On Tue, 4 Mar 2003 10:14:06 -0800, <[email protected]> wrote: > Hi, Pat.
Hi, Steve. > WRT to (b), I would also consult the efficiency index described by Rubin > (1987) and discussed by Schafer in the Norm help file > under "How many imputations do I need?". I believe the efficiency is > output by Norm (but strangely not output by SAS PROC MIANALYZE, though it > can easily be computed from the information provided). Yes, thanks. That one's puzzled me: If I'm applying it correctly, it seems to asymptote at fairly high levels even with very high degrees of missing information. > In many longitudinal data sets I have found that 10 imputed data sets did > not result in sufficient efficiency. I typically go with 20 imputed data > sets. > > Steve Thanks. My colleague is going back over the missing information levels as we speak. Pat -- Patrick S. Malone, Ph.D., Research Scholar Duke University Center for Child and Family Policy Durham, North Carolina, USA e-mail: [email protected] http://www.duke.edu/~malone/
