PSYC 305 Lecture Notes - Lecture 4: Big Five Personality Traits, Twin Study, Neuroticism
Document Summary
Example: on trait x, mz twins have a correlation of . 86 and dz twins have correlation of . 60. At this point, correlations are explained by both genetic & environmental factors we need to tease things apart. Key observation: sharing an additional half genome with your twin explain an additional 26 % of the variance. So, in theory, sharing a full genome explains 2 x 26% = 52% of the variance in x. Adoption studies: positive correlations between adopted children and genetic parents provide evidence of genetic influence. Major strength: genetic parents are providing no environmental influences (no confounding) *design that combines strength of twin and adoption studies: mz twins reared apart simply look at degree of concordance. Heritability estimates of personality: based on mz twins reared apart. Heritability estimates of big 5l based on mz & dz pairs.
