edu.cmu.minorthird.classify.algorithms.linear
Class BalancedWinnow

java.lang.Object
  edu.cmu.minorthird.classify.OnlineClassifierLearner
      edu.cmu.minorthird.classify.OnlineBinaryClassifierLearner
          edu.cmu.minorthird.classify.algorithms.linear.BalancedWinnow

All Implemented Interfaces:

BinaryClassifierLearner, ClassifierLearner, java.io.Serializable, java.lang.Cloneable

public class BalancedWinnow
extends OnlineBinaryClassifierLearner
implements java.io.Serializable

Created on Sep 22, 2005

Author:

Vitor R. Carvalho Balanced Winnow algorithm as described in "Learning Quickly when Irrelevant Attributes Abound: a new linear-threshold algorithm", N. Littlestone, Machine Learning, 1988. Notation and some implementation details from "Mistake-Driven Learning in Text Categorization", I. Dagan, Y. Karov, D. Roth, EMNLP, 1997 Additionally, it implements 2 optional features: (a) update when examples don't satisfy a margin requirement (margin parameter) (b) optionally, classify with a voting scheme. (voted parameter)

See Also:

Serialized Form

Nested Class Summary

class

BalancedWinnow.MyClassifier

Constructor Summary

BalancedWinnow()

BalancedWinnow(boolean voted)
Constructor: voted="true" (more stable) or "false"(more aggressive)

BalancedWinnow(double a, double b, boolean voted)

Method Summary

void	addExample(Example example2) Subclasses should use this method to perform whatever incremental update is needed after in response to a new example.
Classifier	getClassifier() Subclasses should use this method to return the current classifier.
double	localscore(Instance ins)
static void	main(java.lang.String[] args)
void	reset() 'forget' everything about the last learning task, and start a new task.
java.lang.String	toString()
void	updateVotedHyperplane(double count)

Methods inherited from class edu.cmu.minorthird.classify.OnlineBinaryClassifierLearner

getBinaryClassifier, getSchema, setSchema

Methods inherited from class edu.cmu.minorthird.classify.OnlineClassifierLearner

completeTraining, copy, hasNextQuery, nextQuery, setInstancePool

Methods inherited from class java.lang.Object

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

Methods inherited from interface edu.cmu.minorthird.classify.ClassifierLearner

completeTraining, copy, hasNextQuery, nextQuery, setInstancePool

Constructor Detail

BalancedWinnow

public BalancedWinnow()

BalancedWinnow

public BalancedWinnow(boolean voted)

Constructor: voted="true" (more stable) or "false"(more aggressive)

Parameters:

voted -

BalancedWinnow

public BalancedWinnow(double a,
                      double b,
                      boolean voted)

Method Detail

reset

public void reset()

Description copied from class: OnlineClassifierLearner

'forget' everything about the last learning task, and start a new task. Subclasses need to implement this method

Specified by:

reset in interface ClassifierLearner

Specified by:

reset in class OnlineClassifierLearner

addExample

public void addExample(Example example2)

Description copied from class: OnlineClassifierLearner

Subclasses should use this method to perform whatever incremental update is needed after in response to a new example.

Specified by:

addExample in interface ClassifierLearner

Specified by:

addExample in class OnlineClassifierLearner

updateVotedHyperplane

public void updateVotedHyperplane(double count)

getClassifier

public Classifier getClassifier()

Description copied from class: OnlineClassifierLearner

Subclasses should use this method to return the current classifier.

Specified by:

getClassifier in interface ClassifierLearner

Specified by:

getClassifier in class OnlineClassifierLearner

localscore

public double localscore(Instance ins)

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

main

public static void main(java.lang.String[] args)