weka.classifiers

## Class BVDecomposeSegCVSub

- java.lang.Object
- - weka.classifiers.BVDecomposeSegCVSub

- All Implemented Interfaces:
    OptionHandler, RevisionHandler, TechnicalInformationHandler

      public class BVDecomposeSegCVSub
      extends java.lang.Object
      implements OptionHandler, TechnicalInformationHandler, RevisionHandler

  This class performs Bias-Variance decomposion on any classifier using the sub-sampled cross-validation procedure as specified in (1).
  The Kohavi and Wolpert definition of bias and variance is specified in (2).
  The Webb definition of bias and variance is specified in (3).
  Geoffrey I. Webb, Paul Conilione (2002). Estimating bias and variance from data. School of Computer Science and Software Engineering, Victoria, Australia.
  Ron Kohavi, David H. Wolpert: Bias Plus Variance Decomposition for Zero-One Loss Functions. In: Machine Learning: Proceedings of the Thirteenth International Conference, 275-283, 1996.
  Geoffrey I. Webb (2000). MultiBoosting: A Technique for Combining Boosting and Wagging. Machine Learning. 40(2):159-196.

  BibTeX:

       @misc{Webb2002,
          address = {School of Computer Science and Software Engineering, Victoria, Australia},
          author = {Geoffrey I. Webb and Paul Conilione},
          institution = {Monash University},
          title = {Estimating bias and variance from data},
          year = {2002},
          PDF = {http://www.csse.monash.edu.au/\~webb/Files/WebbConilione04.pdf}
       }

       @inproceedings{Kohavi1996,
          author = {Ron Kohavi and David H. Wolpert},
          booktitle = {Machine Learning: Proceedings of the Thirteenth International Conference},
          editor = {Lorenza Saitta},
          pages = {275-283},
          publisher = {Morgan Kaufmann},
          title = {Bias Plus Variance Decomposition for Zero-One Loss Functions},
          year = {1996},
          PS = {http://robotics.stanford.edu/\~ronnyk/biasVar.ps}
       }

       @article{Webb2000,
          author = {Geoffrey I. Webb},
          journal = {Machine Learning},
          number = {2},
          pages = {159-196},
          title = {MultiBoosting: A Technique for Combining Boosting and Wagging},
          volume = {40},
          year = {2000}
       }

  Valid options are:

       -c <class index>
        The index of the class attribute.
        (default last)

       -D
        Turn on debugging output.

       -l <num>
        The number of times each instance is classified.
        (default 10)

       -p <proportion of objects in common>
        The average proportion of instances common between any two training sets

       -s <seed>
        The random number seed used.

       -t <name of arff file>
        The name of the arff file used for the decomposition.

       -T <number of instances in training set>
        The number of instances in the training set.

       -W <classifier class name>
        Full class name of the learner used in the decomposition.
        eg: weka.classifiers.bayes.NaiveBayes

       Options specific to learner weka.classifiers.rules.ZeroR:

       -D
        If set, classifier is run in debug mode and
        may output additional info to the console

  Options after -- are passed to the designated sub-learner.

  Version:
    $Revision: 10141 $
  Author:
    Paul Conilione (paulc4321@yahoo.com.au)

