Re: st: conditional test after logistic regression

[Maarten buis <maartenbuis@yahoo.co.uk>]

--- On Wed, 14/4/10, Ricardo Ovaldia wrote:
> If I fit:
> 
> . logistic case x y
> 
> I can test the null Ho:Bx=0, By=0 using:
> 
> . test x y
> 
> How can I test the null Ho: (Bx|By)=0 ?

I am guessing you want to condition on y 
an not on By. In that case the answer can 
be pretty easy: you haven't included an 
interaction term between x and y, so that 
is just

text x

However, this will only work if you are
interested in effects in terms of odds
ratios or log odds ratios. Things get 
more complicated when you want to look
at marginal effects.

Hope this helps,
Maarten

--------------------------
Maarten L. Buis
Institut fuer Soziologie
Universitaet Tuebingen
Wilhelmstrasse 36
72074 Tuebingen
Germany

http://www.maartenbuis.nl
--------------------------


      

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