st: Re: generating random variable

["Michael Blasnik" <michael.blasnik@verizon.net>]

This seems fairly simple:

expand 2
gen random=uniform()
bysort id bl set (random): gen byte choice=_n==_N

To make it 3 alternatives, just change expand 2 to expand 3.  There is really no 
point in creating the random variable in this approach since all observations 
within a set are identical, so you could just assign it to the last observation 
without randomly sorting.

Michael Blasnik

----- Original Message ----- 
From: "Mentzakis, Emmanouil" <e.mentzakis@abdn.ac.uk>
To: <statalist@hsphsun2.harvard.edu>
Sent: Tuesday, April 03, 2007 12:26 PM
Subject: st: generating random variable



> Dear all,
>
> I need to create a variable "choice" that will take the value of 0 or 1
> randomly (but in each set there has to be one occurrence of "one" and
> one occurrence of "zero"). I need the various respondents (id) to have
> different "choice" for the same "bl and "set", but I assume this is
> taken care by the random nature of the creation of the "choice"
> variable.
>
> id bl set choice
> 1 1 1 1
> 1 1 1 0
> 1 1 2 0
> 1 1 2 1
> 1 1 3 0
<snip>
> I would also like to create the same kind of "choice" variable but where
> each "set" has three alternatives (one occurrence of "one" and two
> occurrences of "zero"), i.e.
<snip>
> Any help would be much appreciated.
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