smile.math.distance

Class JaccardDistance<T>

java.lang.Object

smile.math.distance.JaccardDistance<T>

All Implemented Interfaces:

Distance<T[]>

public class JaccardDistance<T>
extends Object
implements Distance<T[]>

The Jaccard index, also known as the Jaccard similarity coefficient is a statistic used for comparing the similarity and diversity of sample sets. The Jaccard coefficient measures similarity between sample sets, and is defined as the size of the intersection divided by the size of the union of the sample sets. The Jaccard distance, which measures dissimilarity between sample sets, is complementary to the Jaccard coefficient and is obtained by subtracting the Jaccard coefficient from 1, or, equivalently, by dividing the difference of the sizes of the union and the intersection of two sets by the size of the union.

Author:

Haifeng Li

Constructor Summary

Constructors

Constructor and Description
JaccardDistance() Constructor.

Method Summary

Modifier and Type	Method and Description
static <T> double	d(Set<T> a, Set<T> b) Returns the Jaccard distance between sets.
double	d(T[] a, T[] b) Returns the distance measure between two objects.
String	toString()

Methods inherited from class java.lang.Object

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

Constructor Detail

JaccardDistance

public JaccardDistance()

Constructor.

Method Detail

toString

public String toString()

Overrides:

toString in class Object

d

public double d(T[] a,
                T[] b)

Description copied from interface: Distance

Returns the distance measure between two objects.

Specified by:

d in interface Distance<T[]>

d

public static <T> double d(Set<T> a,
                           Set<T> b)

Returns the Jaccard distance between sets.