[R] Wilcoxon signed rank test and its requirements

[Atte Tenkanen]

Hi all,

I have a distribution, and take a sample of it. Then I compare that sample with the mean of the population like here in "Wilcoxon signed rank test with continuity correction":

> wilcox.test(Sample,mu=mean(All), alt="two.sided")

	Wilcoxon signed rank test with continuity correction

data:  AlphaNoteOnsetDists 
V = 63855, p-value = 0.0002093
alternative hypothesis: true location is not equal to 0.4115136 

> wilcox.test(Sample,mu=mean(All), alt = "greater")

	Wilcoxon signed rank test with continuity correction

data:  AlphaNoteOnsetDists 
V = 63855, p-value = 0.0001047
alternative hypothesis: true location is greater than 0.4115136 

What assumptions are needed for the population?
What can we say according these results?
p-value for the "less" is 0.999.

Thanks in advance,

Atte

Atte Tenkanen
University of Turku, Finland
Department of Musicology
+35823335278
http://users.utu.fi/attenka/