That is, the variance of Y is , where >1. With overdispersion, methods based on quasi-likelihood can be used to estimate the parameters and .A quasi-likelihood function is specified by its associated ...

Generalized variance functions (GVF's) are used in a number of sample surveys as a convenient method of publishing sampling errors. The method consists of estimating the relative variance (relvariance ...

Jianqing Fan, Qiwei Yao, Efficient Estimation of Conditional Variance Functions in Stochastic Regression, Biometrika, Vol. 85, No. 3 (Sep., 1998), pp. 645-660 ...