[R] GLM family variance function

Thomas Lumley tlumley at u.washington.edu
Mon May 13 18:31:52 CEST 2002


On 13 May 2002, Ernesto Jardim wrote:

> Hi
>
> Still strugling with GLMs.
>
> I need to use a different variance function for the gamma family. Has
> far has I understand, assuming Y~G(\mu,\nu), the glm function uses
> V(\mu)=\mu^2 , but I need to use V(\mu)=\mu^2/\nu. I have a problem of
> variance proportional to the mean.

family=quasipoisson() has variance proportional to mean

	-thomas


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