weka.classifiers.meta
Class Grading

java.lang.Object
  weka.classifiers.Classifier
      weka.classifiers.MultipleClassifiersCombiner
          weka.classifiers.RandomizableMultipleClassifiersCombiner
              weka.classifiers.meta.Stacking
                  weka.classifiers.meta.Grading

All Implemented Interfaces:

java.lang.Cloneable, OptionHandler, Randomizable, java.io.Serializable

public class Grading

extends Stacking

Implements Grading. For more information, see

Seewald A.K., Fuernkranz J. (2001): An Evaluation of Grading Classifiers, in Hoffmann F.\ et al.\ (eds.), Advances in Intelligent Data Analysis, 4th International Conference, IDA 2001, Proceedings, Springer, Berlin/Heidelberg/New York/Tokyo, pp.115-124, 2001 Valid options are:

-X num_folds
The number of folds for the cross-validation (default 10).

-S seed
Random number seed (default 1).

-B classifierstring
Classifierstring should contain the full class name of a base scheme followed by options to the classifier. (required, option should be used once for each classifier).

-M classifierstring
Classifierstring for the meta classifier. Same format as for base classifiers. This classifier estimates confidence in prediction of base classifiers. (required)

Version:

$Revision: 1.4 $

Author:

Alexander K. Seewald (alex@seewald.at), Eibe Frank (eibe@cs.waikato.ac.nz)

See Also:

Serialized Form

Field Summary

protected double[]	m_InstPerClass InstPerClass
protected Classifier[]	m_MetaClassifiers The meta classifiers, one for each base classifier.

Fields inherited from class weka.classifiers.meta.Stacking

m_BaseFormat, m_MetaClassifier, m_MetaFormat, m_NumFolds

Fields inherited from class weka.classifiers.RandomizableMultipleClassifiersCombiner

m_Seed

Fields inherited from class weka.classifiers.MultipleClassifiersCombiner

m_Classifiers

Fields inherited from class weka.classifiers.Classifier

m_Debug

Constructor Summary

Grading()

Method Summary

double[]	distributionForInstance(Instance instance) Returns class probabilities for a given instance using the stacked classifier.
protected void	generateMetaLevel(Instances newData, java.util.Random random) Generates the meta data
java.lang.String	globalInfo() Returns a string describing classifier
static void	main(java.lang.String[] argv) Main method for testing this class.
protected Instances	metaFormat(Instances instances) Makes the format for the level-1 data.
protected Instance	metaInstance(Instance instance, int k) Makes a level-1 instance from the given instance.
java.lang.String	toString() Output a representation of this classifier

Methods inherited from class weka.classifiers.meta.Stacking

buildClassifier, getMetaClassifier, getNumFolds, getOptions, listOptions, metaClassifierTipText, metaInstance, metaOption, numFoldsTipText, processMetaOptions, setMetaClassifier, setNumFolds, setOptions

Methods inherited from class weka.classifiers.RandomizableMultipleClassifiersCombiner

getSeed, seedTipText, setSeed

Methods inherited from class weka.classifiers.MultipleClassifiersCombiner

classifiersTipText, getClassifier, getClassifiers, getClassifierSpec, setClassifiers

Methods inherited from class weka.classifiers.Classifier

classifyInstance, debugTipText, forName, getDebug, makeCopies, setDebug

Methods inherited from class java.lang.Object

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

Field Detail

m_MetaClassifiers

protected Classifier[] m_MetaClassifiers

The meta classifiers, one for each base classifier.

m_InstPerClass

protected double[] m_InstPerClass

InstPerClass

Constructor Detail

Grading

public Grading()

Method Detail

globalInfo

public java.lang.String globalInfo()

Returns a string describing classifier

Overrides:

globalInfo in class Stacking

Returns:

a description suitable for displaying in the explorer/experimenter gui

generateMetaLevel

protected void generateMetaLevel(Instances newData,
                                 java.util.Random random)
                          throws java.lang.Exception

Generates the meta data

Overrides:

generateMetaLevel in class Stacking

Throws:

java.lang.Exception

distributionForInstance

public double[] distributionForInstance(Instance instance)
                                 throws java.lang.Exception

Returns class probabilities for a given instance using the stacked classifier. One class will always get all the probability mass (i.e. probability one).

Overrides:

distributionForInstance in class Stacking

Parameters:

instance - the instance to be classified

Throws:

java.lang.Exception - if instance could not be classified successfully

toString

public java.lang.String toString()

Output a representation of this classifier

Overrides:

toString in class Stacking

metaFormat

protected Instances metaFormat(Instances instances)
                        throws java.lang.Exception

Makes the format for the level-1 data.

Overrides:

metaFormat in class Stacking

Parameters:

instances - the level-0 format

Returns:

the format for the meta data

Throws:

java.lang.Exception

metaInstance

protected Instance metaInstance(Instance instance,
                                int k)
                         throws java.lang.Exception

Makes a level-1 instance from the given instance.

Parameters:

instance - the instance to be transformed

Returns:

the level-1 instance

Throws:

java.lang.Exception

main

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

Main method for testing this class.

Parameters:

argv - should contain the following arguments: -t training file [-T test file] [-c class index]