Re: st: how to find out observations that id variables can't uniquely identify?

[Steve Nakoneshny <scnakone@ucalgary.ca>]

Hi Nina,

One way to easily identify your duplicates for further exploration would be to write -duplicates list applno productno-. This will simply list all records for which both of the listed variables are duplicated. If you wished to create a new indicator variable, -duplicates tag applno productno, gen(dup)- will do that.
Try -help duplicates- for more info.


On 2011-10-19, at 8:58 AM, Nina YIN wrote:

> Dear all,
> 
> I want to merge two large datasets, before I merge them, I checked
> whether id variables(applno productno) uniquely identify observations:
> "by applno productno:assert _N==1", it turns out "4 contradictions in
> 26586 by-groups ", then I want to figure out what's the problem with
> these 4 contradictions. However I don't know how to find out where
> they are? Do you have any suggestions? Thanks a lot!
> 
> 
> 
> -- 
> Best Regards,
> Nina YIN
> 
> 
> Toulouse School of Economics
> Manufacture des Tabacs
> 21 Allee de Brienne
> Toulouse, 31000, France
> Tel: 0033-(0)5 6123 8348
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