0
$\begingroup$

The negative binomial has two parameter in its distribution. Neg bin has a scale and a probability parameter. I’d imagine the scale parameter estimated in poisson regression is only one of them. Does running poisson regression give me those two parameters in the negbin?

$\endgroup$

1 Answer 1

0
$\begingroup$

It is indeed the case that if you use family=negative.binomial (from the MASS package) that you need to specify theta. You could try running GEE fits in a loop or an optimizer with a range of theta values and selecting the one that maximizes some goodness-of-fit statistic (this is what MASS::glm.nb does).

I would suggest looking into Zuur et al's book on mixed models in ecology to see if there is anything useful there.

Ben Bolker

https://stat.ethz.ch/pipermail/r-help/2011-June/282116.html

$\endgroup$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.