[R] classification table in logistic regression

[Thomas Lumley]

On Wed, 4 Sep 2002 idimakos at upatras.gr wrote:

> Friends,
>
> Is there an option (or options) to produce a classification table when
> running a logistic regression analysis?  Similar to the ctable option in
> proc logistic in SAS?
>

If you have a binary outcome it's very simple
	table(model$y,fitted(model)>threshold)
where threshold is the threshold for deciding whether a fitted value
should go to 1 or 0.  One natural default is
	threshold<-mean(fitted(model))
which makes the overall observed and predicted numbers equal.

	-thomas

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