Fig 4.jpg (173.38 kB)
Classical Twin Model
Version 2 2020-10-19, 20:10
Version 1 2020-08-01, 17:38
figure
posted on 2020-10-19, 20:10 authored by Sara HartSara Hart, Callie LittleCallie Little, Elsje van BergenElsje van BergenSimplified
representation of the classical twin model. In behavioral-genetic models the
three sources of influences on individual differences are commonly labeled by
the letters A, C, and E, respectively, stemming from Additive genetic influences (also known as heritability, and
sometimes represented by an h2 instead on an A), Common environmental influences (also
known as shared environmental influences), and non-shared Environmental influences (and measurement Error). Note that the latter are by definition uncorrelated between
twins. See for a detailed representation of the classical twin model for
example Figure A.9 in Knopik et al. (2017). rMZ = monozygotic twin
correlation; rDZ = dizygotic twin correlation.