A Simple and Adaptive Dispersion Regression Model for Count Data
Abstract
Regression for count data is widely performed by models such as Poisson, negative binomial (NB) and zero-inflated regression. A challenge often faced by practitioners is the selection of the right model to take into account dispersion, which typically occurs in count datasets. It is highly desirable to have a unified model that can automatically adapt to the underlying dispersion and that can be easily implemented in practice. In this paper, a discrete Weibull regression model is shown to be able to adapt in a simple way to different types of dispersions relative to Poisson regression: overdispersion, underdispersion and covariate-specific dispersion. Maximum likelihood can be used for efficient parameter estimation. The description of the model, parameter inference and model diagnostics is accompanied by simulated and real data analyses.
Cite
@article{arxiv.1511.00634,
title = {A Simple and Adaptive Dispersion Regression Model for Count Data},
author = {Hadeel S. Klakattawi and Veronica Vinciotti and Keming Yu},
journal= {arXiv preprint arXiv:1511.00634},
year = {2018}
}