Hi. I'm starting to do a poisson regression with proc genmod and wanted to first check that I have my data summarized correctly. I assumed that I could test this with the following crude model without covariates and compare the estimate with a by-hand calculation of outcome/person-time.
proc genmod data=summarized;
MODEL outcome= /dist=poisson link=log offset=logdenomcount;
estimate "Crude" intercept 1;
run;
However, the estimate and my by-hand rate are not the same. Is my assumption these should match incorrect?
Ah, I just went back and realized I made my offset off of the _Freq_ when I did my proc summary and not the summed denominator count. Therefore my numbers were off.
Correcting that now produces a match with my by-hand calculation as I thought should be the case.
Ah, I just went back and realized I made my offset off of the _Freq_ when I did my proc summary and not the summed denominator count. Therefore my numbers were off.
Correcting that now produces a match with my by-hand calculation as I thought should be the case.
If you want to get RATE ,check "Mean Estimate" column .
If you want to get COUNT, check "L'Beta Estimate" column.
It's finally time to hack! Remember to visit the SAS Hacker's Hub regularly for news and updates.
ANOVA, or Analysis Of Variance, is used to compare the averages or means of two or more populations to better understand how they differ. Watch this tutorial for more.
Find more tutorials on the SAS Users YouTube channel.