Re: st: Predicted probabilities after Poisson regression

[Maarten buis <maartenbuis@yahoo.co.uk>]

--- On Tue, 6/7/10, Gillian.Frost@hsl.gov.uk wrote:
> Looking at the help file for Poisson postestimation, there
> is an option -pr(n)- or -pr(a,b)- for -predict-, which
> calculates unconditional  probabilities.  However, when I
> look in the manual for more information there is no mention
> of this option.
> 
> I was hoping that someone would be able to help me find out
> more  information about how predicted probabilities are
> estimated after Poisson  regression.

As Martin mentioned these are new options in Stata 11.1, which
is probably why they aren't in the pdf manuals yet (this is
certainly the reason why they aren't in the paper manuals).

However, you can see the function that lead to these 
probabilities on page 1372, the methods and formulas section
of -poisson-, it is a pretty straightforward transformation
of the linear predictor.

Hope this helps,
Maarten

--------------------------
Maarten L. Buis
Institut fuer Soziologie
Universitaet Tuebingen
Wilhelmstrasse 36
72074 Tuebingen
Germany

http://www.maartenbuis.nl
--------------------------


      

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