摘要：This study relates negative binomial and generalized Poisson regression models through the meanvariance relationship, and suggests the application of these models for overdispersed or underdispersed count data. In addition, this study relates zero-inflated negative binomial and zero-inflated generalized Poisson regression models through the mean-variance relationship, and suggests the application of these zero-inflated models for zero-inflated and overdispersed count data. The negative binomial and generalized Poisson regression models were fitted to the Malaysian OD claim count data, whereas the zero-inflated negative binomial and zeroinflated generalized Poisson regression models were fitted to the German healthcare count data.
