[R-sig-ME] multinomial mixed effects models

[Austin Frank]

Hello!

I and several of my colleagues are wondering whether it is possible to
use any of the methods of lme4 as it exists now to fit a mixed effects
model with a response variable drawn from a multinomial distribution.
glm does not include a multinomial family, so if it is possible to
accomplish this I'm not sure how to do so.  Packages that do allow
multinomial response variables (like multinomRob) don't seem to allow
for the inclusion of random effects.

If it is not currently possible to fit a data set with a categorical
dependent variable with more than two levels, might this be possible in
the forthcoming update to lme4?

Finally, if it isn't possible now and won't be in the next version of
the package either, would someone be willing to explain the conceptual
or technical difficulties associated with including a response variable
from a multinomial distribution in a mixed effects model?

Thanks for any help,
/au

-- 
Austin Frank
http://aufrank.net
GPG Public Key (D7398C2F): http://aufrank.net/personal.asc