st: Re: dummy variable with overlapping if conditions

[Kit Baum <baum@bc.edu>]

It is useful to note that a binary variable of this sort is the  
intersection of the sets defined by each dummy. Intersection of sets  
in binary arithmetic is done by multiplying, or with the AND operator  
(&). The union of sets -- true if either is true -- is done with the  
OR operator (|). Stata does not contain an exclusive OR operator  
(XOR), but one can readily be fashioned by adding the dummies:

gen xor12 = cond(dum1+dum2==1, 1, 0)


Kit Baum, Boston College Economics
http://ideas.repec.org/e/pba1.html
An Introduction to Modern Econometrics Using Stata:
http://www.stata-press.com/books/imeus.html


On Sep 25, 2006, at 2:33 AM, statalist-digest wrote:


> I will just add that Philipp's code generates missing where the  
> condition is not met and these would have to be replaced
> with 0 to make it a dummy variable. This two step can be avoided if  
> this code is modified to be
>
> gen  cl1 = conlab == 1 & (clmarg>=.95 & clmarg<=1.05)
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