Compute cov(beta) as a Function of varpar of an LMM
At the optimum cov(beta) is available as vcov(lmer-model). This function computes cov(beta) at non (RE)ML estimates of varpar
.
get_covbeta(varpar, devfun)
varpar
: variance parameters; varpar = c(theta, sigma)
.devfun
: deviance function as a function of theta only.cov(beta) at supplied varpar values.
Rune Haubo B. Christensen