3.3.3 contemporary study Flashcards
What was the contemporary study
brendgen et al 2005 agggression in 6yo twins
What was the aim
to find out if there is a difference between physical and social aggression in six year old school children by surveying the teachers and classmates. In particular, to see if physically aggressive children are also socially aggressive and to investigate whether the link is down to genetics or social situation by comparing MZ and DZ twins
What was the Procedure
sample: 322 twin pairs tested, but complete data gathered on 134 twin pairs
longitudinal: enter the study when born and carried out
independent variable: the aggression scores for identical twins Emzee and the aggression scores for non-identical twins DZ, and the correlation between three teacher ratings and four peer ratings
It was a natural experiment and the teachers questionnaires asked them to write each child Six statements and the schools for social aggression and physical aggression when added together to produce two overall scores
What were the results
he carried out a chi squared inferential test, comparing the ratings from the teachers and peers. The differences were not significant and this suggests the two sets of ratings can be combined together. There was a moderate link in that those showing social aggression also showed physical aggression. Identical twins correlations for physical aggression based on teacher and peer ratings, we are nearly twice as high for same-sex non-identical twins as the same six identical twins, suggesting a strong genetic contribution to physical aggression. Identical and non-identical twins were similar in the correlation for social aggression, which suggests that as both shared environment within the one another, social aggression might come from a shared environment.
But the teacher did Right boys as more physically aggressive and the girls more socially aggressive
What were the conclusions
There seems to be a strong genetic component of physical aggression: 50 to 60% can be linked to jeans, there seems to be a strong environmental influence on social aggression, children who are physically aggressive are also more likely to display social aggression, suggesting an interaction between jeans in the environment and so physical aggression is mostly nature for social aggression is mostly nurture
Evaluate
Generalisability: he used a large sample so unusual children with very high or low levels of aggression could be averaged out and the study only looked at six-year-olds. In some ways this is a representative age group because they are going through the shift from physical aggression towards social aggression, but in otherwise it may not be representative because some children will be slow developers and others will be fast developers
reliability: are use a establish questionnaire to measure aggression that can be easily replicated making a study reliable, to research is visited each classroom suggesting the study had interrater reliability is, there was a strong correlation between teacher and peer ratings suggesting the schools are reliable but the language differences might make the study less reliable, questions translated into another language might have slightly different meanings
Application: if social aggression is strongly linked to environment, it must be possible to reduce the worst effects of verbal bullying by using early intervention e.g. classes and workshops. And if friends and family or a big influence of social aggression, it suggests that educating parents into better ways of handling their children and being better role models might prevent children from being socially aggressive with their own friends
validity: twin studies are a valid way of studying nature and nurture, as a natural experiment the study cannot show cause-and-effect
Ethics: the parents of the twins agreed for their children to be in study so presumptive consent was given by a responsible adult but study does get children to look at pictures of their classmates and judge them and this might have a bad impact on friendships
