Jenny Walter posted on Wednesday, December 27, 2017 - 6:30 pm
I have not seen examples of it, but are there any identification issues with a latent difference mixture model?. I know how to do a latent difference score (LDS) model and latent class/profile analyses, but when I mix on the LDS, I get errors. Specifically, it states: THE LATENT VARIABLE COVARIANCE MATRIX (PSI) IN CLASS 2 IS NOT POSITIVE DEFINITE. THIS COULD INDICATE A NEGATIVE VARIANCE/RESIDUAL VARIANCE FOR A LATENT VARIABLE, A CORRELATION GREATER OR EQUAL TO ONE BETWEEN TWO LATENT VARIABLES, OR A LINEAR DEPENDENCY AMONG MORE THAN TWO LATENT VARIABLES.