topic Re: zero inflated negative binomial for a rate outcome in Statistical Procedures

zero inflated negative binomial for a rate outcome

LucyB — Tue, 14 Mar 2017 05:32:49 GMT

I have an outcome frequency over a variable number of years per patient. I have converted this to a rate per year and would like to investigate differences bet a certain category. The rates are overdispersed and zero inflated. How can I code a zero inflated negative binomial model in SAS for this rate outcome?

Re: zero inflated negative binomial for a rate outcome

Ksharp — Tue, 14 Mar 2017 06:01:25 GMT

PROC GENMOD

Re: zero inflated negative binomial for a rate outcome

LucyB — Tue, 14 Mar 2017 06:11:00 GMT

what about countreg?

e.g:

proc countreg data=data;
model rate = category covariate / dist=zinb method=qn;
zeromodel rate ~ category covariate;
run;

I was not sure how to model the zeromodel..

Re: zero inflated negative binomial for a rate outcome

Ksharp — Tue, 14 Mar 2017 09:42:31 GMT

I don't know PROC COUNTREG is under SAS/ETS, it is for time series.