R help - Dec 2010 - set Gamma parameters in glm model

Hello

I hope my question makes sense. It is possible to specify the shape paramenters
in a glm model with family Gamma?

Thanks in advance
Rosario

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Rosario Garcia Gil <M.Rosario.Garcia <at> slu.se> writes:
> 
> Hello
> 
> I hope my question makes sense. It is possible to specify the shape
paramenters in a glm model with family Gamma?
> 
  It doesn't look that way, but you can do a Gamma model with
a specified shape parameter (albeit much less efficiently) via

library(bbmle)
mle2(response~dgamma(scale=(1/invmu)/a,shape=a),
    parameters=list(invmu~pred1+pred2+...),
    start=list(mu=1,shape=0),
    data=...)