Re: st: Question about duplicates and tag command

[Richard Williams <Richard.A.Williams.5@ND.Edu>]

At 04:48 AM 2/27/2006, Mosca, Ilaria wrote:
> Dear Statalisters,
>
> I have been working with a database in which I had to identify
> duplicates of institutions and afterwards count the number of
> institutions per year. I therefore wrote the following commands:
>
> . sort code
> . quietly by code: gen dup=cond(_N==1,0,_n)
> . drop if dup>1
> . gen id04==1 if year==2004
> . count if id04==1
>
> My problem is that EVERY TIME that I was running these commands, I
> obtained different results! Once the count command was 749, once 753,
> and so on. And this without any apparent reason.
See -help sort- and the -stable- option.  Sort orders can be 
different each time you run the -sort- command unless you use the 
-stable- option.


-------------------------------------------
Richard Williams, Notre Dame Dept of Sociology
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