Extract variance covariance matrix from objects of class geeglm
Only for internal use with function glht: Extract the variance covariance matrix corresponding to the mu parameters of a gamlss-fit. Merely a wrapper of the method internally used in function summary.geeglm, package geepack.
An object of class "geeglm" as can be created by calling
Currently not used.
Test version. Only for internal use. Needs implementation of warnings.
A matrix of dimension m times m, if m is the length of coefficients from a geeglm fit.