gov.sandia.cognition.statistics.method

Class MannWhitneyUConfidence.Statistic

java.lang.Object

gov.sandia.cognition.util.AbstractCloneableSerializable

gov.sandia.cognition.statistics.method.AbstractConfidenceStatistic

gov.sandia.cognition.statistics.method.MannWhitneyUConfidence.Statistic

All Implemented Interfaces:

ConfidenceStatistic, CloneableSerializable, java.io.Serializable, java.lang.Cloneable

Direct Known Subclasses:

ReceiverOperatingCharacteristic.Statistic

Enclosing class:

MannWhitneyUConfidence

public static class MannWhitneyUConfidence.Statistic
extends AbstractConfidenceStatistic

Statistics from the Mann-Whitney U-test

See Also:

Serialized Form

Field Summary

Fields inherited from class gov.sandia.cognition.statistics.method.AbstractConfidenceStatistic

nullHypothesisProbability

Constructor Summary

Constructors

Constructor and Description
Statistic(double sum1, int N1, double sum2, int N2) Creates a new instance of Statistic
Statistic(MannWhitneyUConfidence.Statistic other) Copy Constructor

Method Summary

Modifier and Type	Method and Description
static double	computeNullHypothesisProbability(double z) Computes the p-value for the test, given the z-value
static double	computeU(double sum1, int N1, double sum2, int N2) Computes the U-statistic, the minimum rank sum above "chance"
static double	computeZ(double U, int N1, int N2) Computes the z-value, used in the UnivariateGaussian CDF
int	getN1() Getter for N1
int	getN2() Getter for N2
double	getTestStatistic() Gets the statistic from which we compute the null-hypothesis probability.
double	getU() Getter for U
double	getZ() Getter for z
protected void	setN1(int N1) Setter for N1
protected void	setN2(int N2) Setter for N2
protected void	setU(double U) Setter for U
protected void	setZ(double z) Setter for z

Methods inherited from class gov.sandia.cognition.statistics.method.AbstractConfidenceStatistic

getNullHypothesisProbability, setNullHypothesisProbability, toString

Methods inherited from class gov.sandia.cognition.util.AbstractCloneableSerializable

clone

Methods inherited from class java.lang.Object

equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from interface gov.sandia.cognition.util.CloneableSerializable

clone

Constructor Detail

Statistic

public Statistic(double sum1,
                 int N1,
                 double sum2,
                 int N2)

Creates a new instance of Statistic

Parameters:

sum1 - Rank sum for data1

N1 - Number of samples in data1

sum2 - Rank sum for data2

N2 - Number of samples in data2

Statistic

public Statistic(MannWhitneyUConfidence.Statistic other)

Copy Constructor

Parameters:

other - Statistic to copy

Method Detail

computeU

public static double computeU(double sum1,
                              int N1,
                              double sum2,
                              int N2)

Computes the U-statistic, the minimum rank sum above "chance"

Parameters:

sum1 - Rank-sum value for data1

N1 - Number of samples in data1

sum2 - Rank-sum value for data2

N2 - Number of samples in data2

Returns:

U statistic, minimum rank sum above "chance"

computeZ

public static double computeZ(double U,
                              int N1,
                              int N2)

Computes the z-value, used in the UnivariateGaussian CDF

Parameters:

U - U statistic, minimum rank sum above "chance"

N1 - Number of samples in data1

N2 - Number of samples in data2

Returns:

z-value for a UnivariateGaussian CDF, number of standard deviations away from chance

computeNullHypothesisProbability

public static double computeNullHypothesisProbability(double z)

Computes the p-value for the test, given the z-value

Parameters:

z - z-value for a UnivariateGaussian CDF, number of standard deviations away from chance

Returns:

Chance that the null hypothesis is correct

getU

public double getU()

Getter for U

Returns:

U statistic, minimum rank sum above "chance"

setU

protected void setU(double U)

Setter for U

Parameters:

U - U statistic, minimum rank sum above "chance"

getZ

public double getZ()

Getter for z

Returns:

z-value for a UnivariateGaussian CDF, number of standard deviations away from chance

setZ

protected void setZ(double z)

Setter for z

Parameters:

z - z-value for a UnivariateGaussian CDF, number of standard deviations away from chance

getN1

public int getN1()

Getter for N1

Returns:

Number of samples in data1

setN1

protected void setN1(int N1)

Setter for N1

Parameters:

N1 - Number of samples in data1

getN2

public int getN2()

Getter for N2

Returns:

Number of samples in data2

setN2

protected void setN2(int N2)

Setter for N2

Parameters:

N2 - Number of samples in data1

getTestStatistic

public double getTestStatistic()

Description copied from interface: ConfidenceStatistic

Gets the statistic from which we compute the null-hypothesis probability. In an ANOVA, this would be the "F" statistic. In a t-test, this would be the "t" value. And so forth.

Returns:

Confidence statistic used to compute the null-hypothesis probability.