com.numericalmethod.suanshu.stats.test.variance
Class Levene

java.lang.Object
  com.numericalmethod.suanshu.stats.test.HypothesisTest
      com.numericalmethod.suanshu.stats.test.variance.Levene

public class Levene
extends HypothesisTest

The Levene test tests for the equality of variance of groups. Levene's test does not require normality of the underlying data.

The R equivalent function is levene.test.

See Also:

• Wikipedia: Levene's test
• Levene Test for Equality of Variances

Nested Class Summary

static class

Levene.Type the implementations available when computing the absolute deviations

Field Summary

double	df1 the degree of freedoms
double	df2 the degree of freedoms

Fields inherited from class com.numericalmethod.suanshu.stats.test.HypothesisTest

k, N, pValue, testStatistics

Constructor Summary

Levene(double... samples)
Perform the Levene test to test for homeogeneity of variance across groups.

Levene(Levene.Type type, double[]... samples)
Perform the Levene test to test for homeogeneity of variance across groups.

Method Summary

java.lang.String	alternativeHypothesis() Get a description of the alternative hypothesis.
java.lang.String	nullHypothesis() Get a description of the null hypothesis.

Methods inherited from class com.numericalmethod.suanshu.stats.test.HypothesisTest

oneSidedPvalue, pValue, rejectNull, testStatistics

Methods inherited from class java.lang.Object

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

Field Detail

df1

public final double df1

the degree of freedoms

df2

public final double df2

the degree of freedoms

Constructor Detail

Levene

public Levene(double... samples)

Perform the Levene test to test for homeogeneity of variance across groups.

The absolute deviations are computed from the medians.

Parameters:

samples - samples

Levene

public Levene(Levene.Type type,
              double[]... samples)

Perform the Levene test to test for homeogeneity of variance across groups.

Parameters:

type - the implementation chosen

samples - samples

Method Detail

nullHypothesis

public java.lang.String nullHypothesis()

Description copied from class: HypothesisTest

Get a description of the null hypothesis.

Specified by:

nullHypothesis in class HypothesisTest

Returns:

the null hypothesis description

See Also:

Wikipedia: Null hypothesis

alternativeHypothesis

public java.lang.String alternativeHypothesis()

Description copied from class: HypothesisTest

Get a description of the alternative hypothesis.

Specified by:

alternativeHypothesis in class HypothesisTest

Returns:

the alternative hypothesis description

See Also:

Wikipedia: Alternative hypothesis