Hi, all, dear SAS community,
Please bear with me if I returned with too simple a stats question.
I ran two Poisson models, one simply with controls, the other with controls plus variables of interest.
/** Model (1) **/
proc genmod data = dataset;
model Y = X1 X2 X3 X4 X5 year1-year9 ind1-ind63 / dist=poisson link=log; run;
/** Model (2) **/
proc genmod data = dataset;
model Y = X1 X2 X3 X4 X5 X6 X7 X8 X9 X10 year1-year9 ind1-ind63 / dist=poisson link=log; run;
I want to check whether one model is more significant (in terms of fit) than the other. In other words, I want to perform a model test like F-Test when comparing OLS models. According to my internet search, Poisson works differently; they suggest using CONTRAST option in PROC GENMOD but I am not really sure. And the ways they show how to use CONTRAST options look so complicated. Please help! I really appreciate you, SAS community!
Sincerely,
KS -,
Indeed, you need a a likelihood ratio test.
Like is said on this page:
SAS® 9.4 and SAS® Viya® 3.5 Programming Documentation
SAS Visual Statistics Programming Guide
Regression Action Set
Poisson Regression
https://go.documentation.sas.com/doc/en/pgmsascdc/9.4_3.5/casactstat/casactstat_regression_examples0...
Koen
See this note and the examples it links to.
Indeed, you need a a likelihood ratio test.
Like is said on this page:
SAS® 9.4 and SAS® Viya® 3.5 Programming Documentation
SAS Visual Statistics Programming Guide
Regression Action Set
Poisson Regression
https://go.documentation.sas.com/doc/en/pgmsascdc/9.4_3.5/casactstat/casactstat_regression_examples0...
Koen
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