Outline and evluate one socio-psychological explantion of aggression

One socio-psychological theory of aggression is Social learning theory. The social learning theory of aggression suggests that through vicarious learning, we observe and imitate an aggressive act that is rewarded. Normally, people would imitate an aggressive act if a role model was the one doing the action or if they are similar to us in some way (Duck). Imitation also needs the person to have the motivation, self-efficacy and positive or nor retention of past aggressive acts. The environment is also important in determining whether or not imitation will occur. In a darkened, aggressive, loud and confusing nightclub in which people have had much to drink, someone may be more prone to copying aggression. Or differently, a fearful person may be too afraid of retaliation to copy an aggressive act in an unfamiliar setting.
In Bandura’s Bobo doll study, children watched an adult act aggressively towards the Bobo doll. They then either saw the adult get rewarded, punished, or neither. The children were then let out to play with the Bobo doll. The condition in which the children watched the adult get rewarded displayed the greatest aggressive acts. However the other two conditions displayed no aggressive acts. This shows that imitation only occurs when children have a positive, rewarded mental representation of aggressive behaviour. A weakness with the Bobo doll study is that it does not could for individual differences. Children may have naturally been more aggressive in one condition rather than the other. Being children, social learning theory is hard pushed to then generalise to adults who have a much more developed and experienced representation of aggressive behaviour.

However, the study does have real life applications. The Jamie Bugler case, in which two young boys horrifically murdered a toddler, apparently supported this explanation. The boys admitted to watching Chucky and imitating the violence they saw. Although this seems to be shocking vicarious learning and was the explanation given, one psychologist found no link between SLT and the crime. Moreover, the perpetrators were deeply disturbed and therefore such a simple and natural demonstration of SLT cannot be attributed. Phillips also found that SLT has real world applications in America. After a wrestling match, homicides increased, perhaps showing imitation of the violence shown on the media. However this is merely correlational data and therefore other factors may influence homicide rates such as: team rivalry, hostile environments and Deindividuation.

Altgough championed for its universalised and cultural variations, SLT can be seen as an imposed ethic on non Western cultures. Wolfgang’s “culture of violence” study showed that according to different cultures, aggressive and non-aggressive behaviour models varied. He gave the example of the !Kung Sang men who are completely non-violent and look down upon aggressive behaviour whereas in Western society, aggressive behaviour is a sign of manliness. Therefore in some cultures, the imitation of violence is simply not there no matter the reward.

Studies into SLT are also limited, meaning that further experimentation is required to gain more detailed information. This poses an ethical problem, imitation of aggressive behaviour is not something to encourage, especially in children, and is not protecting participants from harm.

Moreover, the study is incredibly deterministic, suggesting that people will copy rewarded behaviours without giving any explanation as to how or why. In this sense, it is also reductionist, reducing complex psychological and biological behaviour into imitation. Runciman claimed an alternative to SLT, that deprivation caused aggression, as did Dollard- environmental factors were the reason for aggressive behaviour. 

Discuss research into factors influencing attitudes to food and/or eating behaviour. (24 marks)

Discuss research into factors influencing attitudes to food and/or eating behaviour. (24 marks)

Mood is one factor influencing eating behaviour. Garcia conducted a study in which 38 participants were assigned to two conditions. In the first, they watched an upbeat, comic film and in the second they watched a sad film. In both conditions, grapes and popcorn were provided as snacks. It was observed that in the sad film condition, 31% more popcorn was consumed than in the upbeat film- opting for grapes. Garcia concluded that the calorific, sweet food jolted the person into a state of euphoria, whilst those already in a good mood chose healthy snacks to prolong their good mood. There are some methodological issues surrounding this study. Firstly, popcorn is a typical cinema food which may have meant that higher quantities of it were consumed due to that association. Moreover, individual differences are likely to pose a problem- some may simply prefer popcorn. To combat this, perhaps a repeated measures design would have been more appropriate, as participants are likely not to ascertain the study because the dependent variable is not particularly out of the ordinary. Moreover, other factors may have influenced eating behaviour in the study- for example what time of day it was and people’s eating habits and timings. This may reduce the internal validity of the study. 