- - ### Constructor Summary

    Constructors
    Constructor and Description
    `BVDecomposeSegCVSub()`

  - ### Method Summary

    Methods
    Modifier and Type | Method and Description
    --- | ---
    `void` | `decompose()` Carry out the bias-variance decomposition using the sub-sampled cross-validation method.
    `java.util.Vector<java.lang.Integer>` | `findCentralTendencies(double[] predProbs)` Finds the central tendency, given the classifications for an instance.
    `Classifier` | `getClassifier()` Gets the name of the classifier being analysed
    `int` | `getClassifyIterations()` Gets the number of times an instance is classified
    `int` | `getClassIndex()` Get the index (starting from 1) of the attribute used as the class.
    `java.lang.String` | `getDataFileName()` Get the name of the data file used for the decomposition
    `boolean` | `getDebug()` Gets whether debugging is turned on
    `double` | `getError()` Get the calculated error rate
    `double` | `getKWBias()` Get the calculated bias squared according to the Kohavi and Wolpert definition
    `double` | `getKWSigma()` Get the calculated sigma according to the Kohavi and Wolpert definition
    `double` | `getKWVariance()` Get the calculated variance according to the Kohavi and Wolpert definition
    `java.lang.String[]` | `getOptions()` Gets the current settings of the CheckClassifier.
    `double` | `getP()` Get the proportion of instances that are common between two training sets.
    `java.lang.String` | `getRevision()` Returns the revision string.
    `int` | `getSeed()` Gets the random number seed
    `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.
    `int` | `getTrainSize()` Get the training size
    `double` | `getWBias()` Get the calculated bias according to the Webb definition
    `double` | `getWVariance()` Get the calculated variance according to the Webb definition
    `java.lang.String` | `globalInfo()` Returns a string describing this object
    `java.util.Enumeration<Option>` | `listOptions()` Returns an enumeration describing the available options.
    `static void` | `main(java.lang.String[] args)` Test method for this class
    `void` | `randomize(int[] index, java.util.Random random)` Accepts an array of ints and randomises the values in the array, using the random seed.
    `void` | `setClassifier(Classifier newClassifier)` Set the classifiers being analysed
    `void` | `setClassifyIterations(int classifyIterations)` Sets the number of times an instance is classified
    `void` | `setClassIndex(int classIndex)` Sets index of attribute to discretize on
    `void` | `setDataFileName(java.lang.String dataFileName)` Sets the name of the dataset file.
    `void` | `setDebug(boolean debug)` Sets debugging mode
    `void` | `setOptions(java.lang.String[] options)` Sets the OptionHandler's options using the given list.
    `void` | `setP(double proportion)` Set the proportion of instances that are common between two training sets used to train a classifier.
    `void` | `setSeed(int seed)` Sets the random number seed
    `void` | `setTrainSize(int size)` Set the training size.
    `java.lang.String` | `toString()` Returns description of the bias-variance decomposition results.

    - ### Methods inherited from class java.lang.Object

      `equals, getClass, hashCode, notify, notifyAll, wait, wait, wait`

- - ### Constructor Detail

    - #### BVDecomposeSegCVSub

          public BVDecomposeSegCVSub()

  - ### Method Detail

    - #### globalInfo

          public java.lang.String globalInfo()

      Returns a string describing this object
      Returns:
        a description of the classifier 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<Option> 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

      Sets the OptionHandler's options using the given list. All options will be set (or reset) during this call (i.e. incremental setting of options is not possible).

      Valid options are:

           -c <class index>
            The index of the class attribute.
            (default last)

           -D
            Turn on debugging output.

           -l <num>
            The number of times each instance is classified.
            (default 10)

           -p <proportion of objects in common>
            The average proportion of instances common between any two training sets

           -s <seed>
            The random number seed used.

           -t <name of arff file>
            The name of the arff file used for the decomposition.

           -T <number of instances in training set>
            The number of instances in the training set.

           -W <classifier class name>
            Full class name of the learner used in the decomposition.
            eg: weka.classifiers.bayes.NaiveBayes

           Options specific to learner weka.classifiers.rules.ZeroR:

           -D
            If set, classifier is run in debug mode and
            may output additional info to the console

      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

    - #### getOptions

          public java.lang.String[] getOptions()

      Gets the current settings of the CheckClassifier.
      Specified by:
        `getOptions` in interface `OptionHandler`
      Returns:
        an array of strings suitable for passing to setOptions

    - #### setClassifier

          public void setClassifier(Classifier newClassifier)

      Set the classifiers being analysed
      Parameters:
        `newClassifier` - the Classifier to use.

    - #### getClassifier

          public Classifier getClassifier()

      Gets the name of the classifier being analysed
      Returns:
        the classifier being analysed.

