Dear Anthony, >From ?sem:
"If given as NA, the program will compute a start value, by a slight modification of the method described by McDonald and Hartmann (1992). Note: In some circumstances, some start values are selected randomly; this might produce small differences in the parameter estimates when the program is rerun." To see exactly what's done, print out the startvalues function. Regards, John ------------------------------ John Fox, Professor Department of Sociology McMaster University Hamilton, Ontario, Canada web: socserv.mcmaster.ca/jfox > -----Original Message----- > From: [email protected] [mailto:[email protected]] On > Behalf Of Anthony Dick > Sent: January-25-09 9:15 PM > To: [email protected] > Subject: [R] sem package: start values > > Hello- > > If I input a variance-covariance matrix and specify NA for start values, > how does sem determine the start value? Is there a default? > > Anthony > > -- > Anthony Steven Dick, Ph.D. > Post-Doctoral Fellow > Human Neuroscience Laboratory > Department of Neurology > The University of Chicago > 5841 S. Maryland Ave. MC-2030 > Chicago, IL 60637 > Phone: (773)-834-7770 > Email: [email protected] > Web: http://home.uchicago.edu/~adick/ > > ______________________________________________ > [email protected] 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. ______________________________________________ [email protected] 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.
