Talk:Siegel–Tukey test

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i probably an error, at the end of the article, : "power is equal to 0.61%." it is probably more some thing like 61%, no ? al

math for U1 and U2 wrong[edit]

I don't know what the correct formulas are but the simple math for U1 and U2 seem to wrong as the calculation of the probability (if 9 is correct correct statistic) This math needs correction or deletion.

cause of this error?[edit]

I guess the cause of this error.

At first, when the number of all observations (N) is odd, the middle observation is thrown out[1]. So, the seventh element, 66 in group B, is thrown out, and the number of observations in the group B is five (n=7, m=5, and N=12).

Then, the sum of the ranks within each group and the U statistics are computed as follows:

Wa = 5+12+11+10+7+6+3 = 54
Wb = 1+4+8+9+2 = 24
U1 = 7*5+(7*(7+1)/2)-54=9
U2 = 7*5+(5*(5+1)/2)-24=26


U1*U2 = 9+26 = 35
n*m = 7*5 = 35

Additionally, I confirmed that U1+U2 and n*m are equivalent when N (or n+m) is even, because U1+U2=N(N+1)/2.

Is my guess is correct?

[1] J. D. Gibbons and S. Chakraborti, "Nonparametric Statistical Inference", Marcel Dekker Inc., p.330, 2003. (We can peek this page on Google :)) (talk) 11:10, 22 April 2009 (UTC) (only the section "cause of this error?")

As I like to say, our friend's English is better than my Italian. Nevertheless, I have rewritten the article to make the English more comprehensible. I have also clarified the U statistics. I did have to remove a couple of sentences that I could not understand at all. Markjoseph125 (talk) 17:58, 2 August 2009 (UTC)

  1. ^