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structured random effects

4 messages · David Firth, Spencer Graves, Douglas Bates

#
Are there facilities in R or packages to estimate the parameters of a 
(generalized) linear mixed model like this one: the design is crossed, 
and response $y_{ij}$ relates to fixed and random effects through a 
linear predictor
\[
       \eta_{ij} = \beta x_{ij} + U_i - U_j
\]
where $U_1, U_2, \ldots$ are iid $N(0, \tau^2)$.

Any suggestions would be welcomed.

David

Professor David Firth
Dept of Statistics
University of Warwick
Coventry CV4 7AL
United Kingdom

Voice: +44 (0)247 657 2581
Fax:   +44 (0)247 652 4532
Web:   http://www.warwick.ac.uk/go/dfirth
#
Have you considered "lme"?  For applications like this, I highly 
recommend Pinheiro and Bates (2000) Mixed-Effects Models in S and S-Plus 
(Springer).  I failed to produce anything with "lme" until I read this 
book. 

      hope this helps.  spencer graves
David Firth wrote:

            
#
Spencer Graves <spencer.graves at pdf.com> writes:
Actually lme is better suited to nested designs than to crossed
designs and lme doesn't handle generalized linear mixed models.

GLMM from package lme4 does handle generalized linear mixed models but
does not handle crossed random effects easily.

I'm working on code that will handle nested, crossed and partially
crossed random effects but it will be some time before it appears in a
finished package

  
    
#
Thanks to Douglas and Spencer for their helpful replies.

I take that as a fairly authoritative "no" to my question!  The 
difficulty
in the model I mentioned is not only the crossed design, but the
"homologous" factors (ie i and j take the same values),
and U_i - U_j with the *same* "U" variable
appearing twice with different subscripts in the predictor.

Thanks again -- I am happy to know that If I work on this I'm not
reinventing what already exists.

Best regards,
David
On Friday, Feb 6, 2004, at 18:28 Europe/London, Douglas Bates wrote: