weka.classifiers.trees.j48

Class EntropyBasedSplitCrit

java.lang.Object

weka.classifiers.trees.j48.SplitCriterion

weka.classifiers.trees.j48.EntropyBasedSplitCrit

All Implemented Interfaces:

Serializable, RevisionHandler

Direct Known Subclasses:

EntropySplitCrit, GainRatioSplitCrit, InfoGainSplitCrit

public abstract class EntropyBasedSplitCrit
extends SplitCriterion

"Abstract" class for computing splitting criteria based on the entropy of a class distribution.

Version:

$Revision: 1.8 $

Author:

Eibe Frank (eibe@cs.waikato.ac.nz)

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
protected static double	log2 The log of 2.

Constructor Summary

Constructors

Constructor and Description
EntropyBasedSplitCrit()

Method Summary

Modifier and Type	Method and Description
double	logFunc(double num) Help method for computing entropy.
double	newEnt(Distribution bags) Computes entropy of distribution after splitting.
double	oldEnt(Distribution bags) Computes entropy of distribution before splitting.
double	splitEnt(Distribution bags) Computes entropy after splitting without considering the class values.

Methods inherited from class weka.classifiers.trees.j48.SplitCriterion

splitCritValue, splitCritValue, splitCritValue, splitCritValue

Methods inherited from class java.lang.Object

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

Methods inherited from interface weka.core.RevisionHandler

getRevision

Field Detail

log2

protected static double log2

The log of 2.

Constructor Detail

EntropyBasedSplitCrit

public EntropyBasedSplitCrit()

Method Detail

logFunc

public final double logFunc(double num)

Help method for computing entropy.

oldEnt

public final double oldEnt(Distribution bags)

Computes entropy of distribution before splitting.

newEnt

public final double newEnt(Distribution bags)

Computes entropy of distribution after splitting.

splitEnt

public final double splitEnt(Distribution bags)

Computes entropy after splitting without considering the class values.