"Intercept" in dissection report

["Adrian E. Gould" <ag...@cj.com>]

The intercept sometimes appears in model dissection reports. What can the intercept's weight tell me about my model?




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Re: "Intercept" in dissection report

[Ted Dunning <te...@gmail.com>]

It tells you the base rate of positive cases.  The scale is log-odds and if
you have any very common features then those should be included in this
estimate.  L_1 regularization will tend to prefer the intercept over any
feature that has less than 100% prevalence.  If you have features with 100%
prevalence and constant weight then you might as well eliminate them anyway.

To convert a log-odds value x to a probability, use 1/(1+exp(-x))


On Wed, Dec 15, 2010 at 12:06 PM, Adrian E. Gould <ag...@cj.com> wrote:

> The intercept sometimes appears in model dissection reports. What can the
> intercept's weight tell me about my model?
>
>
>