Stata The Stata listserver
[Date Prev][Date Next][Thread Prev][Thread Next][Date index][Thread index]

st: poisson fixed effects


From   [email protected]
To   [email protected]
Subject   st: poisson fixed effects
Date   Thu, 15 May 2003 08:56:17 -0400

Hi all,
I have a question:
I tired to use a fixed effect poisson estimation (xtpois...,fe). As well 
known, the undelying conditional likelihood is actually conditional on the sum 
of the outcomes, and this gives something that recall a multinomial logit, 
such that the individual specific effect gets canceled out. Since this is a 
non linear model, this is different from the "within" estimator in a linear 
fixed effect model, which, in turn, is equivalent to adding a set of dummies.

Now, I tried to estimate a model with xtpois...,fe and, after that, I 
estimated it with the simple poisson command and added dummies for my cross 
sectional unit. Now, I get the same results. This is clear for a linear model, 
but, should I be surprised or not that I got it in poisson?

Thanks,
nico

*
*   For searches and help try:
*   http://www.stata.com/support/faqs/res/findit.html
*   http://www.stata.com/support/statalist/faq
*   http://www.ats.ucla.edu/stat/stata/



© Copyright 1996–2024 StataCorp LLC   |   Terms of use   |   Privacy   |   Contact us   |   What's new   |   Site index