Computes the generalized heritability of a random-effect term from a fitted linear mixed model. By default, a single scalar heritability value is returned. Optionally, a spectral decomposition is provided that reveals how genetic signal is distributed across estimable genetic directions.
getHeritability(obj, geno.term, type = c("scalar", "spectral"), tol = 1e-08)If type = "scalar", a numeric value giving the generalized heritability.
If type = "spectral", a data frame with columns:
Index of the spectral component
Canonical heritability for the component
Weight of the component (genetic capacity)
Contribution of the component to total heritability
In the spectral case, the scalar generalized heritability is also available as
the attribute "h2_G".
An object of class "LMMsolve".
A character string giving the name of the genetic random-effect term.
Character string specifying the output:
"scalar" (default) returns a single numeric heritability value;
"spectral" returns a data frame with the spectral decomposition.
Numerical tolerance used to determine the estimable genetic space.
Generalized heritability is defined as the proportion of estimable genetic signal retained by the design relative to the available genetic capacity, accounting for the genetic covariance structure.
For independent genotypes, this definition reduces to classical generalized heritability measures based on effective dimension (Cullis, Oakey, Rodríguez-Álvarez). When genotypes are correlated, the spectral decomposition reveals anisotropy in information retention across genetic directions.