Talk:Kendall tau rank correlation coefficient

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Mathematics rating:	Start Class	Low Priority	Field: Probability and statistics
Please update this rating as the article progresses, or if the rating is inaccurate. Click to show/hide comments. Please add to or update the comments to suggest improvements to the article. Geometry guy 23:52, 17 June 2007 (UTC)

Contents 1 Error in equation? 2 Error in explanation 3 Example 4 Significance tests

[edit] Error in equation?

According to http://www.rsscse.org.uk/TS/bts/noether/text.html and my experiments, I think the equation should be 1 - 4P/n(n-1) NOT 4P/n(n-1) - 1 —Preceding unsigned comment added by 74.95.2.89 (talk) 23:35, 11 December 2007 (UTC)

142.103.8.44 (talk) 23:16, 1 May 2008 (UTC) I'm pretty sure that works.

[edit] Error in explanation

The last paragraph of the definition has a problem: it says

P can also be interpreted as the number of concordant pairs subtracted by the number of discordant pairs.

This can't be literally true: P (as defined above) is a positive number, while this subtraction doesn't have to be.

Instead, while tau = 2P/N-1 (when N=n*(n-1)/2)), if we write S="number of concordant pairs subtracted by the number of discorant pairs", I think that tau = S/N, so that we have S=(2P-N).

Or am I missing something?

Nyh

[edit] Example

shouldn't the example be P = 5 + 4 + 4 + 4 + 3 + 1 + 0 + 0 = 22. instead of P = 5 + 4 + 5 + 4 + 3 + 1 + 0 + 0 = 22?

Sboehringer 17:00, 5 March 2007 (UTC)

Example as described on main page appears to be correct -- —Preceding unsigned comment added by 76.31.253.197 (talk) 13:43, 14 April 2008 (UTC)

[edit] Significance tests

Article needs some discussion of how to generate p-values in order for hypothesis testing. —Preceding unsigned comment added by 128.200.138.197 (talk) 17:55, August 27, 2007 (UTC)