weka.classifiers.misc
Class VFI

java.lang.Object
  |
  +--weka.classifiers.Classifier
        |
        +--weka.classifiers.misc.VFI
All Implemented Interfaces:
java.lang.Cloneable, OptionHandler, java.io.Serializable, WeightedInstancesHandler

public class VFI
extends Classifier
implements OptionHandler, WeightedInstancesHandler

Class implementing the voting feature interval classifier. For numeric attributes, upper and lower boundaries (intervals) are constructed around each class. Discrete attributes have point intervals. Class counts are recorded for each interval on each feature. Classification is by voting. Missing values are ignored. Does not handle numeric class.

Have added a simple attribute weighting scheme. Higher weight is assigned to more confident intervals, where confidence is a function of entropy: weight (att_i) = (entropy of class distrib att_i / max uncertainty)^-bias.

Faster than NaiveBayes but slower than HyperPipes.

  Confidence: 0.01 (two tailed)

 Dataset                   (1) VFI '-B  | (2) Hyper (3) Naive
                         ------------------------------------
 anneal.ORIG               (10)   74.56 |   97.88 v   74.77
 anneal                    (10)   71.83 |   97.88 v   86.51 v
 audiology                 (10)   51.69 |   66.26 v   72.25 v
 autos                     (10)   57.63 |   62.79 v   57.76
 balance-scale             (10)   68.72 |   46.08 *   90.5  v
 breast-cancer             (10)   67.25 |   69.84 v   73.12 v
 wisconsin-breast-cancer   (10)   95.72 |   88.31 *   96.05 v
 horse-colic.ORIG          (10)   66.13 |   70.41 v   66.12
 horse-colic               (10)   78.36 |   62.07 *   78.28
 credit-rating             (10)   85.17 |   44.58 *   77.84 *
 german_credit             (10)   70.81 |   69.89 *   74.98 v
 pima_diabetes             (10)   62.13 |   65.47 v   75.73 v
 Glass                     (10)   56.82 |   50.19 *   47.43 *
 cleveland-14-heart-diseas (10)   80.01 |   55.18 *   83.83 v
 hungarian-14-heart-diseas (10)   82.8  |   65.55 *   84.37 v
 heart-statlog             (10)   79.37 |   55.56 *   84.37 v
 hepatitis                 (10)   83.78 |   63.73 *   83.87
 hypothyroid               (10)   92.64 |   93.33 v   95.29 v
 ionosphere                (10)   94.16 |   35.9  *   82.6  *
 iris                      (10)   96.2  |   91.47 *   95.27 *
 kr-vs-kp                  (10)   88.22 |   54.1  *   87.84 *
 labor                     (10)   86.73 |   87.67     93.93 v
 lymphography              (10)   78.48 |   58.18 *   83.24 v
 mushroom                  (10)   99.85 |   99.77 *   95.77 *
 primary-tumor             (10)   29    |   24.78 *   49.35 v
 segment                   (10)   77.42 |   75.15 *   80.1  v
 sick                      (10)   65.92 |   93.85 v   92.71 v
 sonar                     (10)   58.02 |   57.17     67.97 v
 soybean                   (10)   86.81 |   86.12 *   92.9  v
 splice                    (10)   88.61 |   41.97 *   95.41 v
 vehicle                   (10)   52.94 |   32.77 *   44.8  *
 vote                      (10)   91.5  |   61.38 *   90.19 *
 vowel                     (10)   57.56 |   36.34 *   62.81 v
 waveform                  (10)   56.33 |   46.11 *   80.02 v
 zoo                       (10)   94.05 |   94.26     95.04 v
                          ------------------------------------
                                (v| |*) |  (9|3|23)  (22|5|8) 
 

For more information, see

Demiroz, G. and Guvenir, A. (1997) "Classification by voting feature intervals", ECML-97.

Valid options are:

-C
Don't Weight voting intervals by confidence.

-B
Set exponential bias towards confident intervals. default = 1.0

Version:
$Revision: 1.9 $
Author:
Mark Hall (mhall@cs.waikato.ac.nz)
See Also:
Serialized Form

Constructor Summary
VFI()
           
 
Method Summary
 java.lang.String biasTipText()
          Returns the tip text for this property
 void buildClassifier(Instances instances)
          Generates the classifier.
 double[] distributionForInstance(Instance instance)
          Classifies the given test instance.
 double getBias()
          Get the value of the bias parameter
 java.lang.String[] getOptions()
          Gets the current settings of VFI
 boolean getWeightByConfidence()
          Get whether feature intervals are being weighted by confidence
 java.lang.String globalInfo()
          Returns a string describing this search method
 java.util.Enumeration listOptions()
          Returns an enumeration describing the available options.
static void main(java.lang.String[] args)
          Main method for testing this class.
 void setBias(double b)
          Set the value of the exponential bias towards more confident intervals
 void setOptions(java.lang.String[] options)
          Parses a given list of options.
 void setWeightByConfidence(boolean c)
          Set weighting by confidence
 java.lang.String toString()
          Returns a description of this classifier.
 java.lang.String weightByConfidenceTipText()
          Returns the tip text for this property
 
Methods inherited from class weka.classifiers.Classifier
classifyInstance, debugTipText, forName, getDebug, makeCopies, setDebug
 
Methods inherited from class java.lang.Object
equals, getClass, hashCode, notify, notifyAll, wait, wait, wait
 

Constructor Detail

VFI

public VFI()
Method Detail

globalInfo

public java.lang.String globalInfo()
Returns a string describing this search method

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

listOptions

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

Specified by:
listOptions in interface OptionHandler
Overrides:
listOptions in class Classifier
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:

-C
Don't weight voting intervals by confidence.

-B
Set exponential bias towards confident intervals. default = 1.0

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

weightByConfidenceTipText

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

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

setWeightByConfidence

public void setWeightByConfidence(boolean c)
Set weighting by confidence

Parameters:
c - true if feature intervals are to be weighted by confidence

getWeightByConfidence

public boolean getWeightByConfidence()
Get whether feature intervals are being weighted by confidence

Returns:
true if weighting by confidence is selected

biasTipText

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

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

setBias

public void setBias(double b)
Set the value of the exponential bias towards more confident intervals

Parameters:
b - the value of the bias parameter

getBias

public double getBias()
Get the value of the bias parameter

Returns:
the bias parameter

getOptions

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

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

buildClassifier

public void buildClassifier(Instances instances)
                     throws java.lang.Exception
Generates the classifier.

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

toString

public java.lang.String toString()
Returns a description of this classifier.

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

distributionForInstance

public double[] distributionForInstance(Instance instance)
                                 throws java.lang.Exception
Classifies the given test instance.

Overrides:
distributionForInstance in class Classifier
Parameters:
instance - the instance to be classified
Returns:
the predicted class for the instance
Throws:
java.lang.Exception - if the instance can't be classified

main

public static void main(java.lang.String[] args)
Main method for testing this class.

Parameters:
args - should contain command line arguments for evaluation (see Evaluation).


Copyright (c) 2003 David Lindsay, Computer Learning Research Centre, Dept. Computer Science, Royal Holloway, University of London