internal function for sandwich estimator
updateSandW(y, x, vfun, mu, w, D, Ralpha, beta, hessmat, blockdiag)response value for GEE model
model matrix for the GEE model
variance function for the GLM
mu vector for the GLM
weight matrix
derivation of the inverse link function
correlation matrix
vector of beta value for GEE model
hessian matrix
vector containing the dim of block matrix for block diagonal matrix
arguments are required for obtaining Sandwich Estimator for variance matrix of regression coefficient of GEE model