st: zero-inflated poisson or negative binomial regression for panel data?

[Jason Yackee <jyackee@law.usc.edu>]

Dear all,

I am estimating panel models of count data using negative binomial and
Poisson regression (-xtnbreg- and -xtpoisson-).  My zero counts appear
to be "inflated", and I would like to use a zero-inflated Poisson
approach, such as that available in Stata as the -zip- routine.  Is
there a way to adapt this for use with panel data?  Is there some other
way to deal with excess zeros in a panel count-data setting?

Any help very much appreciated.

Jason Webb Yackee, PhD Candidate; J.D.
Fellow, Gould School of Law
University of Southern California
jyackee@law.usc.edu
Cell: 919-358-3040

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