3.2 methods (biological) Flashcards
1
Q
what are twin studies?
A
- studies done to compare twins
- DZ twins share half genes and MZ share all of their genes
- twins tend to be raised in the same environment
- if monozygotic twins are more similar than dizygotic twins, genes are involved
-eg study is brendgen
2
Q
what is a strength of twin studies as research methods?
A
- correlations allow investigation of influence of genes
- assumed both MZ and DZ twins share the same environment
- only difference is genetics
- therefore, allows us to investigate effect of genetics on behaviour that is otherwise practically and ethically impossible
3
Q
what’s a weakness of twin studies as a research method?
A
- overestimate genetic influence
- MZ twins have more similar environments than opposite sex DZ twins, treated more similarly
- therefore, one of estimated similarity is due to shared environments
4
Q
TWIN AND ADOPTION STUDIES ARE ADDED TO ‘3.3 studies’ INSTEAD BY ACCIDENT
A
5
Q
what are correlations as a research method?
A
- researchers use correlations to see if a relationship between two or more variables exist
- positive correlation = when one variable increases, the other also increases (ORA)
- negative correlation = when one variable decreases, the other one increases (ORA)
- finding a correlation between two variables doesn’t mean there’s a cause/effect relationship
6
Q
what’s a benefit of using correlations as a research method?
A
- may be the only method available where manipulation is impossible
- certain factors such as upbringing or traumatic experiences are variables practically or ethically impossible to manipulate
- therefore, correlations are the only method to statistically investigate relationship
7
Q
what’s a limitation of using correlations as a research method?
A
- may be intervening variables
- a third variable might be the cause of the relationship between two variables — give an eg
- correlations has no ability to predict the existence or effects of intervening variables
