Re: st: identifying observations where multiple conditions are met

[Richard Goldstein <richgold@ix.netcom.com>]

if I understand what you are asking for correctly, I would do the following:

gen byte mintype=min(type), by(id)
gen byte maxtype=max(type), by(id)
ta id if mintype==0 & maxtype==1

note that if there are a maximum of 2 occurrences of the id there are
ways to do this in one statement, but from what you said it appears that
id can occur more than 2 times

Rich

On 11/13/13, 3:14 PM, Michael McCulloch wrote:
> Hello,
> I have data of the structure:
> 	id 		(range 1 to 300)
> 	type 	(for each -id-, should equal only one of two values: 0 or 1).
> 
> In manual inspection of the data, I see instances exist where, for the same -id-, 
> 	some records have type==0, and  
> 	other records have type==1.
> 
> If I enter 
> 	. tab id if type==0 & type==1
> obviously "no observations" is returned.
> 
> How would I write a command in which I can tabulate all -id- for which some 
observations exist where type==0, and others where type==1? (At data entry,
-type- should have unique for each -id-.)
> 
> 
> Best wishes,
> Michael McCulloch
> 
> --
> Pine Street Foundation, since 1989
> 124 Pine Street | San Anselmo | California | 94960-2674  
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