Random slopes for categorical variables
Yes. Well, to be more precise 0 + CAT and 1 + CAT estimate different contrasts and so the correlation you're estimating correspond to whatever contrast comes out. Same deal for 1 + CAT with sum vs treatment vs. Helmert coding.
On 5/10/21 10:20 pm, Timothy MacKenzie wrote:
Hello All, I had a basic question. For continuous variables (X) killing the intercept in the random part kills the correlation between random effects (intercepts and slopes): (0 + X | ID) But for categorical variables (CAT) killing the intercept actually allows for all levels of CAT (including the reference level) to be correlated that is: (0 + CAT | ID) estimates more correlations than (CAT | ID) Am I correct? Thanks, Tim M
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