st: zip vs. Hurdle

[Johanna LEPEULE <lepeule@vet-nantes.fr>]

Hi

I use a zip model and the parameters estimated by zip predict a low 
probability of observations being a Poisson zero. Thus, it seems to me that 
a Hurdle regression model could be more adapted with a logistic part to 
predict zero and a Poisson part for nonzero.
However, I think that the results will be not very different between the 
zip and the Hurdle regression model.

To your opinion, Is it true ?

Thanks
Johanna Lepeule


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