Hallo, I run a multilevel MCFA. The data is from a diary study, and the same variable was measured in the morning, and 2 hours later (3 other variables were measured at the second time point). I have 5 factors, but two of them referring to the same items, just different time points. I keep on getting the "not positive theta matrix" warning, although I have no negative residual variances, or correlations equal or greater than 1. I was wondering what / how could I proceed. Thank you very much in advance.
WARNING: THE RESIDUAL COVARIANCE MATRIX (THETA) IS NOT POSITIVE DEFINITE. THIS COULD INDICATE A NEGATIVE VARIANCE/RESIDUAL VARIANCE FOR AN OBSERVED VARIABLE, A CORRELATION GREATER OR EQUAL TO ONE BETWEEN TWO OBSERVED VARIABLES, OR A LINEAR DEPENDENCY AMONG MORE THAN TWO OBSERVED VARIABLES. CHECK THE RESULTS SECTION FOR MORE INFORMATION.