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

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.SimpleCriterion

All Implemented Interfaces:

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

Direct Known Subclasses:

AbsoluteError, RelativeError, RootMeanSquaredError, SimpleAccuracy, SquaredError

public abstract class SimpleCriterion
extends MeasuredPerformance

Simple criteria are those which error can be counted for each example and can be averaged by the number of examples. The fitness has a reciprocal value of the error. Subclasses might also want to implement the method transform(double) which applies a transformation on the value sum divided by the number of counted examples. This is for example usefull in case of root_means_squared error. All subclasses can be used for both regression and classification problems. In case of classification the confidence value for the desired true label is used as prediction.

Version:

$Id: SimpleCriterion.java,v 2.25 2006/08/03 14:39:30 ingomierswa Exp $

Author:

Ingo Mierswa, Simon Fischer

Field Summary

private int	exampleCount
private Attribute	labelAttribute
private Attribute	predictedAttribute
private double	squaresSum
private double	sum

Constructor Summary

SimpleCriterion()

Method Summary

void	buildSingleAverage(Averagable performance) This method should build the average of this and another averagables of the same type.
protected void	cloneAveragable(Averagable newAvg) Must be implemented by subclasses such that it copies all values of other to this.
protected void	countExample(double deviation)
protected abstract double	countExample(double label, double predictedLabel) Subclasses must count the example and return the value to sum up.
void	countExample(Example example) Invokes countExample(double, double) and counts the deviation.
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.
void	readCriterionData(java.io.BufferedReader in) Reads the performance data from the given reader.
void	startCounting(ExampleSet eset) Initialises the criterion.
protected double	transform(double value) Simply returns the given value.
void	writeCriterionData(java.io.PrintWriter out) Writes the performance criterion into the given writer.

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

getDescription

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, getName, 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

predictedAttribute

private Attribute predictedAttribute

labelAttribute

private Attribute labelAttribute

sum

private double sum

squaresSum

private double squaresSum

exampleCount

private int exampleCount

Constructor Detail

SimpleCriterion

public SimpleCriterion()

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

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)

Invokes countExample(double, double) and counts the deviation. In case of a nominal label the confidence of the desired true label is used as prediction. For regression problems the usual predicted label is used.

Specified by:

countExample in class MeasuredPerformance

countExample

protected abstract double countExample(double label,
                                       double predictedLabel)

Subclasses must count the example and return the value to sum up.

transform

protected double transform(double value)

Simply returns the given value. Subclasses might apply a transformation on the error sum divided by the number of examples.

countExample

protected void countExample(double deviation)

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

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

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

cloneAveragable

protected void cloneAveragable(Averagable newAvg)

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 performance)

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