R devel - Apr 2003 - kendall's tau-b computation (PR#2742)

Full_Name: Dan Field
Version: 1.6.2
OS: N/A
Submission from: (NULL) (209.115.168.187)



In kendall.c (library is ctest), the limits for the first loop in routine
kendall_tau run from 0 through n-1, and the inner loop runs from 0 through i-1. 
This causes the each pair at index i to be compared with itself; my
understanding is that there should only be n*(n-1)/2 pairs under consideration
for concordance, discordance, and ties.

dan.field@av.com writes:
> In kendall.c (library is ctest), the limits for the first loop in routine
> kendall_tau run from 0 through n-1, and the inner loop runs from 0 through
i-1.
> This causes the each pair at index i to be compared with itself; my
> understanding is that there should only be n*(n-1)/2 pairs under
consideration
> for concordance, discordance, and ties.
??? 

Are you saying that j==i becomes true, when j runs from 0 to i-1?

-- 
   O__  ---- Peter Dalgaard             Blegdamsvej 3  
  c/ /'_ --- Dept. of Biostatistics     2200 Cph. N   
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