Logistic Regression Using SAS®: Theory and Application

10.1. Introduction

In Chapter 4, we saw how to analyze contingency tables that included a dichotomous variable treated as dependent on the other variables. The strategy was to directly estimate a logit model in PROC LOGISTIC or PROC GENMOD. We extended that approach in Chapter 5 to handle dependent variables with more than two categories by estimating a multinomial logit model with PROC CATMOD. In this chapter, we see how to estimate loglinear models for contingency tables. What distinguishes loglinear models from logit models is that loglinear models do not have an explicit dependent variable, at least not one that corresponds to any conceptual variable. As I’ve mentioned previously, every logit model for a contingency table has a loglinear ...