Dear John I want to thank you so much for the help. I've solved my problem following your instructions. The matrix S of the cov was singular because i had few complete observation. I have included 2 wrongs item, because (in the majority of cases) when one is inputed, the other one is "NA", so i have only fews complete observations... Thank you so much again, for this help and for the great job about SEM( ) that you have wrote and shared on the web. My best regards, Costantino Milanese, always the young researcher but with less problems! [[alternative HTML version deleted]]
______________________________________________ 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.