jsat.classifiers.evaluation

Class SimpleBinaryClassMetric

java.lang.Object

jsat.classifiers.evaluation.SimpleBinaryClassMetric

All Implemented Interfaces:

Serializable, ClassificationScore

Direct Known Subclasses:

F1Score, FbetaScore, MatthewsCorrelationCoefficient, Precision, Recall

public abstract class SimpleBinaryClassMetric
extends Object
implements ClassificationScore

This is a base class for scores that can be computed from simple counts of the true positives, true negatives, false positives, and false negatives. The class with index zero will be considered the positive class and the class with the first index will be the negative class.

By default this class assumes higher scores are better

Author:

Edward Raff

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
protected double	fn false negatives
protected double	fp false positives
protected double	tn true negatives
protected double	tp true positives

Constructor Summary

Constructors

Constructor and Description
SimpleBinaryClassMetric()
SimpleBinaryClassMetric(SimpleBinaryClassMetric toClone)

Method Summary

Modifier and Type	Method and Description
void	addResult(CategoricalResults prediction, int trueLabel, double weight) Adds the given result to the score
void	addResults(ClassificationScore other) The score contained in this object is augmented with the results already accumulated in the other object.
abstract SimpleBinaryClassMetric	clone()
abstract double	getScore() Computes the score for the results that have been enrolled via ClassificationScore.addResult(jsat.classifiers.CategoricalResults, int, double)
boolean	lowerIsBetter() Returns true if a lower score is better, or false if a higher score is better
void	prepare(CategoricalData toPredict) Prepares this score to predict on the given input

Methods inherited from class java.lang.Object

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

Methods inherited from interface jsat.classifiers.evaluation.ClassificationScore

equals, getName, hashCode

Field Detail

tp

protected double tp

true positives

tn

protected double tn

true negatives

fp

protected double fp

false positives

fn

protected double fn

false negatives

Constructor Detail

SimpleBinaryClassMetric

public SimpleBinaryClassMetric()

SimpleBinaryClassMetric

public SimpleBinaryClassMetric(SimpleBinaryClassMetric toClone)

Method Detail

addResult

public void addResult(CategoricalResults prediction,
                      int trueLabel,
                      double weight)

Description copied from interface: ClassificationScore

Adds the given result to the score

Specified by:

addResult in interface ClassificationScore

Parameters:

prediction - the prediction for the data point

trueLabel - the true label for the data point

weight - the weigh to assign to the data point

prepare

public void prepare(CategoricalData toPredict)

Description copied from interface: ClassificationScore

Prepares this score to predict on the given input

Specified by:

prepare in interface ClassificationScore

Parameters:

toPredict - the class label information that will be evaluated

addResults

public void addResults(ClassificationScore other)

Description copied from interface: ClassificationScore

The score contained in this object is augmented with the results already accumulated in the other object. This does not result in an averaging, but alters the current object to have the same score it would have had if all the results were originally inserted into this object.

This method is only required to work if other if of the same class as this object.

Specified by:

addResults in interface ClassificationScore

Parameters:

other - the object to add the results from

getScore

public abstract double getScore()

Description copied from interface: ClassificationScore

Computes the score for the results that have been enrolled via ClassificationScore.addResult(jsat.classifiers.CategoricalResults, int, double)

Specified by:

getScore in interface ClassificationScore

Returns:

the score for the current results

lowerIsBetter

public boolean lowerIsBetter()

Description copied from interface: ClassificationScore

Returns true if a lower score is better, or false if a higher score is better

Specified by:

lowerIsBetter in interface ClassificationScore

Returns:

true if a lower score is better

clone

public abstract SimpleBinaryClassMetric clone()

Specified by:

clone in interface ClassificationScore

Overrides:

clone in class Object