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Re: st: which -cmp- option to use for poisson model with count data?


From   Richard Williams <[email protected]>
To   [email protected], [email protected]
Subject   Re: st: which -cmp- option to use for poisson model with count data?
Date   Tue, 01 May 2012 09:01:14 -0500

At 05:51 AM 5/1/2012, Maarten Buis wrote:
On Tue, May 1, 2012 at 12:16 PM, Laura R. wrote:
> If I understand you correctly, by default 0 is treated as missing in
> -poisson- (not so in -oprobit-, I think)?

That is incorrect. In -poisson- 0 is treated as 0, so do _not_ change
you dependent variable.

As a sidelight, people are used to thinking they can add or subtract constants from variables or otherwise rescale them, and that it won't matter. Do NOT do that with the dependent variable in a count model.


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Richard Williams, Notre Dame Dept of Sociology
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