However, it is shown that by levelling out mood through medication, comfort eating is reduced. This has real world applications in patients suffering from bipolar- a mood disorder- who are likely to be overweight and are prescribed mood altering drugs such as lithium. Although this does support that mood does influence eating behaviour, perhaps it could only be prescribed to major mood changes and not ones we experience perhaps dozens of times a day (and we know this doesn’t influence our food behaviour). Moreover, it is culturally biased. Mood cannot be afforded to influence eating behaviour in places such as Sub Saharan Africa. Therefore it could be said to be a factor only in affluent, Western societies and not a universal attributer.

Another factor influencing attitudes to food is culture. Ball and Kennedy followed (not literally!) 14000 women in Australia and found that the more time the women spent in Australia, the more their eating habits coincided with those women who had been born there. This shows that eating attitudes and behaviours are influenced by the culture we live in and we adapt to the environment- acculturation. This research perhaps highlights but does not explain that there could be an evolutionary explanation for acculturation, it would aid the survival of those women to begin to display the same eating attitudes and behaviours and aid social cohesion. We have still retained this ability to adapt to our environment and food availability/culture. However, it is endocentric, and therefore this study cannot be generalised to men. There may be social factors involved which determines whether different genders respond to acculturation differently or whether it is universal. Moreover, in all cultures, food is subject to availability and our preferences depend on this and could be shaped by this.

Social Learning Theory in terms of eating behaviour and attitudes states that these are observed and imitated from our parents. Brown and Odgen found a correlation between the child’s motivation to eat, body dissatisfaction and snack intake and the mother’s motivation, dissatisfaction and intake. This suggests that the child has observed and imitated the mother. Birch and Fish also found that the best predictor for a child’s eating habits is the mother’s food constraint and anxiety about the child being overweight. However this is reductionist. The correlation may be down to many other things such as genetics. We know that anorexia is more likely to manifest in children with a parent who previously suffered. It also doesn’t measure or mention the father’s eating habits and what influence this has on the child’s development (especially if a family consists of a single dad and his child, for example). Therefore it has a gender bias. The media, however, is an active example of SLT and proves that it is an influencing factor - people’s attitudes on food are known to be effected by observing and copying adverts, for example, and celebrities following specific diets. 

Discuss Explanations for the Failure and success of dieting

Discuss Explanations for the Failure and success of dieting

People diet in order to achieve cultural ideals on body weight and respond to body dissatisfaction. K    found that over 89% of the female population had reduced their intake at some point in their lives to lose weight. A successful diet is supposed to constitute as losing 10% of body weight and maintaining weight loss for at least a year. One way of ensuring success in dieting is to focus on the detail of the food rather than the numbers/nutritional value and the boredom surrounding dieting foods. Reddens conducted an experiment wherein 130 people were directed into two conditions. In one conditions, they tasted jelly beans named with numbers and in the other they tasted jelly beans with a flavour as a name i.e. ‘cherry’. They then filled out a questionnaire about the task’s enjoyability. The group who were given a flavour were less bored with the task than the group given a number. This suggests that group one had focused more on the details and flavours of the food and had enjoyed it more. This can be reflected into dieting, with detail of the restricted/repetitive foods alleviating boredom that leads to the failure of dieting. This study was very reliable, variables being easily controlled in a laboratory study. A weakness with this study is that jelly beans are usually a more enjoyable food and so perhaps a longitudinal study with diet food and calorie numbers may be a more realistic, natural study away from the laboratory, controlled nature of Redden’s study. Another component for the success of dieting is support and, again, enjoyability. This has wider world implications in weight loss groups such as weightwatchers. Compared to self-help, weightwatchers was more useful and successful than self-help and also maintained a stable weight for linger, suggesting that a community-like, encouraging environment is important (Miller).

The boundary model starts to explain the failure of dieting. Herman and Polivy showed that a diets range between hunger (the drive to eat) and satiety (feeling of fullness) is much wider than those not dieting and takes more food to reach satiety. Dieters, when they often breach the satiety boundary eat until they feel full and then continue, the “what the hell” phenomenon. In dieters, essentially, they take longer to feel hungry and it takes more food to satisfy. Wardle and Beats conducted a 7 week longitudinal study in which 29 overweight women were subject to one of three conditions; a dieting condition, exercise condition or no treatment. They filled out a questionnaire on eating habits and appetite at 4 weeks and 6 weeks. Wardle and Beats found that the dieters ate more, showing that in dieting conditions, the satiety boundary is likely to be overstepped by overeating to compensate. This may mean that for those overweight, exercise is a better option than dieting. This may also be true psychologically, with the continual failure of dieting manifesting into depression in obese individuals. This study does face issues with social desirability, being about weight and eating behaviours- things many women feel ashamed or embarrassed about and may not be honest in their questionnaire. Moreover, its small sample size of obese individuals cannot be generalised to the public. This may be because, for example, they suffer from eating disorders such as binge eating which may affect their intake.

