Hi, I am running some latent class models with civariates using poLCA in R, and have a question the meaning of some error messages.
My model has 8 y-variables (dichotomous) and 2 x-variables (also dichotomous), and I am trialling different numbers of classes. When I run a 2-class model, the model runs fine without any error messages. I used the nrep = 10 option to avoid local maxima. Class % are ~81% and 19%. When I trial a 3-class model, firstly I upped the nrep to 200, since for some runs it isn't till run 139 that the maximum is found. Class % are ~81%, 16% and 2%. These vary a LOT if a model based on a local maximum is used. Anyway, for the final model with max, I get the following message: Warning messages: 1: In sqrt(diag(VCE.beta)) : NaNs produced 2: In sqrt(diag(VCE.beta)) : NaNs produced 3: In sqrt(diag(VCE.mix)) : NaNs produced 4: In sqrt(diag(VCE.beta)) : NaNs produced 5: In sqrt(diag(VCE.mix)) : NaNs produced What does this mean for the model? Cheers, Lucy ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
