[R-sig-ME] testing random effect

[Douglas Bates]

2008/2/16 Maria Silvina Fenoglio <msfeno at yahoo.com.ar>:
> Hi all,
>   I am trying to test the significance of the random effect in the following model but I didn't find the way to do that.
> I think that I can do it with LRT, removing the random effect and comparing both models, but an error appears...
>   Can anybody help me with that?
>
>   mod<-lmer(Riqsp~Distpza+logtam+logaisl+Densmin+(1|Sitio),sil,family=poisson,method="ML")

Could you give us a bit more detail, please?  How did you try to
perform the likelihood ratio test?

If possible, could you make your data available so we can check the
fits against different versions of the lme4 package?