrounds in terms of education, naval rank, and experience at sea. The study had two major advantages: (a) all the participants were exposed to the same conditions at sea, and (b) the researchers had access to the detailed medical records of the participants, including any medical problem while they were at sea. In addition, a double blind was used. Neither the participants nor the medical staff on board ship knew the research was taking place; therefore they could not be influenced by such knowledge. At the beginning of each naval mission, the participants completed a Schedule of Recent Experience (SRE). This was a version of the Social Readjustment Rating Scale, which recorded any changes in their lives during the previous two years. The SRE was used to calculate a Life Change score for each participant. As each ship returned from its mission, a research doctor came on board and reviewed all the health records. It was then possible to calculate if there was a significant correlation between Life Changes and the health of each participant. 7 FINDINGS/CONCLUSIONS Rahe (1970) found that there was a positive relationship between the Life Changes recorded over a two-year period and the health of the participants. In other words, sailors with high Life Change Unit scores had, in general, suffered from more illnesses during the mission than those with low LCU scores. Rahe (1970) also found that married men were more likely to develop illnesses than young, single sailors. The results of the study support the idea that there is a correlation between LCU scores and illness rates. This is important because we can use LCU scores to predict the development of illness in healthy people, and offer them support and advice. It is important to note that the men on board ship generally suffered from minor illnesses only, and that they had report mainly minor life changes. However, this does not detract from the important conclusion that too many changes in our lives during a short period can lead to the development of illness. EVALUATION – Strengths and Weaknesses Strength - The results from this research support other research that suggests that Life Change scores do have a low, but significant correlation, with stress and health breakdown. This has proved very useful in helping people understand the nature of their illnesses, and what can be done to improve their health. Variations of the Social Readjustment Rating Scale are now widely used. Strength – The research was carried out in well-controlled conditions. Neither the sailors nor the medical staff on board ship knew the nature of this study (double-blind), and this increases the experimental validity of the research. In other words, neither sailors nor staff were influenced by demand characteristics. Weakness - The sample used in this study consisted entirely of American sailors. Therefore, we might question its ecological validity. Would the findings and conclusions hold true for women and for people from different, e.g. non-Western cultures? Weakness - Different people react differently to the same stressful situations; some people might hate them while others actively enjoy them. For example, a wife might happily welcome getting divorced while it may have a very negative impact on the husband. However, in this research there was no allowance for individual reactions to stress. In other words, every participant was allocated the same LCU score whether they found the event/change desirable or undesirable. It might have been better to assess them only on changes they perceived as negative. 8 4 RECONSTRUCTION OF AUTOMOBILE DESTRUCTION LANGUAGE AND MEMORY - Loftus & Palmer (1974) INTRODUCTION You are walking home and you see a child being knocked down by a car in the street. It is not clear to you if the victim is a boy or a girl. A few minutes later a friend says, “Did you see that little girl being knocked down?” You may question whether or it was a girl or a boy. However, that evening, describing the accident to you family, you may well say, “I saw a little girl being knocked down in the High Street this afternoon.” What you have done is build into the original memory the later suggestion that the victim was a little girl. Research has shown that information can be added to a particular memory after the event itself (post-event information), and later recalled as part of the event itself. In other words, the original event is reconstructed to include/incorporate the later information AIM Loftus & Palmer (1974) investigated how information supplied after an event can influence the witness’s memory/recall of that event. PROCEDURES/FINDINGS Student participants were shown a film of two cars involved in an accident. The participants were then asked questions about the speed the cars were going when the accident happened. However, the questions were varied by the inclusion of verbs such as ‘collided’, ‘hit’, ‘smashed’, and ‘bumped into’. For example, “How fast were the cars going when they smashed into each other?” and “How fast were the cars going when they bumped into each other?” The researchers found that participants varied their estimates of speed depending upon the particular verb used in their question. For example, the verb ‘smashed’ elicited the highest estimates of speed. It seems the verb in the question influenced the estimate of the speed. One week later, the participants were asked if they had seen any broken glass after the accident. There was actually no broken glass involved. However, 32% of the ‘smashed’ participants claimed to have seen broken glass while only 14% of the ‘hit’ participants remembered seeing broken glass. In addition, 12% of the control group, who’d been asked no questions at all, remembered having seen broken glass! This study consisted of two laboratory experiments. In both conditions, the IV was the verb used. In the first condition, the DV was the estimate of the speed of the cars; in the second condition, the DV was whether or not the participant had seen broken glass. 9 CONCLUSIONS The researchers concluded that the memories of the car accident could have been influenced by the verb used to describe the intensity of the crash. In other words, this post-event information influenced participants’ recall of what they had seen in the film. They also suggested that participants might have integrated the original memory of the accident with the idea of the cars smashing, hitting, colliding, or bumping. They then reconstructed a memory in which broken glass might have appeared because that is something to be expected in car crashes. The researchers admitted that some of the participants could have given estimates of the speed they thought the researcher wanted. For example, using the verb ‘smashed’ suggests a higher speed regardless of what they had witnessed on the screen, so that’s what some participants gave. STRENGTHS AND WEAKNESSES This investigation consisted of well-controlled experiments. The researchers were able to manipulate the IV, the verb used, and observe its effect on the DVs (the estimate of speed and the recall, or not, of broken glass). All of the variables were well-controlled. For example, Loftus & Palmer (1974) were able to control the