Hi everyone, I am trying to fit a GAM model with Poisson rates data which include an offset term. I have tried using this code: proc gam data=mydata; model dv=spline(x1) spline(x2) splineline(x3) / dist=poisson link=log offset=lexp anodev=norefit; output out=mydout p; run; For some reason the offset term is indicated as an error in the log file. I am not sure how can I indicate I am dealing with rates not with counts. If I do not specify an offset term, the smoothing is being done for the count data, right? I also have a question about testing the linearity of the association - is this a sound procedure? 1. I wanted to test each of the independent variables to see if they display a linear or quadratic association with my dependent variable - that is why I tried using GAM. 2. In case GAM indicates only significant linear tends for all my predictors except for one, can I still use then proc genmod with an offset (which I ran; it worked just fine, assuming a linear association, no weird coefficients). I was also considering using the proc adaptvereg, not sure that is a better option in my case. Thank you very much for taking the time to read my post and to help me! Best regards1
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