st: Checking if one variable = any of the values of another

[Maria Davydenko <maria.davydenko@gmail.com>]

Hey all,

I have a Twitter data set where each observation includes the user who
tweeted (var from_user), what they tweeted (var text) as well as
variables m1 through m11 (up to 11 users they mentioned in var text).
I want to create an indicator variable grpment that =1 if any of the m
(match) variables for a given observation are equal to any of the
other values of from_user.  Here's what it looks like:

from_user	text		m1	m2 …11	grpment
P1		@P2		P2			1
P2		@other				        0
P3		@P1 @P2	P1	P2		1

In human speak, I want to see if the from_user is mentioning any of
the other from_users, based on the 11 different m variables.

I have it all figured out except the grpment element.  So far, I've
been playing with loops but can't think of anything short of a giant
macro that could make this work. If you have any insight, it would be
much appreciated!

Thanks,

Maria

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