Praise for the Second Edition:"… this is a useful, comprehensive compendium of almost
every possible sample size formula. The strong organization and carefully defined formulae …

In many biometrical applications, the count data encountered often contain extra zeros
relative to the Poisson distribution. Zero‐inflated Poisson regression models are useful for …

Five regression models (Poisson, negative binomial, quasi-Poisson, the hurdle model and
the zero-inflated Poisson) were used to assess the relationship between the abundance of a …

Categorical data arise often in many fields, including biometrics, economics, management,
manufacturing, marketing, psychology, and sociology. This book provides an introduction to …

The Vuong test for non-nested models is being widely used as a test of zero-inflation. We
show that such use is erroneous. We see that this stems from a misunderstanding of what is …

Count data with excess zeros relative to a Poisson distribution are common in many
biomedical applications. A popular approach to the analysis of such data is to use a zero …

Health services data often contain a high proportion of zeros. In studies examining patient
hospitalization rates, for instance, many patients will have no hospitalizations, resulting in a …

In many situations count data have a large proportion of zeros and the zero-inflated Poisson
regression (ZIP) model may be appropriate. A simple score test for zero-inflation, comparing …

This study examines the incidence of sudden infant death syndrome (SIDS) in Canterbury
(1973–1989) in relation to climate. Three mixture models (Finite Mixture, Zero-inflated …

Rationale: Asthma prevalence and morbidity are especially elevated in adolescents, yet few
interventions target this population. Objectives: To test the efficacy of Asthma Self …