Re: st: RE: mlogit problem with "predict"

[Richard Williams <Richard.A.Williams.5@ND.edu>]

At 10:04 AM 8/7/2007, Sheela Athreya wrote:
> The idea that maybe I have an (almost) perfect prediction occurred to
> me too, but I don't know how to investigate it. Perhaps there is an
> equivalent test to -tab tax pc- that allows me to look at
> quantitative variables for anything that is off?
You could try something like

bysort y: sum x1 x2 x3 .

Look for x's with little or no variability within a category of 
y.  Or, maybe try

bysort y: corr x1 x2 x3

and see if there is extreme multicollinearity within a category of y.



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Richard Williams, Notre Dame Dept of Sociology
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