    - #### setDebug

          public void setDebug(boolean debug)

      Sets debugging mode
      Parameters:
        `debug` - true if debug output should be printed

    - #### getDebug

          public boolean getDebug()

      Gets whether debugging is turned on
      Returns:
        true if debugging output is on

    - #### setSeed

          public void setSeed(int seed)

      Sets the random number seed
      Parameters:
        `seed` - the random number seed

    - #### getSeed

          public int getSeed()

      Gets the random number seed
      Returns:
        the random number seed

    - #### setClassifyIterations

          public void setClassifyIterations(int classifyIterations)

      Sets the number of times an instance is classified
      Parameters:
        `classifyIterations` - number of times an instance is classified

    - #### getClassifyIterations

          public int getClassifyIterations()

      Gets the number of times an instance is classified
      Returns:
        the maximum number of times an instance is classified

    - #### setDataFileName

          public void setDataFileName(java.lang.String dataFileName)

      Sets the name of the dataset file.
      Parameters:
        `dataFileName` - name of dataset file.

    - #### getDataFileName

          public java.lang.String getDataFileName()

      Get the name of the data file used for the decomposition
      Returns:
        the name of the data file

    - #### getClassIndex

          public int getClassIndex()

      Get the index (starting from 1) of the attribute used as the class.
      Returns:
        the index of the class attribute

    - #### setClassIndex

          public void setClassIndex(int classIndex)

      Sets index of attribute to discretize on
      Parameters:
        `classIndex` - the index (starting from 1) of the class attribute

    - #### getKWBias

          public double getKWBias()

      Get the calculated bias squared according to the Kohavi and Wolpert definition
      Returns:
        the bias squared

    - #### getWBias

          public double getWBias()

      Get the calculated bias according to the Webb definition
      Returns:
        the bias

    - #### getKWVariance

          public double getKWVariance()

      Get the calculated variance according to the Kohavi and Wolpert definition
      Returns:
        the variance

    - #### getWVariance

          public double getWVariance()

      Get the calculated variance according to the Webb definition
      Returns:
        the variance according to Webb

    - #### getKWSigma

          public double getKWSigma()

      Get the calculated sigma according to the Kohavi and Wolpert definition
      Returns:
        the sigma

    - #### setTrainSize

          public void setTrainSize(int size)

      Set the training size.
      Parameters:
        `size` - the size of the training set

    - #### getTrainSize

          public int getTrainSize()

      Get the training size
      Returns:
        the size of the training set

    - #### setP

          public void setP(double proportion)

      Set the proportion of instances that are common between two training sets used to train a classifier.
      Parameters:
        `proportion` - the proportion of instances that are common between training sets.

    - #### getP

          public double getP()

      Get the proportion of instances that are common between two training sets.
      Returns:
        the proportion

    - #### getError

          public double getError()

      Get the calculated error rate
      Returns:
        the error rate

    - #### decompose

          public void decompose()
                         throws java.lang.Exception

      Carry out the bias-variance decomposition using the sub-sampled cross-validation method.
      Throws:
        `java.lang.Exception` - if the decomposition couldn't be carried out

    - #### findCentralTendencies

          public java.util.Vector<java.lang.Integer> findCentralTendencies(double[] predProbs)

      Finds the central tendency, given the classifications for an instance. Where the central tendency is defined as the class that was most commonly selected for a given instance.

      For example, instance 'x' may be classified out of 3 classes y = {1, 2, 3}, so if x is classified 10 times, and is classified as follows, '1' = 2 times, '2' = 5 times and '3' = 3 times. Then the central tendency is '2'.

      However, it is important to note that this method returns a list of all classes that have the highest number of classifications. In cases where there are several classes with the largest number of classifications, then all of these classes are returned. For example if 'x' is classified '1' = 4 times, '2' = 4 times and '3' = 2 times. Then '1' and '2' are returned.

      Parameters:
        `predProbs` - the array of classifications for a single instance.
      Returns:
        a Vector containing Integer objects which store the class(s) which are the central tendency.

    - #### toString

          public java.lang.String toString()

      Returns description of the bias-variance decomposition results.
      Overrides:
        `toString` in class `java.lang.Object`
      Returns:
        the bias-variance decomposition results as a string

    - #### getRevision

          public java.lang.String getRevision()

      Returns the revision string.
      Specified by:
        `getRevision` in interface `RevisionHandler`
      Returns:
        the revision

    - #### main

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

      Test method for this class
      Parameters:
        `args` - the command line arguments

    - #### randomize

          public final void randomize(int[] index,
                       java.util.Random random)

      Accepts an array of ints and randomises the values in the array, using the random seed.
      Parameters:
        `index` - is the array of integers
        `random` - is the Random seed.