[R] Calculating dispersion in glm

[Thomas Lumley]

On Fri, 23 Aug 2002, David Mackie wrote:

> Hi all,
>
> How is dispersion calculated within the glm function in R ?
>

It isn't.

It's calculated within the summary.glm function (or supplied by the user).
as
 sum(object$weights * object$residuals^2)/df.r

which works out to be equal to the mean square of the Pearson residuals.

	-thomas

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