The restraint theory suggests the more you deny yourself the food you wish, it leads to dis-inhibition which makes you overeat (Herman and Mack). Soetens supported this theory, when dieters suppress foods it almost had a rebound effect and led them to think more about food. Food became more attractive. Odgken questions the theory of restraint and the overeating consequences. He uses the example of anorexia, which the restraint theory does not explain this. Those suffering from the disease continually restrict to a dangerous level and do not eat. A response to this criticism is that it is a mental illness and the anorexics have no choice but to starve. Moreover,  this is shown in the role of denial in dieting, another influencer of failure. This model shows that the more you deny yourself something, the more you think about it- called Wegner’s ironic process of mental control. Wegner asked participants to either think of a white bear or not to think of a white bear. Those who were told NOT to think of a white bear rang a bell more often, showing that being denied to think about something led to inevitable over-thinking of it. Anorexics tend to become obsessed with food whilst during continual denial, supporting this. Keys fed his participants, male Korean conscientious objectors, half of their daily intake for 12 weeks. Although they lost 25% of their body weight (more than successful for dieting), they became obsessed with food and many became binge eaters. This shows that restriction led to obsession and overeating and changed the behaviour and attitudes of an individual. However, this study is extremely unethical-being conducted 60 years ago- and cannot be replicated; at least with humans. It was also an ethnic group of Koreans, which have cultural differences to us in terms of food. Another study even found that Asians were more prone to obesity, and that Asian girls are the group most likely to suffer from bulimia (an eating disorder constituting of consuming a large amount of food and then purging). This could indicate a tendency towards lowered food control and impulsivity or a cultural tendency. This study, however, does explore eating behaviour in males, lacking in other studies surrounding failure/success of dieting and affecting generalisability.

Success or failure of dieting could have an alternative biological explanation. LPL is a calorie storing enzyme which, if you are genetically inclined to have more of, may make it easier to regain lost weight. If weight loss is occurring, the gene becomes active and starts producing more as a response.

23/24 Outline and evaluate the role of genetic factors in aggressive behaviour (24 marks)

Outline and evaluate the role of genetic factors in aggressive behaviour (24 marks)

The claim that aggression can be inherited through genes has been studied by a large number of psychologists. Twin studies have been particularly useful for exploring this biological explanation, and has allowed psychologists to look chiefly at genes; especially in monozygotic twins. Rutter found a higher concordance in aggression for MZ twins than DZ twins, suggesting that the more similar the genes are, the more likely they share genetic behaviour such as aggression. Coccaro found that nearly 50 % of the variance in direct aggressive behaviour in adults was attributed to genes and 70% of verbal aggression. However, this research also contradicts the role of genetics in aggression, as it gives equal weighting to environmental factors, which the other 50% of the variance is attributed to. This briefly outlines the gene-environment interaction approach, with a genetic predisposition reacting with the environment to influence aggressive behaviour. Adoption studies have also helped to differentiate between the complicated contributions of environment and heredity in aggression. If the adopted child and their biological parents display aggressive behaviour, it is likely that genetics play a stronger role than upbringing in a different environment Hutchings and Mednick studies 1400 adoptions in Denmark and found that a significant number of adopted boys with criminal convictions had biological parents (usually fathers) with criminal convictions. This supports that genetics influence aggression, as there is evidently a correlation even when separated from biological parents and the same environment. There is a problem that the only aggression measured was criminal convictions however, as it may not have picked up on antisocial behaviour not caught. In fact, with only studying criminal convictions, the psychologists could have ignored those who are arguably more intelligent and aggression- not having been caught and getting away with the crime.

