weka.attributeSelection
Class HoldOutSubsetEvaluator

java.lang.Object
  weka.attributeSelection.ASEvaluation
      weka.attributeSelection.HoldOutSubsetEvaluator

All Implemented Interfaces:

Serializable, SubsetEvaluator, CapabilitiesHandler, RevisionHandler

public abstract class HoldOutSubsetEvaluator
extends ASEvaluation
implements SubsetEvaluator

Abstract attribute subset evaluator capable of evaluating subsets with respect to a data set that is distinct from that used to initialize/ train the subset evaluator.

Version:

$Revision: 8034 $

Author:

Mark Hall (mhall@cs.waikato.ac.nz)

See Also:

Serialized Form

Constructor Summary

HoldOutSubsetEvaluator()

Method Summary

abstract double	evaluateSubset(BitSet subset, Instance holdOut, boolean retrain) Evaluates a subset of attributes with respect to a single instance.
abstract double	evaluateSubset(BitSet subset, Instances holdOut) Evaluates a subset of attributes with respect to a set of instances.

Methods inherited from class weka.attributeSelection.ASEvaluation

buildEvaluator, forName, getCapabilities, getRevision, makeCopies, postProcess, runEvaluator

Methods inherited from class java.lang.Object

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

Methods inherited from interface weka.attributeSelection.SubsetEvaluator

evaluateSubset

Constructor Detail

HoldOutSubsetEvaluator

public HoldOutSubsetEvaluator()

Method Detail

evaluateSubset

public abstract double evaluateSubset(BitSet subset,
                                      Instances holdOut)
                               throws Exception

Evaluates a subset of attributes with respect to a set of instances.

Parameters:

subset - a bitset representing the attribute subset to be evaluated

holdOut - a set of instances (possibly seperate and distinct from those use to build/train the evaluator) with which to evaluate the merit of the subset

Returns:

the "merit" of the subset on the holdOut data

Throws:

Exception - if the subset cannot be evaluated

evaluateSubset

public abstract double evaluateSubset(BitSet subset,
                                      Instance holdOut,
                                      boolean retrain)
                               throws Exception

Evaluates a subset of attributes with respect to a single instance.

Parameters:

subset - a bitset representing the attribute subset to be evaluated

holdOut - a single instance (possibly not one of those used to build/train the evaluator) with which to evaluate the merit of the subset

retrain - true if the classifier should be retrained with respect to the new subset before testing on the holdOut instance.

Returns:

the "merit" of the subset on the holdOut instance

Throws:

Exception - if the subset cannot be evaluated