I am modelling logistic regressions in SPSS, the same model for different countries (well, with slight differences in the independent variables set due to collinearity diagnosis and stepwise results). The model seems to work fine for most countries. In two countries, I am having some issues with the same variable. The variable has three categories (hierarchical). In the output for those two beautiful countries, seems that SPSS take the reference category out, assumes other as reference category and gives exp(B) for the last category.
Is there something wrong going on? What should / can I do about it?
Thanks a lot for your answers! The problem cannot be in the syntax since I am using the same for all countries and works perfectly.
I am using ENTER. The STEPWISE was used as an exploratory method to identify the strongest predictors. According to the -2LL values my variable is not a 'strong' one for this two countries (0.12%). Is not the first time that I read that STEPWISE is a bad choice... I will that in account!
Nevertheless, why do SPSS does that? Is this a real problem, meaning something that I must solve? Or can I use/report the odds for those two countries without that category adding a footnote? Should I run the model without that variable (theorectically the variable is not that important).
Hi, All my variables are recoded to the reference category be 1 and most of my variables have three categories. I am using Enter with the following syntax. LOGISTIC REGRESSION VAR= "DV" /METHOD=ENTER "IV's" /CONTRAST ("IV")=Indicator (1) [...] /PRINT=GOODFIT CI(95) /CRITERIA PIN(.05) POUT(.10) ITERATE(20) CUT(.5). Do you have idea what is going wrong?