smile.validation

Class Specificity

java.lang.Object

smile.validation.Specificity

All Implemented Interfaces:

ClassificationMeasure

public class Specificity
extends java.lang.Object
implements ClassificationMeasure

Specificity (SPC) or True Negative Rate is a statistical measures of the performance of a binary classification test. Specificity measures the proportion of negatives which are correctly identified.

SPC = TN / N = TN / (FP + TN) = 1 - FPR

Sensitivity and specificity are closely related to the concepts of type I and type II errors. For any test, there is usually a trade-off between the measures. This trade-off can be represented graphically using an ROC curve.

In this implementation, the class label 1 is regarded as positive and 0 is regarded as negative.

Field Summary

Fields

Modifier and Type	Field and Description
static Specificity	instance

Constructor Summary

Constructors

Constructor and Description
Specificity()

Method Summary

Modifier and Type	Method and Description
double	measure(int[] truth, int[] prediction) Returns an index to measure the quality of classification.
static double	of(int[] truth, int[] prediction) Calculates the specificity.
java.lang.String	toString()

Methods inherited from class java.lang.Object

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

Field Detail

instance

public static final Specificity instance

Constructor Detail

Specificity

public Specificity()

Method Detail

measure

public double measure(int[] truth,
                      int[] prediction)

Description copied from interface: ClassificationMeasure

Returns an index to measure the quality of classification.

Specified by:

measure in interface ClassificationMeasure

Parameters:

truth - the true class labels.

prediction - the predicted class labels.

of

public static double of(int[] truth,
                        int[] prediction)

Calculates the specificity.

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object