Hi, I have a fairly simple repeated measures-type data set I've been attempting to analyze using the lme function in the nlme package. Repeated searches here and other places lead me to believe I have specified my model correctly.
However, I am having trouble with post-hoc tests. From what I gather, other people are successfully using the glht function from the multcomp package to perform post-hoc tests. I've tried multiple iterations, but can't seem to get it to work. Here is (a subset of) what I have been trying. Any help would be greatly appreciated: > model.3<-lme(fixed=Totnum~Wk*Pop, random=~1|nUID, data=nona) #Wk has 6 levels, 0-5; Pop has 2 levels; nUID is a unique ID given to each individual (multiple individuals from each population were re-measured each week) > anova(model.3) numDF denDF F-value p-value (Intercept) 1 592 649.7753 <.0001 Week 5 592 302.9706 <.0001 Pop 1 222 70.7268 <.0001 Week:Pop 5 592 36.8576 <.0001 > summary(glht(model.3, linfct=mcp(Wk = "Tukey"))) Error in mcp2matrix(model, linfct = linfct) : Variable(s) ‘Wk’ of class ‘integer’ is/are not contained as a factor in ‘model’. > is.factor(Wk) [1] FALSE > Week<-factor(Wk) > is.factor(Week) [1] TRUE > model.3<-lme(fixed=Totnum~Week*Pop, random=~1|nUID) > summary(glht(model.3, linfct=mcp(Week = "Tukey"))) Error in contrMat(table(mf[[nm]]), type = types[pm]) : less than two groups Thanks, Rob -- View this message in context: http://r.789695.n4.nabble.com/post-hoc-test-for-lme-using-glht-tp2297882p2297882.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.