ages of the participants, the use of the filmed crash, and where the experiments took place. In addition, all of the participants were asked the same, standardized questions – apart from the changes in the critical verbs. The ecological validity of the investigation is questionable. The experiments were not typical of real-life situations. They were artificial in the sense that they were different from how people normally witness events. For example, when we witness events in everyday life, we often feel personally involved with the people or the action. This was not true in this investigation. Therefore, it may be difficult to generalise the conclusions of the investigation to eye-witnesses in general. In addition, the filmed car accident had very little emotional impact on the participants. Research has shown that events with strong emotional impact often remain detailed and accurate for a long time afterwards. A further problem with the study is the sample of participants. For example, students are used to remembering lots of information, and are usually good at memory tasks compared with other people. Students are not representative of the wider population, so the results are difficult to generalise. It would be useful to replicate the investigation using a crosssection of people in the sample. 10 5 SEX DIFFERENCES IN HUMAN MATE PREFERENCES David BUSS (1989) AIM David Buss (1989) investigated the characteristics that appealed to human males and females in their selection of a mate – husband, wife, partner. He investigated these characteristics across a large number of cultures because he wished to find out what was typical for the human species across these cultures. PROCEDURES Buss and his team surveyed 10,047 men and women in 37 samples from 33 countries. The participants were located on 6 continents and 5 islands. The age of the participants in the sample groups ranged from 17 years in New Zealand to 29 years in West Germany. Sampling techniques varied across the different countries. For example, in New Zealand the sample consisted of high school students from three schools. In West Germany the sample was selected through newspaper advertisements. Occasionally, questionnaires needed to be amended to reflect the cultural differences of the various cultures. For example, in Nigeria polygyny is practised, so questions had to be added to reflect the possibility of multiple wives. The questionnaire included a four-point rating scale where participants had to rate 18 characteristics. These included good financial prospects, good looks, chastity and ambition. The research data was collected by native residents of each country and mailed to the researchers in the USA for analysis. Research assistants were unaware of the main hypotheses of the investigation. FINDINGS Buss found some things were universally desired by men and women everywhere, in all cultures. For example, intelligence, kindness, dependability, emotional stability, good health, and mutual attraction were desired by both men and women in every culture. However, Buss also found there were clear differences between what women desired and men desired. Women valued economic resources and financial stability more than men. They also valued men who had the qualities, such as ambition and industriousness, necessary to secure these resources as and when they were needed. In short, women preferred men who could provide, protect and support. In contrast, men valued only two things more than women did. One was physical attractiveness (smooth skin, shiny hair, an attractive figure), the second was youth. Men wanted women who were younger than they were; how much younger depended upon the 11 age of the man. As men got older, they desired partners who were increasingly younger than themselves. Buss found there were some variations between cultures, and that the most importance of these was the importance of chastity, i.e. being a virgin before marriage. Some cultures such as China feel that virginity before marriage is absolutely essential; chastity is of middling importance in countries like Ireland and Japan; and in Scandinavia chastity is of little importance. CONCLUSIONS Buss concluded everyone, regardless of culture, wants a mate who is intelligent, kind, healthy and dependable. Everyone also wants a relationship that offers love or mutual attraction. And everyone seeks a mate who can help produce and care for their off-spring. Buss also concluded that men and women do have different priorities. Men place great emphasis on physical attractiveness and men often desire women who are younger than themselves. This may be linked to the male need to secure the best females to bear and nurture their off-spring as a way of carrying on their genes. For women, on the other hand, the priority in choosing a mate is his status, his ability to provide for the family, and his ability to secure resources when they are needed. Women also desire men who are older then themselves; this may be because being older and more mature is linked with having greater resources. Buss (1989) concluded that these sex differences “… appear to be rooted in the evolutionary history of our species.” In other words, Buss is offering an evolutionary, sociobiological theory of what humans want in a mate. EVALUATION Buss’s (1989) research does provide some support for an evolutionary, sociobiological explanation of human mate preferences. It is true that men’s chances of reproductive success should be increased if they mate with younger, healthy, adult females. In their turn, women may prefer men who can act as a provider to take care of them during pregnancy, nursing, and the raising of children. It is not surprising if women select men who can provide, protect and support them and their children. The evolutionary explanation is determinist. It suggests that human mating behaviour is determined by genetic drives the individual is hardly aware of. Yet we know that mate selection often depends on individual choices, or on cultural pressures such as arranged marriages. We also know that romantic love plays a huge role in mate selection, particularly amongst Western women, and that this desire for romantic love often overrides considerations such as financial resources and support. 