st: Question About Using Permute Command

[Michael Horowitz <horom@sas.upenn.edu>]

I am interested in using the permute command to re-randomize an IV of 
interest as a robustness test. The materials on it seem a bit sparse, 
however, and I was wondering if someone could assist with the correct 
syntax. Here are the two possibilities I have come up with:

1. permute IV (the one I am randomizing) "regress DV IV control1 
control2 control3" _b, reps(10000)

2. permute IV (the one I am randomizing) _b, reps(10000) 
saving(permtest1, replace): regress DV IV control1 control2 control3

Both seem to run, but they produce slightly different results and I am 
not sure which is right. I know people are busy, but I would appreciate 
any insight on which syntax is correct - or if both are wrong, what to 
use instead. Thanks very much!

Michael Horowitz



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