Re: st: specification test after non-linear regression

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

--- On Wed, 16/6/10, Cindy Gao wrote:
> I am trying to find out how to do a specification test
> (e.g. to test whether specification is correct, omitted
> variables etc) after running a non-linear least squares
> regression. My regression command is of the form:
> 
> - nl (depvar = {b0} + {b1}*var1+ indicator*({b2} +
> {b3}*var1) + {b4}*var2 + {b5}*var3) -

There is no need to use -nl- here: this is just a simple
regression with an interaction terms:

*----------------- begin example ----------------------
sysuse auto, clear
nl (price = {b1}*mpg+ foreign*({b2} + {b3}*mpg) + {b0})
gen forXmpg = foreign * mpg
reg price mpg foreign forXmpg
*------------------- end example ----------------------
(For more on examples I sent to the Statalist see: 
http://www.maartenbuis.nl/example_faq )

So you can just use -regress- and all the post-estimation
commands that are avaialbe after that.

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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