st: Re: picking at random

[baum <baum@bc.edu>]

--On Wednesday, June 12, 2002 2:33 -0400 Yanjun wrote:

> We have say, by one id, four observations under a variable.  We want
> STATA  to randomly pick one observation each time it is asked.  We want
> to use the  randomly picked observation for each id in regression.
>
> Any information will be greatly appreciated!  Thanks.
No doubt someone will improve on this, but it works, even if there are 
unbalanced groups...
Assume your id variable is named 'group':

g rr=uniform()
by group: egen rrm=min(rr)
by group: g select=(rr==rrm)
reg .... if (select)

Kit
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