RE: st: discriminatory power of a probit model

["Verkuilen, Jay" <JVerkuilen@gc.cuny.edu>]

Maarten buis wrote:

>>The problem with the proportion correctly classified is that it
depends on the distribution of your dependent variable: if success is
rare and everybody is classified as a failure than the proportion
correclty specified is still large.<< 

Indeed this is a big problem with the whole classification table
approach. Long (1998) discusses this point quite nicely but if you want
to read one of the classics, look at the article by Meehl and Rosen
(1955) (Psych. Bull.) where the base rate problem was first probed in
detail.

Jay

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