On 3 April 2011 12:38, jouba <antr...@hotmail.com> wrote: > > Daer all, > I have a question concerning longitudinal data: > When we have a longitudinal data and we have to do sem analysis there is in > the package lavaan some functions,options in this package that help to do > this or we can treat these data like non longitudinal data >
No, and (qualified) no. 1. There are (AFAIK) no options, functions that are specific to longitudinal data. 2. You don't treat these data as non-longitudinal data, you add parameters that are appropriate though. For example, look at the model shown on http://lavaan.ugent.be. dem60 and dem65 are two measures of the same construct at different timepoints, so there are correlations over time for each pair of measured variables that are measures of that construct - i.e. y1 ~~ y5 3. You would get much better answers on the SEM mailing list - semnet. You can join it here: http://www2.gsu.edu/~mkteer/semnet.html#Joining. Jeremy -- Jeremy Miles Psychology Research Methods Wiki: www.researchmethodsinpsychology.com ______________________________________________ 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.
