follow-up (posthoc) analyses from an LMER model
Hi Antoine,
I'm wondering how to do follow-ups for an LMER model (e.g., Y ~ A * B + (1|Subject) + (1|Item) ) If you fit a model using the function aov(), naturally without the random effects terms, you can use the TukeyHDS() function to do multiple comparisons or the pairwise.t.test() function. Unfortunately, these two functions can't be used to do posthocs analyses from an LMER model (at least to the extent of my knowledge).
Have a look at the multcomp package. It knows how to deal with lmer objects (and has lmer examples in the package vignettes). http://cran.r-project.org/web/packages/multcomp/index.html HTH, Tobias