[R-sig-ME] REML estimates not given

[Renwick, A. R.]

I am running an lmer model using a poisson distribution and log link.  However, when I ask REML=TRUE I do not get a REML estimate only the ML estimate.

For example:
mix3<-lmer(RoundedOverlap~Sex+Margin+sess+Sex:Margin+(1|Site), family=poisson, data=both,REML=TRUE)
 mix3 at deviance
        ML       REML
159.158662         NA

mix4<-lmer(RoundedOverlap~Sex+Margin+sess+Sex:Margin+(1|Site), family=poisson, data=both,REML=FALSE)
 mix4 at deviance
        ML       REML
159.158662         NA

I am using both the latest R (R version 2.7.2 ) and lme4 package

I wasw ondering if anybody knows why REML does not seem to be being used and if this is an issue with poisson distributed models in general.
Many thanks
Anna


Anna Renwick
Zoology Building
School of Biological Sciences
University of Aberdeen
Aberdeen
AB24 2TZ


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