Figure 2.

A summary of our structural equation model. (A) A traditionally drawn pedigree of a nuclear family, with two parents (father: F and mother: M) and two children (sister: S and brother: B). As per convention, squares represent males and circles represent females. (B) The pathway diagram for our structural equation model’s description of the phenotypic correlation between the two siblings from the family depicted in (A). Please note the different convention for node shapes in pathway diagrams for structural equation models: here, squares represent observable states (phenotypes), while circles represent latent states. See Supplemental Text, section 1 for more discussion of these diagrams and a full explanation of the model.