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How do I read the parameter codings of categorical variables in SPSS?

Question & Answer


Question

I am running SPSS binary logistic regression or Cox regression with a categorical covariate. When I run the model with the default contrast specification of Indicator(last), I get parameters identified with numbers (1), (2), etc., up to one less than the number of categories of the predictor. However, when I change the reference category to first, I get the same labeling. Is the procedure internally recoding the levels of the variable? I'm not sure how to interpret the output.

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Historical Number

72755

Document Information

Modified date:
16 April 2020

UID

swg21478246