# Diagnostic plots for lmer

I am trying to produce a glmm using the lme4 package in R. To validate my model I would like to produce some diagnostic plots but am having trouble doing so as many of the packages that work for lm() models like CAR do not work for lmer() models. I have tried using the languageR and asuR packages but am just getting errors. I am particularly interested in creating partial residual plots.

I have been able to produce qqplots, residual vs fitted plots and look at cooks distances manually. Any suggestions of further plots I should try or packages that would help would be greatly appreciated.

fm <- lmer(Average.payoff ~ Game + Type + Others.Type + Game*Type + Game*Others.Type +
Type*Others.Type + (1|Subjects), REML=FALSE, data=Subjectsm1)

library(asuR)
inspect(fm)
Error in .setupMethodsTables(fdef, initialize = TRUE) :
no slot of name "group" for this object of class "derivedDefaultMethod"

library(languageR)
plotLMER.fnc(fm)
warning: I don't know how to handle  Game
Error in preparePredictor.fnc(predictors[i], model, m, ylabel, fun, val = NA,  :