edu.udo.cs.yale.operator.validation.significance
Class TTestSignificanceTestOperator

java.lang.Object
  edu.udo.cs.yale.operator.Operator
      edu.udo.cs.yale.operator.validation.significance.SignificanceTestOperator
          edu.udo.cs.yale.operator.validation.significance.TTestSignificanceTestOperator

All Implemented Interfaces:

ConfigurationListener

public class TTestSignificanceTestOperator
extends SignificanceTestOperator

Determines if the null hypothesis (all actual mean values are the same) holds for the input performance vectors. This operator uses a simple (pairwise) t-test to determine the probability that the null hypothesis is wrong. Since a t-test can only be applied on two performance vectors this test will be applied to all possible pairs. The result is a significance matrix. However, pairwise t-test may introduce a larger type I error. It is recommended to apply an additional ANOVA test to determine if the null hypothesis is wrong at all.

Version:

$Id: TTestSignificanceTestOperator.java,v 1.5 2006/03/21 15:35:53 ingomierswa Exp $

Author:

Ingo Mierswa

Nested Class Summary

class

TTestSignificanceTestOperator.TTestSignificanceTestResult

Constructor Summary

TTestSignificanceTestOperator(OperatorDescription description)

Method Summary

int	getMaxSize() Returns the maximum number of performance vectors which can be compared by this significance test.
int	getMinSize() Returns the minimum number of performance vectors which can be compared by this significance test.
private double	getProbability(PerformanceCriterion pc1, PerformanceCriterion pc2)
SignificanceTestResult	performSignificanceTest(PerformanceVector[] allVectors, double alpha) Returns the result of the significance test for the given performance vector collection.

Methods inherited from class edu.udo.cs.yale.operator.validation.significance.SignificanceTestOperator

apply, getInputClasses, getOutputClasses, getParameterTypes

Methods inherited from class edu.udo.cs.yale.operator.Operator

addError, addValue, addWarning, apply, checkDeprecations, checkIO, checkProperties, clearErrorList, cloneOperator, createExperimentTree, createExperimentTree, createFromXML, createMarkedExperimentTree, delete, experimentFinished, experimentStarts, getAddOnlyAdditionalOutput, getApplyCount, getDeliveredOutputClasses, getDeprecationInfo, getDesiredInputClasses, getErrorList, getExperiment, getInnerOperatorsXML, getInput, getInput, getInput, getInputDescription, getIOContainerForInApplyLoopBreakpoint, getName, getNumberOfSteps, getOperatorClassName, getOperatorDescription, getParameter, getParameterAsBoolean, getParameterAsColor, getParameterAsDouble, getParameterAsFile, getParameterAsInt, getParameterAsString, getParameterList, getParameters, getParameterType, getParent, getStartTime, getStatus, getUserDescription, getValue, getValues, getXML, hasBreakpoint, hasBreakpoint, hasInput, inApplyLoop, isEnabled, isParameterSet, logMessage, performAdditionalChecks, register, remove, rename, resume, setBreakpoint, setEnabled, setExperiment, setInput, setListParameter, setOperatorParameters, setParameter, setParameters, setParent, setUserDescription, toString, writeXML

Methods inherited from class java.lang.Object

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

Constructor Detail

TTestSignificanceTestOperator

public TTestSignificanceTestOperator(OperatorDescription description)

Method Detail

performSignificanceTest

public SignificanceTestResult performSignificanceTest(PerformanceVector[] allVectors,
                                                      double alpha)

Description copied from class: SignificanceTestOperator

Returns the result of the significance test for the given performance vector collection.

Specified by:

performSignificanceTest in class SignificanceTestOperator

getProbability

private double getProbability(PerformanceCriterion pc1,
                              PerformanceCriterion pc2)

getMinSize

public int getMinSize()

Description copied from class: SignificanceTestOperator

Returns the minimum number of performance vectors which can be compared by this significance test.

Specified by:

getMinSize in class SignificanceTestOperator

getMaxSize

public int getMaxSize()

Description copied from class: SignificanceTestOperator

Returns the maximum number of performance vectors which can be compared by this significance test.

Specified by:

getMaxSize in class SignificanceTestOperator