st: count same strings among variables

[Antonio Acconcia <acconcia@unina.it>]

Hi, Statalist,

I have a number of variables, say x1-x10, with different number of  
observations all containing strings. I need to select those strings  
that (or simply to count how many strings) are present in x1-x2,  
x1-x3, and so on; how many are present in x2-x3, x2-x4, and so on  
....but not in x1 ..... The same string can appear at different lines  
(say observation 1 for x1 and observation 3 for x2).

I'm writing to ask whether there is a way to do this.

Thanks a lot.

Antonio


  ---------------------------------------
  Antonio Acconcia
  CSEF - Dipartimento di Economia
  Università di Napoli Federico II
  via Cinthia, 45 (Monte S.Angelo)
  80126 Napoli - Italia
  Tel: +39-81- 675096
  Fax: +39-81-7663540


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