Anonymous posted on Thursday, July 12, 2012 - 3:56 am
I am hoping someone can advise me how to merge latent classes in Mplus. For example, I have a situation with 4 classes, with probabilities of class membership as 40%, 30%, 25%, and 5%. For the purposes of estimating predictors of class membership, I wish to amalgamate the third and fourth classes so that the first two classes are unaffected. What syntax would I use in Mplus? Would I use the training option and if so would the membership or probabilities sub-option be most appropriate?
Anonymous posted on Thursday, July 12, 2012 - 1:36 pm
Thanks for that response. My reason for asking was I have seen some multiple group latent class analyses in the literature where, when a model was fitted and some classes in certain groups had 0 (or very close to 0) probability of class membership, the model was refitted forcing membership in these classes to be 0, on the argument this improves model fit. I was interested in learning how to do this, or your opinion on this approach. Thank you.
If you want one less class, run the model with one less class. If the classes don't combine the way you would have forced, it may not be wise to force the two classes together. That does not reflect what the data says.