st: Find all subsets of variables

[junin <dv.junin@gmail.com>]

Dear all,

i want to find out all subsets of a given set of variables for model
testing. As an example:

A set of variables var1 var2 var3 var4 should give me:
var1 var2 var3 var4
var1 var2 var3
var1 var2 var4
var1 var3 var4
var1 var4
var1
var2 var3 var4

and so forth.

I would like to test all possible model configurations. Is there a
command in Stata, which could be convenient to use?

Thank you for any help,

dirk
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