12 6 THE FORTY-FOUR JUVENILE THIEVES STUDY John BOWLBY (1944) INTRODUCTION John Bowlby believed that very young children need to form a strong emotional bond with their mother, or a mother figure, in order to grow up as happy, healthy, wellbalanced adults. He suggested that children separated from or deprived of mother love and attention in early childhood might suffer social, emotional and cognitive damage – the so-called Maternal Deprivation Hypothesis. According to Bowlby, possible long-term effects of maternal deprivation included juvenile delinquency and affectionless psychopathy. AIM In his Forty-Four Juvenile Thieves Study (1944), John Bowlby investigated if there was a link between early maternal separation and the development of juvenile delinquency and affectionless psychopathy. PROCEDURE In this research Bowlby used the case study method. Bowlby looked at case studies of 44 ‘juvenile thieves’ (teenagers convicted of theft) and 44 emotionally-disturbed teenagers to see how many in each group had experienced early maternal separation – in particular, a period of 6 months or more of separation in the first 5 years of their lives. Bowlby used detailed interviews with the participants. He also analysed their personal records, including past school and medical records. Bowlby was also interested in diagnosing a condition he called ‘affectionless psychopathy’ where the individual is incapable of giving or accepting affection. FINDINGS Bowlby found that 40% of the juvenile thieves had been separated from their mothers for at least 6 months during the first 5 years of their lives. In the emotionally-disturbed group, only 5% had experienced similar separation in their early years. He also classified a significant number of the juvenile thieves as affectionless psychopaths. And out of the 14 classes as affectionless psychopaths, 12 had experienced maternal separation. None of the emotionally-disturbed group was classified as a psychopath. 13 CONCLUSION Bowlby concluded that there was a link between maternal separation and the development of juvenile delinquency and affectionless psychopathy. It is important to note that he did not claim that maternal separation ‘caused’ these conditions, but that children who suffered from maternal separation were at risk of developing these conditions. STRENGTHS AND WEAKNESSES Bowlby’s research is important because it reminds us that maternal separation can have damaging effects of a child’s emotional, social and cognitive development. However, several criticisms have been made concerning Bowlby’s procedures and conclusions in this study. The study was retrospective. The participants, including disturbed teenagers, were asked to recall and describe any periods of separation from their early childhood. This was asking them to recall events at least 10 years before the study. These juveniles had to reconstruct their memories, and they might have been able to recover memories of painful events in childhood. In addition, there was no guarantee that the participants’ written records were complete and unbiased. There were no experimental controls in this study. Bowlby knew which group was which. He expected to find ‘affectionless psychopathy’ amongst the juvenile thieves, and this expectation might have influenced his findings. In addition, there was no random sampling of the participants, and no random distribution between the groups. He could have compared a group who had experienced separation from their mothers with a matched group who had experienced no separation. If there was a difference in the outcomes between the two groups, he could have concluded the difference was due to maternal separation. Bowlby ignored the fact that 60% of the juvenile thieves had not experienced maternal separation but had gone on to develop juvenile delinquency. From these finding he could have argued that the lack of maternal separation leads to delinquency! Finally, Bowlby used the term ‘maternal separation’ to describe three different conditions: failure to form any attachment, temporary separation from an attached figure, and the permanent loss of an attached figure. Each of these conditions might have had different effects. 14 7 THE VISUAL CLIFF – Depth Perception in Infants Gibson & Walk (1960) INTRODUCTION Suzie is 7 months old. Out on a family picnic, she crawls away and reaches a fairly steep drop. She peers over the top, then edges cautiously back from the drop. Is her reaction to the danger innate (inborn) or has she learned to avoid such dangers? Developmental psychologists have been fascinated by the ways in which infants perceive the world. In classic research, they have found that infants generally respond to cues for depth by the time they are able to crawl about, that is, by about 6 to 8 months of age. It thus appears that we can say that most infants will avoid “going off the deep end.” They won’t crawl off ledges and tabletops into open space. AIMS Eleanor Gibson and Richard Walk (1960) investigated the development of visual depth perception in infants. They investigated whether depth perception is innate, learned or a combination of both. They also investigated the depth perception in infant goats, chicks, kittens and rats. PROCEDURE The researchers created a ‘visual cliff’. This was actually a glass-topped table that could safely support the weight of the infant participants. A check-patterned tablecloth was positioned just beneath the glass on one half of the table (the ‘shallow side’) and 4-feet below the glass on the other side (the ‘deep side’). This gave the visual impression of a steep drop, a visual cliff, at one en of the table. The researchers tested 36 infants ranging from 6 months to 14 months on a ‘visual cliff’. Each child was placed on the centre board, and its mother called to her infant from the cliff side, then from the shallow side successively. In other words, the infants were encouraged to crawl over the edge of the visual cliff in order to reach their mothers. FINDINGS Of the 36 infants, only 3 of the infants crept onto the plexiglas above the drop. Many of the infants crawled away from the mother when she called to them from the cliff side. Others cried when she stood there because they could not come to her without crossing the apparent drop. Often the infants would peer down through the glass on the deep side and then back away. Some infants patted the glass with their hands as if testing the surface but even then they would refuse to cross the plexiglass and the ‘drop’ below it. 15 CONCLUSIONS Gibson and Walk (1960) concluded that most human infants can discriminate depth by the time they are able to crawl around. It seems our ability to perceive depth matures more quickly than our ability to get around by crawling or walking. They also concluded that human beings depend upon vision to make their way around the world from a very early age. Gibson and Walk (1960) accepted their experiment does not prove that the development of depth perception is innate. They accepted that learning, perhaps by trial and error, also helps the development of depth perception. They suggested that the development of depth perception could be an evolutionary mechanism designed to help infants avoid danger and so have a better chance of survival. Developing the ability to see in depth is vital when you creatures, human and non-human, start moving around independently. EVALUATION The researchers supported their conclusions by further experiments involving young animals, including goats, chicks, kittens and rats. They found that kittens whose eyes had just opened would not venture onto the apparent drop. On the other hand, young rats would run across the drop but would refuse when their whiskers were removed; this demonstrated that touch is a more important sense than vision for rats. It seems then that the survival of a species requires that its members develop discrimination of depth by the time they begin moving around independently, whether at one day (the chick and the goat), three to four weeks (the rat and the cat) or six to 10 months (the human infant). 