Re: st: conditional test after logistic regression

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

--- On Wed, 14/4/10, Ricardo Ovaldia wrote:
> The article that I am reading states the null in terms of
> beta - Ho: (Bx|By)=0 
> 
> Would your answer change if y=x^2?
> 
> So that the model would be:
> 
> logistic case x x2
> 
> where x2=x^2
> 
> and the null is now,  Ho: (Bx2|Bx)=0 ?

Ok, I think I see what you mean. I would then state the H0 as
(Bx2|Bx=0)=0 or probably more interesting is (Bx|Bx2=0)=0. 
The latter hypothesis would mean whether there is an effect, 
given that the effect is non-quadratic. You could test that 
as follows:

logistic case x 
test x

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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