Falconer's formula for broad sense heritability is 2*(r_monozygotic - r_dizygotic).
Mayhew and Meyer (2017) states: "Subtracting the DZ phenotypic correlation from the MZ phenotypic correlation provides an estimate of the variance contributed by genetics when 50% of DNA is shared."
If we are seeking an estimate of the additional variance explained by an additional 50% of shared genes, shouldn't we be subtracting r^2 values rather than r values because r^2 is the proportion of variance explained?