There are some problems with twin studies. The first being that although MZ twins have a higher concordance rate for aggression in comparison with DZ twins, the concordance rate is never 100%. This suggests that genetic factors are not the only factors for aggression and environment does play a part. A predisposition for violence, but a disciplined and supportive home environment may stop this behaviour being a problem. Another problem is that MZ twins look exactly the same, and share the same biological makeup. This would affect how society treats the twins, perhaps the same way. In this instance, DZ twins would be treated more like individuals, and would therefore show more variance in their behaviour.

With both methodologies, criminality may be studies more than aggression, which affects internal validity. This means that the study fails to differentiate between violent and non-violent crime; an individual may have a conviction for fraud and placed in the same category as an individual in prison for manslaughter. Another issue is that habitual violence may be a better indicator for aggression, but again is placed in the same category as a one-off crime (a person who became aggressive once after consuming alcohol and bumping into someone they both had a mutual hatred for each other). Mednick et al found the biggest effect in their study was for non-violent crime. Brennan, however, compared the criminal history of adopted males and their biological and adoptive parents. They found that genetic influences were significant in cases of property but not violent crime. This piece of research shows that a crime personality may be inherited rather than aggressive behaviour. Being in a demonstratively moral and supportive environment teaches children not to be aggressive instead of becoming desensitised to it in a genetically likely household with many convictions.

Gender bias has also been criticised in the study of the role of genetics in aggression. Button et al found that the genetic heritability of aggressive anti-social behaviour was much higher for girls than boys (this was not the case for non-aggressive anti-social behaviour such as truancy). Button’s research indicates that heritability is stronger in women than men when it comes to aggression, and that more research would need to be taken for females. This may also explain the lower concordance in same sex DZ twins.

Other psychologists have explained the genetic link to aggression with a single gene- the MAOA. This warrior gene is linked with aggression, with lower levels increasing aggression. This may be dues to the role it has on regulating the metabolism of serotonin on the brain, with lower levels increasing aggression.  Brunner studied a Dutch family with the males showing high levels of violence (convictions and high antisocial behaviour levels). The study found abnormally low levels of MAOA, showing that deficiencies cause aggression. This study is culturally bound, and may not be demonstrative of the link between aggression and genes around the rest of the world. However, a gene-environment explanation may carry more weight. Caspi conducted a meta-analysis with 500 male children. He found that low levels of MAOA in the children did concord with antisocial behaviour, supportive of this explanation, however only if maltreated as a child. This shows that social environment plus genes influences behaviour, rather than just one or the other. Moffat found a similar conclusion. By examining abuse, convictions, violence and antisocial behaviour in 422 males from New Zealand, low levels of MAOA correlated with the risk of being convicted but again, only if they had suffered abuse. All of these studies are based on male aggression, with no incidences of female aggression. This is a weakness, which means that genes can only be shown to influence aggression on men.

Research into MAOA on aggression, like twin and adoption studies, focuses on individuals who have been convicted of violent crimes. This means that the studies only involve aggressive individuals who have been caught- who may tend to be low-intelligence individuals. This may explain why many studies fail to find evidence of genetic influences on aggression. They also fail to explain cultural differences which suggests that genetics are not the only factors in aggression, otherwise it would be universally correlated. In this way, the MAOA gene’s studies are ethnocentric, unable to be generalised to other countries.

However, research into this gene may be useful for society and the individual. Morley and Hall suggest that information from genetic screenings could be used to devise new treatments for personality disorders that have been identified as risk factors for criminal behaviours. The treatment would be able to lower the risk of the person being put in prison, and create a safer society. However, there are ethical weaknesses with this. This is rather deterministic, stating that the person will be aggressive after being labelled with MAMO deficiencies and is not pleasant for the person. Because it is their genetic makeup, this may seem like their personality is being altered when there is really only 50% variance linked to aggression. It could be useful when environmental factors pose a risk for those also with low levels of MAOA.

Many studies of genetic influences on aggressive behaviour rely on self-reports and these studies tend to show that there is a genetic link for aggression. However, observational studies have not been consistent. Miles and Carey found less genetic influence on aggression through observation than with self-reports in a meta-analysis. A replication of Bandura’s Bobo study using twins found no difference in MZ and DZ twins, suggesting that individual differences in aggression were more of a product of environmental influences than genetics (Plomin). This research suggests that many studies into MAOA are inconsistent, and the link found is unpredictable. Morley and Hall argue that genes associated with aggression only poorly predict the likelihood that an individual will display aggressive behaviour. The presence or absence of environmental factors can’t be identified in a genetic text, making the prediction of aggression even less likely. Perhaps a gene-environment interaction is a better explanation, with those who are predisposed genetically and brought up in a low socio-economic background more prone than those predisposed and brought up in a higher socio-economic environment in an area with low crime rates. If both genes and environment are not good predictor, then used in synchronisation will increase the accuracy.

