st: poisson regression predicted values

[Richard Goldstein <richgold@ix.netcom.com>]

Dear listers:

I have estimated a poisson regression (includes some interaction terms and 
uses cluster SE's).  After estimation I obtained predicted values (-predict 
newvar, ir-) and some of the IR's are greater than 1.0 (Similarly, using 
-predict newvar- gives some counts that are greater than the exposure (or 
denominator).)  I have not known this to occur before and have the following 
questions:

1. is this a serious problem?

2. (esp. if answer to 1 is "yes") -- what might cause this and, therefor, what 
can I do about it?

Thanks,

Rich Goldstein

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