Package smile.validation.metric

Class MatthewsCorrelation

java.lang.Object

smile.validation.metric.MatthewsCorrelation

All Implemented Interfaces:

Serializable, ToDoubleBiFunction<int[],int[]>, ClassificationMetric

public class MatthewsCorrelation
extends Object
implements ClassificationMetric

Matthews correlation coefficient. The MCC is in essence a correlation coefficient between the observed and predicted binary classifications. It is considered as a balanced measure for binary classification, even in unbalanced data sets. It varies between -1 (perfect disagreement) and +1 (perfect agreement). When it is 0, the model is not better than random.

See Also:

• Serialized Form

Field Summary

Fields

Modifier and Type	Field	Description
static final MatthewsCorrelation	instance	Default instance.

Constructor Summary

Constructors

Constructor	Description
MatthewsCorrelation()

Method Summary

Modifier and Type	Method	Description
static double	of(int[] truth, int[] prediction)	Calculates Matthews correlation coefficient.
double	score(int[] truth, int[] prediction)	Returns a score to measure the quality of classification.
String	toString()

Methods inherited from class java.lang.Object

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

Methods inherited from interface smile.validation.metric.ClassificationMetric

applyAsDouble

Field Details

instance

public static final MatthewsCorrelation instance

Default instance.

Constructor Details

MatthewsCorrelation

public MatthewsCorrelation()

Method Details

score

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

Description copied from interface: ClassificationMetric

Returns a score to measure the quality of classification.

Specified by:

score in interface ClassificationMetric

Parameters:

truth - the true class labels.

prediction - the predicted class labels.

Returns:

the metric.

of

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

Calculates Matthews correlation coefficient.

Parameters:

truth - the ground truth.

prediction - the prediction.

Returns:

the metric.

toString

public String toString()

Overrides:

toString in class Object