Assuming that you are using Stata 9.1 (Statalist convention)
or even Stata >= 7 this can be done much more simply.
foreach v in A B C D {
local x "`x' `v'"
regress y `x'
}
With strings always copy if you can, and
evaluate only if you must.
Thus
local x
is better style than
local x = ""
In the example above I assumed no prior use
of x.
Nick
[email protected]
[email protected]
> I would like to loop my estimations through an increasing number of
> variables, but I am having difficulty undating my varlist.
>
> For example, suppose there were four variable (A B C D) and I wish to
> estimate x on y where x is one of the four sets: "A", "A B",
> "A B C", and
> "A B C D".
>
> tokenize "A B C D"
> local i = 1
> local x = ""
> while i<=4 {
> local x = `x'+``i''
> regress y `x'
> local i=`i'+1
> }
>
> This program does not work because I can not get x to update.
*
* For searches and help try:
* http://www.stata.com/support/faqs/res/findit.html
* http://www.stata.com/support/statalist/faq
* http://www.ats.ucla.edu/stat/stata/