Hi, and thanks for the advices. I actually tried using 'lme', but haven't figured out the appropriate syntax to get the random error correct with repeated measures. let's say i have 3 independent variables, with 'aov', i would write something like: aov(dep_var~(indep_var1*indep_var2*indep_var3) + Error(subject/(indep_var1*indep_var2*indep_var3)).
With 'lme' however, i can't find the right formula. i tried things like: lme(dep_var~(indep_var1*indep_var2*indep_var3), random = ~1|subject) or nesting my independent variables in 'subject', but those are obviously wrong with my design. i'm quite clueless (and i haven't found any convincing piece of information about how to correctly use 'lme' or 'lmer'). So, any advice along that line is more than welcome. JP Frank E Harrell Jr wrote: > > Dieter Menne wrote: >> Jean-Pierre Bresciani <bresciani <at> tuebingen.mpg.de> writes: >> >>> is there a specific/appropriate function/package to perform post hoc >>> tests >>> when running a two way repeated measures anova? I'm looking for >>> something >>> that will be equivalent to the 'TukeyHSD()' for between subjects anova >>> (with >>> 'aov()'). For one way repeated measures anova, the 'pairwise.t.test()' >>> function seems to work correctly but the results are questionable for >>> two+ >>> way anovas, as if the adjustment of the p values for multiple >>> comparisons >>> was not correct. >> >> Classical repeated measurement has fallen a bit out of favor, because >> mixed >> models as in lme (package nlme) and lmer(package lme4) are MUCH more >> flexible >> and in general more stable when data are missing. > > And don't forget generalized least squares (gls in nlme) which has the > same advantages using only fixed effects. > > Frank > >> >> So I recommend to switch to lme (better documented, currently), and use >> >> http://finzi.psych.upenn.edu/R/Rhelp02a/archive/20725.html >> >> as a starter when trying to do multiple comparisons. >> >> Dieter Menne (Tübingen) >> > > -- > Frank E Harrell Jr Professor and Chair School of Medicine > Department of Biostatistics Vanderbilt University > > ______________________________________________ > 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/post-hoc-tests-two-way-repeated-measures-anova-tp18999089p19031169.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.
