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Re: st: Poisson regression

From   "Svend Juul" <[email protected]>
To   <[email protected]>
Subject   Re: st: Poisson regression
Date   Sun, 31 Jul 2005 21:35:40 +0200

Azi wrote:

I am looking at the predictors of standardised mortality

ratio (SMR) for my cohort. I have two datasets:

-the first one contains death; person-years of observation

and different variable which i want to check as predictors

of smr.

-the second dataset contains the rate of mortality 

(adjusted for sex and age) for the reference population.


After stset and stsplit in the first dataset, i merged it

with the second one and calculated the expected number of

death (e) for my cohort. In order to look at the 

predictors of smr i used the following syntax:


xi: poisson _d  i.psy  i.cob ......., exposure(e) irr. 


I wonder whether the selection of "e" as the exposure is 

correct when my dependent variable is smr?


When i fit different models, pseudo R^2 is very small 

(around 0.02) in all of them. This happens even when I 

include variables which influence smr. For all models use of

poisgof gives a good results.



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