16 8 TEACHING SIGN LANGUAGE TO A CHIMPANZEE Gardner and Gardner (1969) INTRODUCTION If you want to start a fierce argument, simply ask the question: “Do you think that animals can think?” If they can think, they need some kind of language – a language similar in some ways to human language. Of course, no animal has a human voice box, so if they are to communicate with humans it will probably be through visual communication, such as symbols or sign language. If there is such an animal, it’s probably a primate, and if it’s a primate, it’s likely to be a chimpanzee. Chimpanzees are our closest relatives; we share more than 98% of our DNA with them. So, the question is: can a chimpanzee learn to communicate with human beings through symbols or sign language? AIM Allen and Beatrice Gardner were pioneers in trying to teach primate apes to communicate in a non-spoken language. Gardner and Gardner (1969) attempted to demonstrate that a chimpanzee does have the ability to learn to communicate with a human being in sign language. PROCEDURE: The study, which lasted four years, involved teaching American Sign Language to a female chimpanzee named Washoe who was removed from other chimpanzees when she was 11 months old. The Gardners chose a chimpanzee because chimps are intelligent, sociable and often form strong attachments to human beings. The Gardners decided to teach American Sign Language to Washoe because chimps can move hands, fingers and thumbs flexibly, and because ASL would be equivalent to spoken language. They also thought ASL would be useful because this would allow them to compare Washoe’s progress with that of deaf children who were also learning ASL. The Gardners made sure that Washoe had lots of companions who were also learning ASL. The Gardners used the case study method during her four years of training. Washoe was taught ASL mainly using imitation and operant conditioning, i.e. she was rewarded by being praised and tickled when she produced the correct signs in ASL. Records were kept about the amount of signing behaviour and the number of signs used. A sign was recorded if it was reported by three different observers that Washoe had used it spontaneously and in the correct context. 17 RESULTS/FINDINGS After four years, Washoe was able to use about 130 signs, and she could combine them into short messages, such as ‘Give me sweet’ and ‘Washoe sorry’. Later, she could produce three-word sentences. She was also able to invent some novel phrases, such as ‘water bird’ to mean ‘swan’. Washoe also demonstrated displacement ability, which means referring to something that is not present at the time. For example, she could refer to a bottle when there was no bottle in the room. By the age of five, Washoe’s linguist ability was reported comparable to that of a three-year-old human child. The Gardners hoped that Washoe would pass on what she had learned to her own offspring. Unfortunately, her two babies died soon after birth. However, she adopted an 11 months old chimp named Loulis, and used sign language with him. Loulis learned to imitate and use a number of these signs. EVALUATION The Gardners’ research has been criticised by psychologists who claimed Washoe had been merely trained like a circus animal to use sign language. In other words, she didn’t really understand what she was doing; she had simply been conditioned through imitation and operant conditioning. They suggest there were probably many experiment effects such as the Gardners’ own facial movements and expressions. This unconscious cueing may have influenced Washoe’s performance without them being aware of it. Linguists also pointed out that human children do not acquire language in this artificial way. They claimed human beings were ‘wired for sound’ in a way that non-human animals are not. Critics also claimed Washoe rarely satisfied the criterion we call arbitrariness. Arbitrariness means there is no obvious connection between the form or sound of a word and its meaning. For example, there is no obvious connection between the word ‘boy’ and what the word refers to – a boy. Ethical questions have also been raised about research using primate apes such as Washoe, Loulis, and those who have followed in their footsteps. 1. Do we have the right to remove wild animals from their natural habitats for our research purposes? Should Washoe have been returned to the wild when she was old enough to cope? 2. Can we justify using animals so close to us in DNA in psychology research? 3. Was the study important enough to justify the use of an infant chimpanzee? 4. Should Washoe have been removed from all contact with other infant chimps? 5. Should Washoe have been taught something, human sign language, which is something she would never use in her natural life and situation? 18 9 BEING SANE IN INSANE PLACES David Rosenhan (1973) INTRODUCTION Would you know the difference between a sane and an insane person if he/she were sitting beside you right now? Perhaps you wouldn’t. But you would expect an expert, say, a psychiatrist to notice the difference, especially if he was actually treating that person. Simple, yes? ‘Fraid not. In 1973 sociologist David Rosenhan designed a clever study to test the hypothesis that psychiatrists cannot reliably tell the difference between people who are sane and people who are insane. He was particularly interested in how staff in mental institutions interpreted the behaviour of their patients. He decided the best way to get this information was from inside mental institutions through participant observation. AIMS The aim of this study was to test the hypothesis that psychiatrists cannot reliably tell the difference between people who are sane and those who are insane. Rosenhan was also interested in how the staff, doctors and nurses, interpreted the behaviour of their patients in mental institutions. PROCEDURE/METHOD The study consisted of two parts. In the first part of the study Rosenhan and seven confederates had themselves committed to different mental hospitals by complaining they were hearing voices (a common symptom of schizophrenia). There were three women and five men. The staff did not know these ‘pseudopatients’ were actually part of Rosenhan’s field experiment. The staff assumed the pseudopatients were like any other patients and had no reason to believe the reported symptoms were fake. This allowed the pp’s to observe and take part in the routine of the mental hospitals (participant observation). The pp’s gave a false name and job, but all the other information they gave was true, including their life and medical histories. After they were admitted to the psychiatric ward, the pp’s stopped simulating any symptoms of abnormality. They took part in the ward activities, speaking to staff and patients, as they might ordinarily. When asked how they were feeling by staff, they said they were fine and were no longer experiencing any unusual symptoms. In order to be released from hospital, the pp’s had to convince the staff that they were sane. The pp’s spent time writing notes about their observations. At first this was done secretly, but when they realised the staff ignored this note-taking, they did it quite openly. 