de.jstacs.classifiers.performanceMeasures
Class PositivePredictiveValueForFixedSensitivity

java.lang.Object
  de.jstacs.parameters.ParameterSet
      de.jstacs.classifiers.performanceMeasures.AbstractPerformanceMeasure
          de.jstacs.classifiers.performanceMeasures.AbstractTwoClassPerformanceMeasure
              de.jstacs.classifiers.performanceMeasures.AbstractNumericalTwoClassPerformanceMeasure
                  de.jstacs.classifiers.performanceMeasures.PositivePredictiveValueForFixedSensitivity

All Implemented Interfaces:

NumericalPerformanceMeasure, PerformanceMeasure, GalaxyConvertible, Storable, Cloneable

public class PositivePredictiveValueForFixedSensitivity
extends AbstractNumericalTwoClassPerformanceMeasure

This class implements the positive predictive value for a fixed sensitivity. The positive predictive value is defined as and the sensitivity is defined as . The classification threshold for computing the positive predictive value is chosen such that the classifier yields at least the specified sensitivity. This measure corresponds to a specific point on the PRCurve.

Author:

Jan Grau, Jens Keilwagen

Nested Class Summary

Nested classes/interfaces inherited from class de.jstacs.parameters.ParameterSet

ParameterSet.ParameterList

Field Summary

Fields inherited from class de.jstacs.parameters.ParameterSet

errorMessage, parameters, parent

Constructor Summary

PositivePredictiveValueForFixedSensitivity()
Constructs a new instance of the performance measure PositivePredictiveValueForFixedSensitivity with empty parameter values.

PositivePredictiveValueForFixedSensitivity(double sensitivity)
Constructs a new instance of the performance measure PositivePredictiveValueForFixedSensitivity with given sensitivity.

PositivePredictiveValueForFixedSensitivity(StringBuffer xml)
The standard constructor for the interface Storable.

Method Summary

NumericalResultSet	compute(double[] sortedScoresClass0, double[] weightsClass0, double[] sortedScoresClass1, double[] weightsClass1) This method allows to compute the performance measure of given sorted score ratios.
String	getName() The method returns the name of the performance measure.

Methods inherited from class de.jstacs.classifiers.performanceMeasures.AbstractNumericalTwoClassPerformanceMeasure

compute, compute, compute

Methods inherited from class de.jstacs.classifiers.performanceMeasures.AbstractTwoClassPerformanceMeasure

getAllowedNumberOfClasses

Methods inherited from class de.jstacs.classifiers.performanceMeasures.AbstractPerformanceMeasure

findSplitIndex, findThreshold, getCollectionOfAllMeasures, getWeight, simpleWeights

Methods inherited from class de.jstacs.parameters.ParameterSet

clone, fromGalaxy, fromXML, getAllParameterNames, getComment, getComment, getErrorMessage, getIndex, getName, getName, getNumberOfParameters, getParameterAt, getParameterForName, getParent, hasDefaultOrIsSet, initParameterList, initParameterList, isAtomic, isComparable, parametersLoaded, reset, setParent, toGalaxy, toXML

Methods inherited from class java.lang.Object

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

Methods inherited from interface de.jstacs.classifiers.performanceMeasures.PerformanceMeasure

getAllowedNumberOfClasses

Constructor Detail

PositivePredictiveValueForFixedSensitivity

public PositivePredictiveValueForFixedSensitivity()

Constructs a new instance of the performance measure PositivePredictiveValueForFixedSensitivity with empty parameter values.

PositivePredictiveValueForFixedSensitivity

public PositivePredictiveValueForFixedSensitivity(double sensitivity)
                                           throws Exception

Constructs a new instance of the performance measure PositivePredictiveValueForFixedSensitivity with given sensitivity.

Parameters:

sensitivity - the sensitivity for which the positive predictive value should be computed

Throws:

Exception - if the internal parameters can not be created or the value can not be set

PositivePredictiveValueForFixedSensitivity

public PositivePredictiveValueForFixedSensitivity(StringBuffer xml)
                                           throws NonParsableException

The standard constructor for the interface Storable. Constructs a PositivePredictiveValueForFixedSensitivity out of an XML representation.

Parameters:

xml - the XML representation as StringBuffer

Throws:

NonParsableException - if the PositivePredictiveValueForFixedSensitivity could not be reconstructed out of the StringBuffer xml

Method Detail

getName

public String getName()

Description copied from interface: PerformanceMeasure

The method returns the name of the performance measure.

Specified by:

getName in interface PerformanceMeasure

Specified by:

getName in class AbstractPerformanceMeasure

Returns:

the name of the performance measure

compute

public NumericalResultSet compute(double[] sortedScoresClass0,
                                  double[] weightsClass0,
                                  double[] sortedScoresClass1,
                                  double[] weightsClass1)

Description copied from interface: NumericalPerformanceMeasure

This method allows to compute the performance measure of given sorted score ratios. This method can only be used for binary classifiers.

Specified by:

compute in interface NumericalPerformanceMeasure

Specified by:

compute in interface PerformanceMeasure

Specified by:

compute in class AbstractNumericalTwoClassPerformanceMeasure

Parameters:

sortedScoresClass0 - the sorted score ratios of class 0

weightsClass0 - the weights of the sequences of class 0 sorted along with the scores sortedScoresClass0

sortedScoresClass1 - the sorted score ratios of class 1

weightsClass1 - the weights of the sequences of class 1 sorted along with the scores sortedScoresClass1

Returns:

a result set containing the results of the performance measure

See Also:

de.jstacs.utils.ToolBox#sortAlongWith(double[], double[]...)