Peter Flom wrote: >> I am puzzled by the performance of LME in situations where there are >> missing data. As I >> understand it, one of the strengths of this sort of model is how well it >> deals with missing >> data, yet lme requires nonmissing data.
You are confusing missing data with an unbalanced design. A strengths of LME is that it copes with the latter, which aov() does not. Regards, Mark. Peter Flom-2 wrote: > > Hello > > Running R2.9.2 on Windows XP > > I am puzzled by the performance of LME in situations where there are > missing data. As I understand it, one of the strengths of this sort of > model is how well it deals with missing data, yet lme requires nonmissing > data. > > Thus, > > m1.mod1 <- lme(fixed = math_1 ~ I(year-2007.5)*TFC_, > data = long, > random = ~I(year-2007.5)|schoolnum) > > causes an error in na.fail.default, but adding na.action = "na.omit" makes > a model with no errors. However, if I create that model, i.e. > > m1.mod1 <- lme(fixed = math_1 ~ I(year-2007.5)*TFC_, > data = long, > random = ~I(year-2007.5)|schoolnum, > na.action = "na.omit") > > then the diagnostic plots suggested in Pinheiro & Bates produce errors; > e.g. > > plot(m1.mod1, schoolnum~resid(.), abline = 0) > > gives an error "could not find function "NaAct". > > > Searching the archives showed a similar question from 2007, but did not > show any responses. > > Thanks for any help > > Peter > > ) > > Peter L. Flom, PhD > Statistical Consultant > Website: www DOT peterflomconsulting DOT com > Writing; http://www.associatedcontent.com/user/582880/peter_flom.html > Twitter: @peterflom > > ______________________________________________ > 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. > > -- View this message in context: http://www.nabble.com/Missing-data-and-LME-models-and-diagnostic-plots-tp25996584p25998546.html Sent from the R help mailing list archive at Nabble.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.