19 In the second part of the study, a mental institution was falsely informed that pseudopatients were going to be ‘planted’ amongst their patients. They were asked to try and spot these pp’s; in other words, to spot the patients who were sane. In fact, no pp’s were planted in any of these hospitals. However, many of the regular patients in these hospitals were assessed by the staff as being completely sane. FINDINGS Not one of the pseudopatients was detected by the staff, and seven of them were diagnosed as schizophrenic. They were all eventually discharged with a diagnosis of ‘schizophrenia in remission’, suggesting the mental illness could return at any time. The shortest stay for a pp was 7 days, the longest was 52 days, and the average stay was 19 days. Although no pp was detected by the staff, many of the regular patients suspected there was nothing wrong with them; 35 out of the 118 regular patients voiced their suspicions but they were ignored by the staff. A lot of the pp’s normal behaviour was interpreted by the staff as ‘abnormal’ and symptoms of their schizophrenia. For example, even their note-taking was interpreted as abnormal ‘writing behaviour’. The pp’s observed that even their life histories and medical histories were sometimes changed so that some past events were interpreted as examples of schizophrenic behaviour. Finally, pp’s were often treated as ‘objects’ rather than as fully human individuals. Very often their requests and inquiries were ignored by staff who treated patients, pseudo and genuine, as if they were invisible. CONCLUSIONS 1. The main experiment demonstrated a failure to detect sanity. The second experiment demonstrated a failure to detect insanity. Therefore, Rosenhan claimed that psychiatrists cannot reliably tell the difference between people who are sane and those who are insane. 2. Rosenhan suggests that psychiatric labels for mental illness tend to influence how a person is seen in a way that medical labels do not. And that everything a patient does is interpreted to fit that label once it has been applied. 3. Rosenhan noted that mental patients tend to be depersonalised and rendered powerless when they are in institutions. For example, their medical records are open to all members of staff; many of the toilets do not have doors; and staff members may treat patients quite brutally in front of other patients, but not when other members of staff are present. 4. Rosenhan suggested that instead of labelling a person as insane, we should focus on the individual’s specific problems and behaviours. In other words, we should treat the person and not the label. 20 HEMISPHERE DECONNECTION AND UNITY IN CONSCIOUS AWARENESS - Roger Sperry (1968) INTRODUCTION The human brain is divided into two hemispheres – a left hemisphere and a right hemisphere. The hemispheres communicate with one another by the corpus callosum, a bridge of fibres that connects them. Although the two hemispheres look similar, they have different functions. For example, the left hemisphere is usually responsible for language while the right hemisphere is better at spatial tasks, for example drawing and pointing at objects. This division of tasks between the hemispheres is called lateralisation of function. In patients suffering from severe epilepsy, surgery is sometimes used to severe the corpus callosum to prevent a seizure spreading from one hemisphere so the other. Such patients, whose hemispheres have been deconnected are described as having a split-brain. AIM Roger Sperry (1968) investigated the effects of hemisphere deconnection, in particular to demonstrate that each hemisphere of the human brain carries out different functions. PROCEDURE The participants in this study were 11 patients who had undergone deconnection of their cerebral hemispheres because they suffered from intractable epilepsy that could not be controlled by medication. These patients were therefore ‘split-brain’ patients. Sperry used a number of tasks in order to investigate lateralisation of brain function. The tasks were carried out in laboratory conditions, using specialised equipment and were highly standardised. The tasks all involved settings tasks separately to the two brain hemispheres. The performance of the ‘split-brain’ patients was compared with that of participants with no hemisphere deconnection (the control group). The study also makes use of the case study method. The case studies were in-depth investigations of the 11 participants. For example, in one task patients were asked to respond to tactile information. For example, a spoon was put into the patient’s hand without the patient being able to see what the object was. The patient was then asked to name the object. According to Sperry, if the spoon is placed in the left hand of a split-brain patient, he should not be able to name it because the object had not been seen by the right hand side of the brain. Similarly, Sperry predicted that if an object is flashed in the left field of a patient’s vision, he is likely to report he saw nothing. 21 FINDINGS As predicted by Sperry, when participants were presented with an image in one half of their visual field and then presented with the same image in the other half, they responded as if they had never seen the image before. In addition, participants were not able to describe an image presented only to the left side of their visual field. The image was either not noticed or just appeared as a flash. For example, two symbols were presented at the same time – a dollar sign to the left field of vision, a question mark to the right field of vision. Patients were then asked to draw and name what they had seen. They drew the dollar sign but named it as a question mark. Sperry also found that hemisphere deconnection did not affect the patients’ intelligence (as measured by an IQ test), nor did deconnection affect their personality. The effects of the surgery did affect the patients in that they had short-term memory difficulties, limited concentration spans, and orientation problems. CONCLUSION Sperry argued that his studies give considerable support to his argument of lateralisation of function, i.e. each hemisphere of the brain is specialised for the performance of certain tasks. The left hemisphere specialises in language tasks while the right hemisphere specialises in tasks involving spatial analysis. Sperry showed that each hemisphere can operate as a separate ‘brain’ if the whole brain is divided surgically. He also went on to argue that each hemisphere has its own perceptions, memories and experiences. EVALUATION A strength of Sperry’s procedure is that he combined cases studies of the ‘split brain’ patients with well-controlled tasks. This provided him with qualitative and quantitative information. This combination of methods allows for the reliable data gathered to be enhanced by the participants’ description of their personal experiences. A major weakness of the study was Sperry’s small sample – only 11 ‘split brain’ patients, but this was probably beyond his control because of the small number available. However, this did allow him to gather more in-depth data in the case studies. The 11 split-brain patients were the experimental group. The control group – people with no deconnection – could have been improved by using epileptic people who had not been deconnected. Finally, there is the question of ecological validity. In real life, people whose hemispheres have been deconnected use both eyes to compensate for any loss of function. 