[R-sig-ME] between-blocks variation in intercepts estimated as zero by lmer in RB design???

[David Duffy]

On Mon, 7 Feb 2011, Duncan Mackay wrote:

> Hello, I am having difficulty understanding why lmer is estimating the 
> variation among intercepts of random groups (blocks) as zero in the 
> following case:-

Negative intracluster correlation.

-- 
| David Duffy (MBBS PhD)                                         ,-_|\
| email: davidD at qimr.edu.au  ph: INT+61+7+3362-0217 fax: -0101  /     *
| Epidemiology Unit, Queensland Institute of Medical Research   \_,-._/
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