The evidence here to me implies that you are just trying to fit a model

that can't be fit to your data. With panel data any number of things

could be problematic.

Bear in mind that what to you is a problem -- Stata has "stopped

working" -- is to Stata a problem in that you asked an unanswerable

question.

This falls a long way short of a bug report that anyone could

investigate. Showing that the same data and the same model could be

fitted satisfactorily in other software would be an example of a

situation where StataCorp would want to see the details.

Nick

[hidden email]
Narasimhan Sowmyanarayanan

I am working on some data in which the dependent variable is a count

number. The data is over-dispersed. So I am trying to work with xtgee.

xtgee [depvar] [independent var] , family(nbinom) link(log)

corr(exchangeable) exposure(year)

I keep getting the error that says:

estimates diverging (missing predictions)

r(430);

I am using Stata 10.1. I noticed in one of the postings on the stata

website that this was a bug in stata 9 that has been fixed ? I also

tried to look at old postings on the stata listserv to see if any

solutions suggested there helps. None of them help me. Can someone

tell me what the problem can be and how I can solve this. Any insights

will be highly appreciated.

In particular, this happens if I add some non-linear terms and

interaction terms in the model. It does not converge. I tried building

the model one variable at a time. i can see that the moment I add the

non-linear xtgee stops working. I have used the same model in other

contexts too with non-linear terms such as OLS regression xtreg

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