The role of genetics is reductionist, as is states that aggression is caused by a single gene to make it easy to test. It ignores complex biological factors as well as psychological and environmental factors. For example, MAOA decreases low serotonin levels. Low serotonin levels are correlated with increased risk for depression. It could be that they are testing depression in males, as aggression and violence are symptoms of male depression (especially if they had suffered mistreatment as a child).  It is also determinist, showing that aggression is determined by our genes and that we can treat people with “faulty” genes. The biological approach ignores free will and this reduces individual responsibility for aggression, a significant problem when addressing an issue which is frequently dealt with in court and is harmful to society. 

24/24 Outline and Evaluate Research into Institutional Aggression

Outline and Evaluate Research into Institutional Aggression (24 marks)

Institutions are ‘structures and mechanisms of social order and co-operation governing the behaviour of a body of individuals’. Examples of these mechanism are prisons, hospitals, schools and psychiatric hospitals where large numbers are brought together and their behaviour is governed by a set of rules. Some psychologists believe that aggression within institutions occur as a result of the social context influencing their behaviour and willingness to inflict harm rather than the individual themselves. Zimbardo suggested that we should consider the factors in the situation that cause acts of evil rather than suggest people are ‘good’ or ‘bad’. This was evident in his famous prison study (1971) where ‘normal’ people such as the guard, Hellman, became extremely violent towards the prisoners because of the situation. In this experiment a sample of 24 male participants was used and each participant was given a full physical and mental evaluation to ensure full health. Participants were then randomly allocated into roles as guards or prisoners. As the participants started to get into their roles the guards became more and more controlling. Guard Hellman was found to be one of the most aggressive officers. Before Hellman had entered the experiment he had described himself as someone who loves all people. Zimbardo concluded that it was the 'situation' that had made Hellman behave the way he did. This research supports the situational explanation of aggression because it emphasises how people will act aggressively when they are in a certain situation. Paterline and Peterson put forward that the stressful conditions of the institution (overcrowding, unexperienced staff) leads to the institutional aggression that Zimbardo found in his experiment. This overcrowding, loss of rights, and powerlessness causes aggression (Steffensmeier) and is due to the patient/prisoner becoming deprived. The deprivation model suggests that this factor is the main cause of institutional aggression, with a focus lack of the needs and basic materials of the people in these establishments being severely deprived (i.e. outside contact in prisons, rights, freedom) and reacting with hostility to cope/regain these things.

Sykes investigated prison aggression in particular and found that innate behaviour is a response to the problems of adjustment posed by deprivations or ‘pains’ of imprisonment. The five deprivations were liberty, autonomy, goods/services, heterosexual relationships and security. These deprivations cause stress and frustration in prisoners and aggression is a response to release this stress. Moreover, this aggression also enables a prisoner to gain control over the oppressive social order imposed upon them. McCorkle et al (1995) conducted a large-scale study of more than 371 US state prisons to investigate the effects of environmental influences of inmate violence rates. The variables they measured were crowding, security level, officer-to-inmate ratio, program involvement, size of institution and unemployment rate of the local area around the establishment. McCorkle found that the white-black guard ratio were positively correlated to assault rates, suggesting that institutional violence is partly a racial issue and not deprivation. However, it may be that the prisoners are deprived of ‘respected’ prison guards, with white, racist prisoners being controlled by black guards of whom they don’t respect and vice versa. The study also found that poor prison management led to individual acts of violence, proving the deprivation model- with aggression being implemented when the prisoners are denied a stress-free experience- and that the removing of privileges triggered outbursts of individual violence. The more prisoners were involved with education and skills programmes, the more the decrease in institutional violence suggesting that the more prisoners were given things the less they were deprived and prone to violence. Interestingly though, overcrowding did not influence inmate-on-inmate assault rates disproving the deprivation model and showing the study to lack internal validity. Nijman also found that increasing personal space didn’t reduce the levels of violence among patients in psychiatric institutions, suggesting that this factor isn’t specific enough in its objectivity. In McCorkle’s study, the very large sample is a significant positive of this experiment, and the real-life quality and nationalism is another- the realism making it easier to generalise. Apart from the study’s findings half disproving the study, the array of variables that were measured create a rounded and comprehensive study that has accounted for the many major factors that may influence institutional aggression. However, despite its nationalism, it’s still culturally biased to the U.S.A and may not reflect prison environments from around the rest of the world. It is also supposedly androcentric, with female prisons not being mentioned and again, making it hard to generalise.

