Re: st: checking over dispersion in XTPOISSON

[Eric N <eric.erictor@gmail.com>]

One of the problems with Poisson is that the variance is assumed to
equal the mean which is a very restriction condition.   You might wish
to try the negative binomial that also is used to analyze count data
and is less restrictive in this regard.

--Eric

On 1/5/12, Rajaram Subramanian Potty <rajara999@gmail.com> wrote:
> Dear all,
>
> I would like to know how one should check for overdispersion in a
> model fitted using "xtpoisson". If one noticed overdispersion how to
> correct it or which is the alternative analysis.
>
> Thanks in advance.
>
>
> RAJARAM
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