question about an unbalanced design using lmer

Dear Xiyue and Thiery,

While more data points may affect the estimation process in that way 
they do not seem to affect the fixed-effects estimates in that way. To 
be more precise, the fixed effect estimate seems to correspond to the 
unweighted mean (i.e., the mean in which each level of the random effect 
is weighted equally) and not to the weighted mean (in which each data 
point is weighted equally).

I had a similar problem some time ago:
https://stat.ethz.ch/pipermail/r-sig-mixed-models/2014q3/022478.html

Thanks to the help of Jake Westfall I was able to get the desired result 
(i.e., a fixed-effect estimate corresponding to the weighted mean), by 
adding group size as fixed effect to my model, see:
https://stat.ethz.ch/pipermail/r-sig-mixed-models/2014q3/022481.html

There might be other approaches to achieve this as well (i.e., some 
post-fit weighting), but I am not sure how to implement this (perhaps 
using lsmeans somehow).

I hope this helps,
Henrik

Am 17.10.2016 um 11:09 schrieb Thierry Onkelinx:

question about an unbalanced design using lmer

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