Thread: Binary Logistic Regression with Categorical Dependents /AIC Model Selection

I am wanting to investigate the relationship between bear-human conflicts and a number of continuous variables (ex. aspect, slope, solar radiation, etc.) by using true conflicts and pseudo conflicts (created by generating random points from true points) as my dependent variable. I was wanting to use PROC REG, but from what I understand this is limited to non-categorical dependent variables. I just recently tested out CATMOD, but I am not sure...

Go to support.sas.com and search for catmod aic and you will find a paper that should answer your question.

If your response is binary, you can fit a logistic model using PROC LOGISTIC or PROC GENMOD. Neither does model selection based on AIC. However, both display the AIC for any single model that you fit (in GENMOD, AIC is displayed beginning in SAS 9.2). You can do model selection based on p-values using the SELECTION= option in PROC LOGISTIC. See also the SLENTRY= and SLSTAY= options, all in the MODEL statement.

You can use PROC GLMSELECT for the model selection, and then use the model that it selects in PROC LOGISTIC or PROC GENMOD. Although GLMSELECT is designed for model selection for GLM, it works well with logistic models too. See my paper (coauthored with David Cassell) at NESUG last year .... www.nesug.org/Proceedings/nesug09/sa/sa01.pdf although I recomend LASSO or LAR rather than AIC, this PROC can use AIC selection Peter