22 PSY 2 – APPLIED RESEARCH METHODS - INTRODUCTION & PRACTICE INTRODUCTION In this section of PSY2 you will be given two novel situations. You choose one of these situations and then describe how you would conduct research into the situation you have chosen. You are guided in the design of your research by these topics: method; reliability OR validity; ethical issues; ways of dealing with these ethical issues; sampling techniques; and methods of analysis. Here is how this section of PSY2 looks: SECTION C Answer either question 7 or question 8. You are reminded the focus of your response must be the application of knowledge of research methods to the novel situation. 7. You have been asked to investigate whether having a dog as a pet has a beneficial impact on the individual’s psychological health and physical health. Discuss how you would conduct research into this area, explain the design of the research in terms of: method; reliability OR validity; ethical issues; ways of dealing with these ethical issues; sampling techniques; and methods of analysis. (12) 8. You have been asked to investigate whether there are differences in the games that boys and girls engage in when they are in the school playground area. Discuss how you would conduct research into this area, explain the design of the research in terms of: method; reliability OR validity; ethical issues; ways of dealing with these ethical issues; sampling techniques; and methods of analysis. (12) When designing your research, make sure you 1) 2) 3) 4) 5) 6) 7) Explain the design of the research in terms of method; Explain how you would ensure the reliability of your research; OR Explain how you would ensure the validity of your research; Discuss ethical issues that might arise in your investigation; Explain how you would deal with these ethical issues; Explain what sampling techniques you would use and why Explain how you would analyse and display the data. 23 Identifying the Method Perhaps the greatest challenge in designing your research is your choice of method. Depending on the novel situation, you could choose to conduct a questionnaire survey, interviews, naturalistic observation, correlational study, or an experiment. If an experiment is appropriate, will it be a laboratory experiment, a field experiment, or a natural experiment? If it is an experiment, can you identify the IV (independent variable) and the DV (dependent variable)? And you will also need to choose and identify an experimental design – repeated measures, independent groups, matched participants. When you are deciding on your method, ask and answer these questions. 1) 2) 3) 4) 5) What’s the aim of this investigation? What would be a suitable hypothesis? Where will the research take place? Who will the participants be? How should the data be gathered? Now apply these questions to the following hypotheses and decide on the most appropriate method to investigate them. 1) 2) 3) 4) 5) Students learn more in the morning than in the afternoon. Girls watch more ‘soaps’ than boys. People remember emotionally-charged words better than emotionally-neutral words. Older people sleep fewer hours than younger people. Teachers give higher marks to attractive students than they do to unattractive students. 6) Boys are more aggressive than girls in the playground. 7) A-level grades improve as revision time increases. 8) Students who have a computer at home do better in exams than students who do not have a computer. 9) Good-looking people have higher levels of self-esteem. 10) Customers remember the faces of shop assistants who smile and make pleasant comments than shop assistants who do not. Ethical Issues You probably noticed that a number of the situations above involve ethical issues. Can you identify at least one ethical issue involved in each study, and how it could be dealt with? Ethical issues include: Participants must be protected from psychological or physical harm Consent/Informed Consent Deception 24 Right to withdraw from an investigation Anonymity and confidentiality Debriefing Follow-up counselling Sampling Techniques Let’s say you wanted to investigate if the boys in your school were more aggressive than the girls. In an ideal investigation you would include every boy and girl in the study but that’s impossible. The boys and girls in your school would be the target population, and you would select only a representative sample. There are different ways of selecting your sample. These include: opportunity sampling; volunteer or self-selected sampling; random sampling; stratified sampling. Explain how each sampling is carried out Describe one advantage of each sampling method. Describe one disadvantage of each sampling method. Identify an appropriate sampling method for each of the 10 novel situations above. Reliability – A Reminder There are two kinds of reliability: Internal reliability refers to the extent to which a test provides consistent findings. An IQ test that gave you a score of 130 on Monday and a score of 80 on Tuesday would clearly be unreliable. The split-half method can be used to test internal reliability. For example, you could split the IQ test into two sections. If the participant scored very differently on the first section compared with the second section, the test would not be reliable. External reliability means the test is consistent over a period of time. For example, an IQ test should produce the same results as it did last year. We often test reliability by using the test-retest method. Explain how you would ensure reliability when investigating each of the 10 hypotheses outlined above. 25 Validity – Internal and External Internal validity refers to the extent to which a test measures what it is supposed to be measuring. There are quite a number of factors that can undermine the validity of an investigation, and if internal validity is low, the results have little value. These factors include: participant awareness that he is taking part in an investigation; demand characteristics, investigator effects, experimenter bias – for example, the experimenter’s expectations affect the participants’ performance. Ways of dealing with these include the single blind design, the double blind design, and experimental realism. A pilot study, a small-scale trial, is often carried out to check the validity of what will happen in the full investigation. External validity refers to the extent to which the findings/conclusions of an investigation can be generalised beyond that particular investigation. There are different kinds of external validity. Ecological validity is concerns the extent to which our findings can be generalised to the real world and the extent to which these finds are representative of the real world. Population validity concerns generalising the findings to different people or populations. Historical validity concerns generalising the findings to people who lived at different times, e.g. modern times and medieval times. To test external validity we should try and replicate our