search for: zerinfl

Hello, I am working with zero inflated models for a current project and I am getting wildly different results from R's zeroinfl(y ~ x, dist="negbin") command and Stata's zinb command. Does anyone know why this may be? I find it odd considering that zeroinfl(y ~ x, dist="poisson") gives identical to output to Stata's zip function. Thanks, --david [[alternative

...imilar was log-likelihood (very close for all 3 models) and the number of predicted 0 (which was identical for each model), but what surprised me were the following results: -glm.nb identified as having an influence the same variables that were identified by the hurdle model in the zero-model; -zerinfl model identified also d variable as influential; Now my question is the following: having seen the vignette (Regression Models for Count Data in R) I noticed that glm.nb, hurdle and zeroinfl give similar results for the count model, while for the zero-component hurdle and zeroifl may give sli...