[R] R lmer debugging: Error in [[<-.data.frame(*tmp*, i, value = integer(0)) : replacement has 0 rows, data has 117

[Ben Bolker]

Cynthia Tedore <Cynthia.Tedore <at> biol.lu.se> writes:

> 
> males is a factor. If I don't specify that, then it
> treats it as a numeric.
> any other suggestions?

transform(spiders,focal.chel=as.numeric(focal.chel),
        opponent.chel=as.numeric(opponent.chel),fmales=factor(males))

model1<-lmer(threatened~focal.chelopponent.chel+(1|fmales),
   na.action=na.omit,data=spiders)

  I'm quite surprised (and a little skeptical) that `lmer` treats
males as a numeric in that particular context (i.e., when specified
as a grouping variable).  Can you provide evidence (i.e., what specific
error/incorrect results do you get if you follow Pascal's advice) ?