Message-ID: <Pine.LNX.4.62.0504121536450.26563@bolker.zoo.ufl.edu>
Date: 2005-04-12T19:40:51Z
From: Ben Bolker
Subject: Fitting a mixed negative binomial model
This is a little bit tricky (nonlinear, mixed, count data ...) Off the
top of my head, without even looking at the documentation, I think your
best bet for this problem would be to use the weights statement to allow
the variance to be proportional to the mean (and add a normal error term
for individuals) -- this would be close to equivalent to the log-Poisson
model used by Elston et al. (Parasitology 2001, 122, 563-569, "Analysis of
aggregation, a worked example: numbers of ticks on red grouse chicks"),
and might do what you want.
--
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