study, using exactly the same standarised procedures, to check it produces the same findings. Explain how you would ensure validity when investigating each of the 10 hypotheses outlined above. Correlational Analysis Correlation allows the researcher to compare two variables where one is related to the other; for example, ice-cream sales increase as the temperature increases (a positive correlation), and umbrella sales decrease as the days get drier (a negative correlation). The correlation co-efficient is a statistical way to measure the relationship between two variables: +/1.0 means a perfect correlation while 0.0 means no correlation at all. Correlation allows predictions to be made (global warming’s here – order more icecream!) but it can never say that one variable causes the change in the other variable. In the 10 hypothesis, identify the investigations where correlational analysis would be appropriate, why it would be appropriate, and have a guess at what the correlation coefficient, if any, might be. 26 WORKED EXAMPLES BY STUDENTS Warning! These are not model answers. These are answers given by students. They are included here for you to read, discuss and think about. How well do you think each student has done? Are there things that are wrong? Or things that could be improved? Remember it’s understanding that helps you learn, not simply repeating what you have been told, no matter how well you have been told it. 1. You have been asked to investigate the attitudes towards dieting in young people from different backgrounds. The aim of my study is to investigate the relationship between young people’s background and their attitude towards eating and dieting. I would do a questionnaire survey and an interview to gather the information from the participants. The questionnaire would involve closed questions and forced answers to provide me with quantitative data. Using questionnaires is quick and cheap, and they can gather a lot of data from a large sample of participants. I would interview a sample of these participants, using an unstructured interview, to check the responses they gave on the questionnaire. This would provide qualitative data. I would check the reliability of my investigation by doing a pilot study first. This would check the questions I asked really were all about the backgrounds and the eating habits of the participants. I would make sure that my investigation could be replicated step-bystep and get the same results from the same target population. I would also interview the sample myself to avoid researcher bias. I would keep in mind any ethical issues that might arise. Young people, especially girls, are sensitive about dieting, so I would reassure participants that their confidentiality and anonymity would be respected. I would give each participant a number and I would not record any details that could identify particular participants. My investigation would start when I had obtained the participants’ informed consent. I would obtain my participants by using volunteer sampling amongst the members of the Sixth Form in my school. Volunteer sampling has the advantage of being easy and it gives you a variety of participants, but it can be biased because volunteers are not usually representative of the target population. I would pin up a notice in the Sixth Form common room and see how many volunteers I could attract. From these volunteers, I would select about 20 males and females from a wide variety of backgrounds. I would divide the participants into three groups, according to their backgrounds. I would analyse the quantitative/numerical data, using the measures of central tendency – the mean, the mode and the median (high scores correspond to the frequency of dieting). I would then display the data using graphs and charts. For example, a scattergraph would show the correlation, if any, between backgrounds and dieting habits. A bar chart would also allow the data to be assessed at a glance. 27 2. You have been asked to investigate the suggestion that small children playing outside do not wander far away from their mothers. The aim of my study would be to see how close children stay to their mothers during play outside. My hypothesis would be that children playing outside stay close to their mothers. I would use naturalistic observation as my method. This has the advantage of studying behaviour where it naturally occurs and in situations where the variables cannot be manipulated. It has the disadvantage that the researcher cannot control any extraneous variables that might occur. In this case, I would observe children, under 5, with their mothers in a popular local park near where I live. To ensure reliability I would make up a Table to keep a record of my observations. This might include the child’s distances from his mother, the number of times he achieved these distance, and the number of observations. This would provide quantitative data. I would also do a pilot study to test the reliability of everything I planned to do. I might also use the test-retest method and do the same observations a week later to check my results. There are always ethical issues in observing people. It would be unethical to watch mothers and children in a park without first obtaining informed consent, and potential participants would have the right to decline to take part in the study. I would also ensure the participants knew their anonymity and confidentiality would be respected, and I would take no personal information that could identify the participants. My sampling would be a combination of opportunity sampling and volunteer sampling. I would have to use the mothers and children who happened to be in the park at the time of my investigation, and I would have to ask potential participants to volunteer to take part when I invited their informed consent. One limitation of this approach is that there might not be typical cross-section of participants present at the time of my investigation, and playing in a park might cause different behaviour from playing outside in different conditions, for example at the swings. Because I have secured quantitative data, including the ages of the children, I would be able to use the measures of central tendency, the mean, the mode and the median. This might show that older toddlers are more likely to wander further away from their mothers than younger children. I could also use scattergraphs and bar charts to display the results. My findings might also be useful in measuring levels and kinds of attachment between mothers and children. 28 3. Most students say they feel very stressed during examinations. Some students claim they feel little or no stress at this time. Students claim that stress can affect their examination performance. How would you investigate whether stress levels affect students’ performance? This investigation would examine whether stress levels affect students’ performance during examinations. My hypothesis would be that examination performance deteriorates as stress scores rise. This would be a directional hypothesis as I am predicting the direction of the outcome of the investigation. After I obtained my sample, I would measure each student’s stress level just before he/she took each examination. After the examinations, I would obtain each student’s examination scores. This means I would have two scores (stress levels and scores) for each student. I would then use correlation analysis to measure the relationship between the co-variables - stress levels and examination performance overall. To ensure the reliability of my investigation, I would measure stress levels by using the galvanic stress response (GSR), which is a measure of ANS (autonomic nervous system) activity. This would give me a numerical score for each student (quantitative data). I would also use a questionnaire to let each student assess his/her own stress levels. It would be a good idea to run a pilot study to check my method was reliable. I would obtain a random sample from the students in the Sixth Form at my school. This would everyone an equal chance of being selected. I would put the names of everyone in the Sixth Form in a hat, and the first 20 drawn would constitute my sample. Of course, I would need informed consent from each student/participant taking part in my investigation. Informed consent is ethically important, especially when young people are involved in an investigation. The BPS ethical guidelines suggest that consent must be given for all studies unless there is a good reason for deception. In this case, I would explain fully (using a standardized notice) to ever participant the nature and procedure of my investigation. I would also get permission from my head teacher, and I would ask the participants to sign an informed consent form. When I had obtained all my data, I would produce a scattergraph to show the relationship between stress levels and examination performance. The line of best fit would show at a glance if there was a negative correlation between the two sets of scores. I would also prepare a summary table showing the scores. I would then use an appropriate statistical test to calculate the correlation coefficient, and see if the correlation was significant or not. 29 4. In recent years there has been a great emphasis on encouraging healthy eating in schools. How would you investigate whether the students in your school have healthy eating habits? My aim would be to investigate whether students in my school have healthy eating habits or not. In order to investigate this I would construct a suitable questionnaire, and I would use the questionnaire to carry out my survey. The advantage of using a questionnaire is that you can obtain a lot of data quickly and cheaply. They can provide large samples, and the researcher does not have to be there when they are being completed. One disadvantage is that participants may give you the answers they think you want, or they make give you totally false answers (the s-called ‘screw you’ effect. I would use closed questions with forced answers in the questionnaire. For example: Do you smoke? Never – Occasionally – Frequently – Far too much. And: How many portions of fruit do you eat every day? 0 – 1 – 2 – 3 – 4 – 5. It is much easier to analyse data like this than qualitative data I would get from an unstructured interview. To check reliability, I would carry out a pilot study, a mini-version of the real thing. This would check the design of the questionnaire, and make sure the questions were clear and unambiguous. I would also make sure there were no upsetting questions in the questionnaire. I might also use the test-retest method by asking my participants to do the questionnaire again a week later and then compare the responses. There are usually ethical issues when asking people for personal information, for example about their eating habits. As mentioned, I would make sure there were no upsetting questions in the questionnaire. I would also ensure that participants did not put their names on the questionnaires, and I would explain their rights of confidentiality when I was obtaining their informed consent. I would use a volunteer sample to select about 50 participants. I would ask teachers from Years 1 to 5 to ask for 10 volunteers each to take part. The teachers would also explain the nature and purpose of the investigation, using my standardized information. The teachers would also collect in the completed questionnaires and return them to me. I would use a range of graphics to analyse and display my results. For example, I could use pie charts and bar charts to display the results. I might also publish my results on the computer network system to show how healthy – or not – our school is. 30 5. There is a lot of evidence to suggest that giving rewards encourages behaviour. How would you investigate the suggestion that rewards encourage desirable behaviour in your school? The hypothesis for my investigation would be that rewards encourage desirable behaviour. I would select a directional hypothesis because previous research suggests the hypothesis will be supported by my study. Basically I would conduct a field experiment in my school. This would involve two groups from Year 7, Group A and Group B. These groups would come from the same ability band, and they would be independent groups. Both groups would be set the same task, for example memorising the capital cities of 10 European countries. Group A would not know that Group B were promised a reward if they did very well in the task. Both groups would have 30 minutes to memorise the capitals, then they would be tested for recall. To ensure the reliability of my investigation, I would ask the class teachers to carry out my procedure in class. I would also ask them to follow my standardised instructions. This might help reduce researcher bias. I would also choose capital cities the students were not likely to know, and I would test these out on a similar Year 7 class first. I would make sure that my procedure was easy to replicate step by step. There are a number of ethical issues in my investigation. Obviously I cannot get informed consent, so I would use presumptive consent; this means asking a group similar to the real groups if they would be willing to take part in such an investigation. If they are willing, I can presume the real groups would consent. I am also using minor deception in my study so I would debrief all of the participants at the end of the study. I would also reward Group A to make them equal with Group B. My investigation would use opportunity sampling because I would take the opportunity of using two Year 7 classes in my school. Opportunity sampling has the advantage of being easy but it may not be representative of the target population. For example, Year 7 students may react to promised rewards more readily than students in the Sixth Form. But I would try to match my participants by choosing two classes from the same ability band. My investigation would provide numerical data so I would calculate the measures of central tendency for Group A and Group B. I would calculate the mean, the median, and the mode. In this case, the mean is probably the most significant measure because it uses all the raw data. However, it can be skewed by extreme scores, in which case the median would be better. I would also display my findings on a bar chart so that the results can be assessed at a glance. 31