public class MannWhitneyUTest extends Object
Constructor and Description 

MannWhitneyUTest()
Create a test instance using where NaN's are left in place and ties get
the average of applicable ranks.

MannWhitneyUTest(NaNStrategy nanStrategy,
TiesStrategy tiesStrategy)
Create a test instance using the given strategies for NaN's and ties.

Modifier and Type  Method and Description 

double 
mannWhitneyU(double[] x,
double[] y)
Computes the MannWhitney
U statistic comparing mean for two independent samples possibly of
different length.

double 
mannWhitneyUTest(double[] x,
double[] y)
Returns the asymptotic observed significance level, or
pvalue, associated with a MannWhitney
U statistic comparing mean for two independent samples.

public MannWhitneyUTest()
public MannWhitneyUTest(NaNStrategy nanStrategy, TiesStrategy tiesStrategy)
nanStrategy
 specifies the strategy that should be used for Double.NaN'stiesStrategy
 specifies the strategy that should be used for tiespublic double mannWhitneyU(double[] x, double[] y) throws NullArgumentException, NoDataException
This statistic can be used to perform a MannWhitney U test evaluating the null hypothesis that the two independent samples has equal mean.
Let X_{i} denote the i'th individual of the first sample and Y_{j} the j'th individual in the second sample. Note that the samples would often have different length.
Preconditions:
x
 the first sampley
 the second sampleNullArgumentException
 if x
or y
are null
.NoDataException
 if x
or y
are zerolength.public double mannWhitneyUTest(double[] x, double[] y) throws NullArgumentException, NoDataException, ConvergenceException, MaxCountExceededException
Let X_{i} denote the i'th individual of the first sample and Y_{j} the j'th individual in the second sample. Note that the samples would often have different length.
Preconditions:
Ties give rise to biased variance at the moment. See e.g. http://mlsc.lboro.ac.uk/resources/statistics/Mannwhitney.pdf.
x
 the first sampley
 the second sampleNullArgumentException
 if x
or y
are null
.NoDataException
 if x
or y
are zerolength.ConvergenceException
 if the pvalue can not be computed due to a
convergence errorMaxCountExceededException
 if the maximum number of iterations
is exceededCopyright © 20032012 The Apache Software Foundation. All Rights Reserved.