Hello, I just joined this list today, so am worried about proper protocol, but would like to post a question about lme4. In Baayen, Davidson, and Bates (2008), Mixed-effects modeling with crossed random effects for subjects and items, the authors describe steps for a Latin Square Design (p. 402) in which they compare 3 levels of the experimental conditions. I am considering replicating this analysis for my dissertation, I would also like to investigate 3 levels of my factor, but wish to confirm how lme4 derives the t value. It is my understanding that t values can only be used to compare 2 means. For 3 levels, does lme4 do some kind of pairwise comparison?
Henric (Nilsson) Winell
2012-Jul-27 21:31 UTC
[R] lme4 t value for 3 levels of fixed factor
On 2012-07-27 05:50, Obermeier Andrew wrote:> Hello, > > I just joined this list today, so am worried about proper protocol, but would like to post a question about lme4.The R-sig-mixed-models list (https://stat.ethz.ch/mailman/listinfo/r-sig-mixed-models) may be a better place for questions on lme4 and other packages fitting mixed effects models.> > In Baayen, Davidson, and Bates (2008), Mixed-effects modeling with crossed random effects for subjects and items, the authors describe steps for a Latin Square Design (p. 402) in which they compare 3 levels of the experimental conditions. I am considering replicating this analysis for my dissertation, I would also like to investigate 3 levels of my factor, but wish to confirm how lme4 derives the t value. > > It is my understanding that t values can only be used to compare 2 means. For 3 levels, does lme4 do some kind of pairwise comparison?For pairwise comparisons, and other contrasts, take a look at the 'multcomp' package. HTH, Henric> > ______________________________________________ > R-help at 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. >