Figure 2.

Partial path diagram for the Children-of-Twins structural equation model

^a A1=additive genetic effects on parent trait; A2=additive genetic effects specific to adolescent trait; A1′=additive genetic effects common to parent and adolescent traits (path from A1 to A1′ is fixed to .50 because offspring inherit 50% of their parent’s genes); p=residual non-genetic association between parent and adolescent traits; C1/C2=shared environment effects on parent/adolescent trait; E1/E2=nonshared environmental effects on parent/adolescent trait. Variance=1 for all latent factors.