I have a question for Splus experts:
Burnham and Anderson, in their book "Model selection and inference" about
Akaike Information Criteria (AIC), said that (as of 1989) there are no
statistical software packages that compute QAIC, the specific form of AIC
calculated when using the quasi function in generalized linear models. When
I use Splus 2000 to use quasi, it gives me an AIC value under the "step"
function, but can I assume this is the correct QAIC value? Or do I need to
calculate it separately by hand? If I need to calculate it, I need the
log-likelihood value for the model, which I need to divide by the dispersion
parameter (c-hat). Is there a straightforward way of obtaining the
log-likelihood in the output?
This is stumping some very competent statisticians and SPlus users -- any
advice would be appreciated. Thank you!
Roz Renfrew
Rosalind Renfrew, PhD dissertator
Department of Wildlife Ecology
University of Wisconsin - Madison
1630 Linden Drive
Madison, WI 53706
608-263-7595
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