follow-up (posthoc) analyses from an LMER model

2 messages · Antoine Tremblay, Tobias Verbeke

Wed, Oct 21, 2009 4:31 AM #

Hi everyone,
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).

Thanks for your time!

Antoine

Antoine Tremblay
Department of Neuroscience
Georgetown University
Washington DC

Tobias Verbeke

Wed, Oct 21, 2009 7:29 AM #

Hi Antoine,

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