edu.udo.cs.yale.operator.validation
Class XValidation

java.lang.Object
  edu.udo.cs.yale.operator.Operator
      edu.udo.cs.yale.operator.OperatorChain
          edu.udo.cs.yale.operator.validation.ValidationChain
              edu.udo.cs.yale.operator.validation.XValidation

All Implemented Interfaces:

ConfigurationListener

public class XValidation
extends ValidationChain

XValidation encapsulates a cross-validation experiment. The example set S is split up into number_of_validations subsets S_i. The inner operators are applied number_of_validations times using S_i as the test set (input of the second inner operator) and S\backslash S_i training set (input of the first inner operator).

The first inner operator must accept an ExampleSet while the second must accept an ExampleSet and the output of the first (which is in most cases a Model) and must produce a PerformanceVector.

Like other validation schemes the Yale cross validation can use several types of sampling for building the subsets. Linear sampling simply divides the example set into partitions without changing the order of the examples. Shuffled sampling build random subsets from the data. Stratifed sampling builds random subsets and ensures that the class distribution in the subsets is the same as in the whole example set.

Version:

$Id: XValidation.java,v 1.25 2006/09/29 21:09:36 ingomierswa Exp $

Author:

Ingo Mierswa

Keywords:

cross-validation

Field Summary

private int	iteration
private int	number

Constructor Summary

XValidation(OperatorDescription description)

Method Summary

IOObject[]	estimatePerformance(ExampleSet inputSet) This is the main method of the validation chain and must be implemented to estimate a performance of inner operators on the given example set.
int	getNumberOfValidationSteps() Returns the number of validation steps, i.e. the number of times the inner operators of this validation chain are performed.
java.util.List<ParameterType>	getParameterTypes() Returns a list of ParameterTypes describing the parameters of this operator.

Methods inherited from class edu.udo.cs.yale.operator.validation.ValidationChain

apply, evaluate, getInnerOperatorCondition, getInputClasses, getInputDescription, getMaxNumberOfInnerOperators, getMinNumberOfInnerOperators, getNumberOfSteps, getOutputClasses, learn, setResult

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

addAddListener, addOperator, addOperator, checkDeprecations, checkIO, checkNumberOfInnerOperators, checkProperties, clearErrorList, clearStepCounter, cloneOperator, countStep, createExperimentTree, delete, experimentFinished, experimentStarts, getAllInnerOperators, getCurrentStep, getIndexOfOperator, getInnerOperatorForName, getInnerOperatorsXML, getNumberOfAllOperators, getNumberOfChildrensSteps, getNumberOfOperators, getOperator, getOperatorFromAll, getOperators, isEnabled, performAdditionalChecks, removeAddListener, removeOperator, setEnabled, setExperiment, shouldReturnInnerOutput

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

addError, addValue, addWarning, apply, createExperimentTree, createFromXML, createMarkedExperimentTree, getAddOnlyAdditionalOutput, getApplyCount, getDeliveredOutputClasses, getDeprecationInfo, getDesiredInputClasses, getErrorList, getExperiment, getInput, getInput, getInput, getIOContainerForInApplyLoopBreakpoint, getName, getOperatorClassName, getOperatorDescription, getParameter, getParameterAsBoolean, getParameterAsColor, getParameterAsDouble, getParameterAsFile, getParameterAsInt, getParameterAsString, getParameterList, getParameters, getParameterType, getParent, getStartTime, getStatus, getUserDescription, getValue, getValues, getXML, hasBreakpoint, hasBreakpoint, hasInput, inApplyLoop, isParameterSet, logMessage, register, remove, rename, resume, setBreakpoint, 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

Field Detail

number

private int number

iteration

private int iteration

Constructor Detail

XValidation

public XValidation(OperatorDescription description)

Method Detail

getNumberOfValidationSteps

public int getNumberOfValidationSteps()

Description copied from class: ValidationChain

Returns the number of validation steps, i.e. the number of times the inner operators of this validation chain are performed. For example this method should returns the number of iterations in case of a crossvalidation.

Specified by:

getNumberOfValidationSteps in class ValidationChain

estimatePerformance

public IOObject[] estimatePerformance(ExampleSet inputSet)
                               throws OperatorException

Description copied from class: ValidationChain

This is the main method of the validation chain and must be implemented to estimate a performance of inner operators on the given example set. The implementation can make use of the provided helper methods in this class.

Specified by:

estimatePerformance in class ValidationChain

Throws:

OperatorException

getParameterTypes

public java.util.List<ParameterType> getParameterTypes()

Description copied from class: Operator

Returns a list of ParameterTypes describing the parameters of this operator. The default implementation returns an empty list if no input objects can be retained and special parameters for those input objects which can be prevented from being consumed.

Overrides:

getParameterTypes in class ValidationChain