Stata The Stata listserver
[Date Prev][Date Next][Thread Prev][Thread Next][Date index][Thread index]

st: stepwise with if( exp)


From   Garry Anderson <[email protected]>
To   [email protected]
Subject   st: stepwise with if( exp)
Date   Thu, 23 Sep 2004 10:12:46 +1000

Hi Statalisters,

It seems that combining if( exp) with the sw command produces

varlist required
r(100);

For example,
use http://www.stata-press.com/data/r8/auto.dta

sw reg price mpg trunk if(mpg>20),pe(0.20)
varlist required
r(100);

reg price mpg trunk if(mpg>20)
produces results

sw reg price mpg trunk ,pe(0.20)
does forward selection, and produces results

sw reg price mpg trunk if (mpg>20),pe(0.20)
does forward selection, and produces results
(There is a space between if and the left bracket)

Therefore, it appears that -if(exp)- rather than -if (exp)- is causing the problem with the sw command. Hoever, -if(exp)- works with the reg command.

I am using the 23Jul executable and 01Sep updates.
Kind regards, Garry



© Copyright 1996–2024 StataCorp LLC   |   Terms of use   |   Privacy   |   Contact us   |   What's new   |   Site index