Functions
template<domain D :shared3p >
D float32	mannWhitneyU (D int32[[1]] sample1, D bool[[1]] ia1, D int32[[1]] sample2, D bool[[1]] ia2, bool correctRanks, int64 alternative)

template<domain D :shared3p >
D float64	mannWhitneyU (D int64[[1]] sample1, D bool[[1]] ia1, D int64[[1]] sample2, D bool[[1]] ia2, bool correctRanks, int64 alternative)

template<domain D :shared3p >
D float32	mannWhitneyU (D float32[[1]] sample1, D bool[[1]] ia1, D float32[[1]] sample2, D bool[[1]] ia2, bool correctRanks, int64 alternative)

template<domain D :shared3p >
D float64	mannWhitneyU (D float64[[1]] sample1, D bool[[1]] ia1, D float64[[1]] sample2, D bool[[1]] ia2, bool correctRanks, int64 alternative)

Detailed Description

Perform Mann-Whitney U test.

Note: D - shared3p protection domain; Supported types - int32 / int64 / float32 / float64; The t-test requires the populations to be normally distributed. If the populations cannot be assumed to be normally distributed but are ordinal then the Mann-Whitney U or Wilcoxon rank-sum test can be used instead.

Parameters

sample1	- first sample
ia1	- vector indicating which elements of the first sample are available
sample2	- second sample
ia2	- vector indicating which elements of the second sample are available
correctRanks	- indicates if the equal sample values should be ranked correctly. If they are not the test is more conservative but faster.
alternative	- the type of alternative hypothesis. Less - mean of sample1 is less than mean of sample2, greater - mean of sample1 is greater than mean of sample2, two-sided - means of sample1 and sample2 are different

Returns: returns a vector where the first element is the test statistic and the second element is the z-score. The z-score is continuity corrected. The z-score is an approximation and is only correct when the samples are large and the significance level is not very low.

Function Documentation