Hallo
I have a problem concerning the reference category of categorical variables.
Normally I take a low reference category to fit the model. I observed that the intercept changes in function of the reference category I putted to the model. I also observed that if I take the lowest reference category, I get an error message that the matrix has gone negative. But if I take the middle category of the same variable, the model calculates without any problem.
Could anyone explain me why this happens?
Best regards, Jeannine
Intercept changes when defining diff. reference categories
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Re: Intercept changes when defining diff. reference categories
See my reply to your post in the topic http://www.cmm.bristol.ac.uk/forum/view ... ef9e6e36af- think that will answer this question too!