[R-sig-ME] 2-level null versus 1 level null model

[David Duffy]

On Fri, 22 Jun 2012, Ben Pelzer wrote:

> one <- rep(1, length(Y))
>
> M01level <-  lmer (Y ~ (1 | one), REML=FALSE)
> M02level <-  lmer (Y ~ (1 | one) + (1 | country), REML=FALSE)
> anova(M02level, M01level)
>
> This seams to work properly. However, I don't feel really convinced by this 
> solution yet. Is it to be trusted, or is there a much simpler way to test 
> this using lmer? Thanks for any help!!!

Yes, this works.  The RLRsim package does an exact test - the 
distribution of the likelihood ratio test isn't straightforward (at the 
very least it's a mixture of chi-squares).

Cheers, David Duffy.