weka.attributeSelection
Class SymmetricalUncertAttributeSetEval

java.lang.Object
  extended by weka.attributeSelection.ASEvaluation
      extended by weka.attributeSelection.AttributeSetEvaluator
          extended by weka.attributeSelection.SymmetricalUncertAttributeSetEval
All Implemented Interfaces:
java.io.Serializable, CapabilitiesHandler, OptionHandler, RevisionHandler, TechnicalInformationHandler

public class SymmetricalUncertAttributeSetEval
extends AttributeSetEvaluator
implements OptionHandler, TechnicalInformationHandler

SymmetricalUncertAttributeSetEval :

Evaluates the worth of a set attributes by measuring the symmetrical uncertainty with respect to another set of attributes.

SymmU(AttributeSet2, AttributeSet1) = 2 * (H(AttributeSet2) - H(AttributeSet1 | AttributeSet2)) / H(AttributeSet2) + H(AttributeSet1).

For more information see:

Lei Yu, Huan Liu: Feature Selection for High-Dimensional Data: A Fast Correlation-Based Filter Solution. In: Proceedings of the Twentieth International Conference on Machine Learning, 856-863, 2003.

BibTeX:

 @inproceedings{Yu2003,
    author = {Lei Yu and Huan Liu},
    booktitle = {Proceedings of the Twentieth International Conference on Machine Learning},
    pages = {856-863},
    publisher = {AAAI Press},
    title = {Feature Selection for High-Dimensional Data: A Fast Correlation-Based Filter Solution},
    year = {2003}
 }
 

Valid options are:

 -M
  treat missing values as a seperate value.

Version:
$Revision: 5511 $
Author:
Zheng Zhao: zhaozheng at asu.edu
See Also:
Discretize, Serialized Form

Constructor Summary
SymmetricalUncertAttributeSetEval()
          Constructor
 
Method Summary
 void buildEvaluator(Instances data)
          Initializes a symmetrical uncertainty attribute evaluator.
 double evaluateAttribute(int attribute)
          evaluates an individual attribute by measuring the symmetrical uncertainty between it and the class.
 double evaluateAttribute(int[] attributes, int[] classAttributes)
          calculate symmetrical uncertainty between sets of attributes
 Capabilities getCapabilities()
          Returns the capabilities of this evaluator.
 boolean getMissingMerge()
          get whether missing values are being distributed or not
 java.lang.String[] getOptions()
          Gets the current settings of WrapperSubsetEval.
 java.lang.String getRevision()
          Returns the revision string.
 TechnicalInformation getTechnicalInformation()
          Returns an instance of a TechnicalInformation object, containing detailed information about the technical background of this class, e.g., paper reference or book this class is based on.
 java.lang.String globalInfo()
          Returns a string describing this attribute evaluator
 java.util.Enumeration listOptions()
          Returns an enumeration describing the available options.
static void main(java.lang.String[] argv)
          Main method for testing this class.
 java.lang.String missingMergeTipText()
          Returns the tip text for this property
 void setMissingMerge(boolean b)
          distribute the counts for missing values across observed values
 void setOptions(java.lang.String[] options)
          Parses a given list of options.
 java.lang.String toString()
          Return a description of the evaluator
 
Methods inherited from class weka.attributeSelection.ASEvaluation
forName, makeCopies, postProcess
 
Methods inherited from class java.lang.Object
equals, getClass, hashCode, notify, notifyAll, wait, wait, wait
 

Constructor Detail

SymmetricalUncertAttributeSetEval

public SymmetricalUncertAttributeSetEval()
Constructor

Method Detail

globalInfo

public java.lang.String globalInfo()
Returns a string describing this attribute evaluator

Returns:
a description of the evaluator suitable for displaying in the explorer/experimenter gui

getTechnicalInformation

public TechnicalInformation getTechnicalInformation()
Returns an instance of a TechnicalInformation object, containing detailed information about the technical background of this class, e.g., paper reference or book this class is based on.

Specified by:
getTechnicalInformation in interface TechnicalInformationHandler
Returns:
the technical information about this class

listOptions

public java.util.Enumeration listOptions()
Returns an enumeration describing the available options.

Specified by:
listOptions in interface OptionHandler
Returns:
an enumeration of all the available options.

setOptions

public void setOptions(java.lang.String[] options)
                throws java.lang.Exception
Parses a given list of options.

Valid options are:

 -M
  treat missing values as a seperate value.

Specified by:
setOptions in interface OptionHandler
Parameters:
options - the list of options as an array of strings
Throws:
java.lang.Exception - if an option is not supported

missingMergeTipText

public java.lang.String missingMergeTipText()
Returns the tip text for this property

Returns:
tip text for this property suitable for displaying in the explorer/experimenter gui

setMissingMerge

public void setMissingMerge(boolean b)
distribute the counts for missing values across observed values

Parameters:
b - true=distribute missing values.

getMissingMerge

public boolean getMissingMerge()
get whether missing values are being distributed or not

Returns:
true if missing values are being distributed.

getOptions

public java.lang.String[] getOptions()
Gets the current settings of WrapperSubsetEval.

Specified by:
getOptions in interface OptionHandler
Returns:
an array of strings suitable for passing to setOptions()

getCapabilities

public Capabilities getCapabilities()
Returns the capabilities of this evaluator.

Specified by:
getCapabilities in interface CapabilitiesHandler
Overrides:
getCapabilities in class ASEvaluation
Returns:
the capabilities of this evaluator
See Also:
Capabilities

buildEvaluator

public void buildEvaluator(Instances data)
                    throws java.lang.Exception
Initializes a symmetrical uncertainty attribute evaluator. Discretizes all attributes that are numeric.

Specified by:
buildEvaluator in class ASEvaluation
Parameters:
data - set of instances serving as training data
Throws:
java.lang.Exception - if the evaluator has not been generated successfully

evaluateAttribute

public double evaluateAttribute(int attribute)
                         throws java.lang.Exception
evaluates an individual attribute by measuring the symmetrical uncertainty between it and the class.

Specified by:
evaluateAttribute in class AttributeSetEvaluator
Parameters:
attribute - the index of the attribute to be evaluated
Returns:
the uncertainty
Throws:
java.lang.Exception - if the attribute could not be evaluated

evaluateAttribute

public double evaluateAttribute(int[] attributes,
                                int[] classAttributes)
                         throws java.lang.Exception
calculate symmetrical uncertainty between sets of attributes

Specified by:
evaluateAttribute in class AttributeSetEvaluator
Parameters:
attributes - the indexes of the attributes
classAttributes - the indexes of the attributes whose combination will be used as class label
Returns:
the uncertainty
Throws:
java.lang.Exception - if the attribute could not be evaluated

toString

public java.lang.String toString()
Return a description of the evaluator

Overrides:
toString in class java.lang.Object
Returns:
description as a string

getRevision

public java.lang.String getRevision()
Returns the revision string.

Specified by:
getRevision in interface RevisionHandler
Overrides:
getRevision in class ASEvaluation
Returns:
the revision

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