[R] Fitting a mixed negative binomial model

Ben Bolker bolker at zoo.ufl.edu
Tue Apr 12 21:40:51 CEST 2005


   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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