edu.udo.cs.yale.operator.performance
Class MDLCriterion

java.lang.Object
  edu.udo.cs.yale.operator.AbstractIOObject
      edu.udo.cs.yale.operator.ResultObjectAdapter
          edu.udo.cs.yale.tools.math.Averagable
              edu.udo.cs.yale.operator.performance.PerformanceCriterion
                  edu.udo.cs.yale.operator.performance.MeasuredPerformance
                      edu.udo.cs.yale.operator.performance.MDLCriterion

All Implemented Interfaces:

IOObject, ResultObject, java.lang.Cloneable, java.lang.Comparable<Averagable>

public class MDLCriterion
extends MeasuredPerformance

Measures the length of an example set (i.e. the number of attributes).

Version:

$Id: MDLCriterion.java,v 2.18 2006/08/03 14:39:30 ingomierswa Exp $

Author:

Ingo Mierswa

Field Summary

private int	counter A counter for average building.
private int	direction Indicates if the fitness should be higher or smaller depending on the number of features.
static java.lang.String[]	DIRECTIONS The possible optimization directions.
private int	length The length of this example set.
static int	MAXIMIZATION Indicates that the fitness should be higher for larger numbers of features.
static int	MINIMIZATION Indicates that the fitness should be higher for smaller numbers of features.

Constructor Summary

MDLCriterion()

MDLCriterion(int direction)

Method Summary

void	buildSingleAverage(Averagable averagable) This method should build the average of this and another averagables of the same type.
void	cloneAveragable(Averagable other) Must be implemented by subclasses such that it copies all values of other to this.
void	countExample(Example example) Counts a single example, e.g. by summing up errors.
java.lang.String	getDescription() Returns a description of the performance criterion.
int	getExampleCount() Returns the number of data points which was used to determine the criterion value.
double	getFitness() Returns the fitness depending on the value.
double	getMikroAverage() Returns the (current) value of the averagable (the average itself).
double	getMikroVariance() Returns the variance of the averagable.
java.lang.String	getName() Returns the name of this averagable.
void	readCriterionData(java.io.BufferedReader in) Reads the performance data from the given reader.
void	startCounting(ExampleSet eSet) Initialises the criterion.
void	writeCriterionData(java.io.PrintWriter out) Writes the performance criterion into the given writer.

Methods inherited from class edu.udo.cs.yale.operator.performance.PerformanceCriterion

compareTo, getMaxFitness, readPerformanceCriterion, writePerformanceCriterion

Methods inherited from class edu.udo.cs.yale.tools.math.Averagable

buildAverage, clone, formatDeviation, formatPercent, formatValue, getAverage, getMakroAverage, getMakroStandardDeviation, getMakroVariance, getMikroStandardDeviation, getStandardDeviation, getVariance, toHTML, toString

Methods inherited from class edu.udo.cs.yale.operator.ResultObjectAdapter

addAction, getActions, getVisualisationComponent, toHTML, toResultString

Methods inherited from class edu.udo.cs.yale.operator.AbstractIOObject

copy, read, read, read, write, write

Methods inherited from class java.lang.Object

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

Methods inherited from interface edu.udo.cs.yale.operator.IOObject

copy, write, write

Field Detail

DIRECTIONS

public static final java.lang.String[] DIRECTIONS

The possible optimization directions.

MINIMIZATION

public static final int MINIMIZATION

Indicates that the fitness should be higher for smaller numbers of features.

See Also:

Constant Field Values

MAXIMIZATION

public static final int MAXIMIZATION

Indicates that the fitness should be higher for larger numbers of features.

See Also:

Constant Field Values

length

private int length

The length of this example set.

counter

private int counter

A counter for average building.

direction

private int direction

Indicates if the fitness should be higher or smaller depending on the number of features.

Constructor Detail

MDLCriterion

public MDLCriterion()

MDLCriterion

public MDLCriterion(int direction)

Method Detail

writeCriterionData

public void writeCriterionData(java.io.PrintWriter out)
                        throws java.io.IOException

Description copied from class: PerformanceCriterion

Writes the performance criterion into the given writer. Please note that the criterion must be written in a human readable format!

Specified by:

writeCriterionData in class PerformanceCriterion

Throws:

java.io.IOException

readCriterionData

public void readCriterionData(java.io.BufferedReader in)
                       throws java.io.IOException

Description copied from class: PerformanceCriterion

Reads the performance data from the given reader.

Specified by:

readCriterionData in class PerformanceCriterion

Throws:

java.io.IOException

getName

public java.lang.String getName()

Description copied from class: Averagable

Returns the name of this averagable.

Specified by:

getName in interface ResultObject

Specified by:

getName in class Averagable

getDescription

public java.lang.String getDescription()

Description copied from class: MeasuredPerformance

Returns a description of the performance criterion.

Specified by:

getDescription in class MeasuredPerformance

startCounting

public void startCounting(ExampleSet eSet)
                   throws OperatorException

Description copied from class: MeasuredPerformance

Initialises the criterion. The default implementation does nothing.

Overrides:

startCounting in class MeasuredPerformance

Throws:

OperatorException

getExampleCount

public int getExampleCount()

Description copied from class: PerformanceCriterion

Returns the number of data points which was used to determine the criterion value.

Specified by:

getExampleCount in class PerformanceCriterion

countExample

public void countExample(Example example)

Description copied from class: MeasuredPerformance

Counts a single example, e.g. by summing up errors.

Specified by:

countExample in class MeasuredPerformance

getFitness

public double getFitness()

Description copied from class: PerformanceCriterion

Returns the fitness depending on the value. Subclasses should use getAverage() instead of getValue() in this method since usually the makro average should be optmized instead of the mikro average. The mikro average should only be used in the (rare) cases where no makro average is available.

Specified by:

getFitness in class PerformanceCriterion

getMikroAverage

public double getMikroAverage()

Description copied from class: Averagable

Returns the (current) value of the averagable (the average itself).

Specified by:

getMikroAverage in class Averagable

getMikroVariance

public double getMikroVariance()

Description copied from class: Averagable

Returns the variance of the averagable. The returned value must not be negative. If the averagable does not define a variance this method should return Double.NaN.

Specified by:

getMikroVariance in class Averagable

cloneAveragable

public void cloneAveragable(Averagable other)

Description copied from class: Averagable

Must be implemented by subclasses such that it copies all values of other to this. When this method is called, it is guaranteed, that other is a subclass of the class of the object it is called on.

Specified by:

cloneAveragable in class Averagable

buildSingleAverage

public void buildSingleAverage(Averagable averagable)

Description copied from class: Averagable

This method should build the average of this and another averagables of the same type. The next invocation of getValue() should return the average of this and the given averagable. Please refer to SimpleCriterion for a simple implementation example.

Specified by:

buildSingleAverage in class Averagable