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> ## drop1 may not work right with contrasts: make up an example something like this ...
> ## options(contrasts=c("contr.sum","contr.poly"))
> ## drop1(fecpoiss_lm3,test="Chisq",scope=.~.)
> 
> 
> if (.Platform$OS.type != "windows") withAutoprint({
+     library(lme4)
+     oldopts <- options(contrasts=c("contr.sum","contr.poly"))
+     fm1 <- lmer(Reaction~Days+(Days|Subject),data=sleepstudy)
+     drop1(fm1,test="Chisq")
+     ## debug(lme4:::drop1.merMod)
+     drop1(fm1,test="Chisq",scope=.~.)
+ 
+     fm0 <- lm(Reaction~Days+Subject,data=sleepstudy)
+     drop1(fm0,test="Chisq",scope=.~.)
+     options(oldopts)  ## restore original contrasts
+ 
+     ff <- function() {
+         lmer(Reaction~Days+(Days|Subject),data=sleepstudy)
+     }
+     drop1(ff())  ## OK because sleepstudy is accessible!
+ 
+ }) ## skip on windows (for speed)
> 
> proc.time()
   user  system elapsed 
   0.20    0.01    0.20