Will like to know if you have an example in your achieves on how to test the invariance of class proportions, and class probabilities in LCA. Trying to test the gender invariance of class proportions and probabilities but cannot find a clear example to give me. Will appreciate if a clear example in your achieves is provided or any other link to help me.
When you have c ON cg in the model the class probabilities of c are free. When you do not have c ON cg in the model, the class probabilities of c are constrained to be equal across the cg classes. You can compare these two models.
I want to test the invariance across gender of my 3 class LPA model. I'm comparing the unconstrained model to a model having the means of my indicators constrained to equality in men and women using -2*LogLik difference (I also taking into account the scaling correction factors obtained with the MLR estimator, au you descibed in the web site).
1) This test is significant (suggesting non-invariance), but the BIC decreases (suggesting that the constrained model is better). Which I should trust the most?
2) Is the -2*Loglik difference test affected by sample size? (like DIFFTEST or Chi-square in measurement invariance). In my case I have 500 subjects in a dataset and 830 in a second one (I want to keep the 2 dataset separate).
3) Can I test partial invariance releasing some indicators from the equality constraint? Are there any statistical indices to "guide" this process (such as the modification indices in measurement invariance)?