The deprivation model has much research support. Wilson studied Prison Woodhill in the early 90s and changed the environment, making it less claustrophobic, played radio sound to mask the prison sounds and reduced the too-hot temperature. These changes virtually eradicated assaults on prison staff and inmates, proving that small considerations and amendments on basic deprivations can improve violence rates. This study was conducted in a period where the situational factors in prisons would be much different to todays and therefore can’t be relied upon completely. Gaes and Macuire’s research also found that the deprivation of space, or overcrowding, led to prison violence.

There is also research on unexperienced staff. Davies and Burgess found that the length of service by prison staff affected assaults, where more experienced officers were less likely to suffer assault. In a hospital setting, Hodgkinson found a similar result. With trainee nurses more likely to suffer violent assaults than experienced nurses. These studies demonstrate that the person’s deprivation of experienced staff which, in turn, reduce the stress of the experience and make the adjustment easier, led to prison violence. However, it could be said that the inexperienced staff were easier to target their pent-up derivational aggression onto. In this case, inexperienced staff are not a deprivation for prisoners but are the easiest recipient of institutional aggression due to deprivation.

Individual differences contend with the deprivation model and pose a weakness. Kane and Janus suggest that people with serious criminal convictions are more likely to be aggressive. This suggests that the reason why individuals have been incarcerated may be the determining factor for institutional aggression. Crimes such as fraud are non-aggressive, and those who are in prison because of these crimes are less likely to become aggressive rather than those who have been convicted of assault under derivational circumstances. Poole and Regoli found that pre-institutional violence was the best indicator of violence in a juvenile detention centre regardless of situational factors. It could be said that these prisoners prone to institutional violence have initially been deprived of things (parental love, role models, attachments, basic rights and education) in early childhood or life which has led them to be imprisoned. With this in mind, it is only logical that these people will continue to be violent in a prison environment, which further deprives them of basic rights and materials to be happy. It is therefore only logical to reduce deprivation in prison to reduce violence in institutions and outside. Bastoy Island Ecological Prison in Norway is evidential. Run like a society, fostering respect and focusing on reintegrating inmates into society, with staff with social work qualifications and decent housing arrangements. The executive of this prison looks at “this place as a place of healing, not just of your social wounds but of the wounds inflicted on you by the state in your four or five years in eight square metres of high security”- or in other words deprivation in early life; and deprivation in strict institutions. This seems to have worked, with a 16% reoffending rate compared with 70% across the rest of Europe. This does have some ethical issues, with victims of the crime unhappy with a punishment that doesn’t sound too unpleasant and may find it unjust but in the long term, it is positively looked at as helping society in the long-term.

Another weakness with the studies on the deprivation model is that it is gender-biased. Male aggression is predominantly measured rather than female violence in institutions. Further research would need to be conducted to see if there is a biological factor which influences aggression. For example, males could be more prone to violence in prisons due to biological differences to females. The research also tends to originate in US prisons, and therefore the findings cannot be generalised to other institutional settings around the world.

This model is deterministic as it suggests that all people will be aggressive if they feel deprived. However, research has shown that not every person will choose to be aggressive within an institutional setting, suggesting that we do have free will. People respond to deprivation in different ways. It is also reductionist as it reduces aggressive behaviour down to feeling of deprivation- it could be said Deindividuation is the reason for institutional violence. This reductionism therefore suggests that people are blank-slates when they enter the institutional setting as it ignores the role of people’s life experiences and traits as well as their biology- some people are more chemically prone to violence than others. However, the research into deprivation can be used to reduce aggression levels in institutions. By improving the conditions of the situation, the levels of aggression should reduce. This promotes wellbeing for the staff and the patients/prisoners. The research is also adaptable to a variety of institutional settings such as schools. This model could explain why some children in schools are more aggressive than others in the playground.