Economics should be open

March 26, 2009

Stata “unique” command helpful

Filed under: Stata — howardchong @ 9:58 pm

I just found the unique stata command.

PROBLEM: I have a correspondence table of companies to domains. One company can have multiple domains. I wanted a count of the number of unique companies.
SOLUTION: download the “unique” stata command. Install by running “ssc install unique”. You can also read more about it from the site:

ALTERNATIVE: I used to just do “keep company” and then “duplicates drop”. It was a hack, but it worked. If you have a small number, a easy way to do it is “tab company” and just count the lines.



  1. Here is sample output of the unique command:

    . unique company
    Number of unique values of company is 103
    Number of records is 202

    Comment by howardchong — March 26, 2009 @ 9:59 pm

  2. very helpful! THX!

    Comment by Daisy Lam — August 30, 2012 @ 7:27 pm

  3. awesome

    Comment by MrDesignDataAnalysis — January 20, 2014 @ 3:53 am

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