scipy.stats.wilcoxon¶
- scipy.stats.wilcoxon(x, y=None)[source]¶
Calculate the Wilcoxon signed-rank test.
The Wilcoxon signed-rank test tests the null hypothesis that two related samples come from the same distribution. It is a a non-parametric version of the paired T-test.
Parameters : x : array_like
The first set of measurements.
y : array_like, optional
The second set of measurements. If y is not given, then the x array is considered to be the differences between the two sets of measurements.
Returns : z-statistic : float
The test statistic under the large-sample approximation that the signed-rank statistic is normally distributed.
p-value : float
The two-sided p-value for the test.
Notes
Because the normal approximation is used for the calculations, the samples used should be large. A typical rule is to require that n > 20.
References
[R154] http://en.wikipedia.org/wiki/Wilcoxon_signed-rank_test
