es.upm.etsisi.cf4j.recommender.knn.userSimilarityMetric

Class JMSD

java.lang.Object

es.upm.etsisi.cf4j.recommender.knn.userSimilarityMetric.UserSimilarityMetric

es.upm.etsisi.cf4j.recommender.knn.userSimilarityMetric.JMSD

All Implemented Interfaces:

Partible<User>

public class JMSD
extends UserSimilarityMetric

Implements the following CF similarity metric: Bobadilla, J., Serradilla, F., & Bernal, J. (2010). A new collaborative filtering metric that improves the behavior of Recommender Systems, Knowledge-Based Systems, 23 (6), 520-528.

Field Summary

Fields inherited from class es.upm.etsisi.cf4j.recommender.knn.userSimilarityMetric.UserSimilarityMetric

datamodel, similarities

Constructor Summary

Constructors

Constructor and Description
JMSD()

Method Summary

Modifier and Type	Method and Description
void	beforeRun() Is executed once before execute the method 'exec'.
double	similarity(User user, User otherUser) This method must returns the similarity between two users.

Methods inherited from class es.upm.etsisi.cf4j.recommender.knn.userSimilarityMetric.UserSimilarityMetric

afterRun, getSimilarities, run, setDatamodel, toString

Methods inherited from class java.lang.Object

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

Constructor Detail

JMSD

public JMSD()

Method Detail

beforeRun

public void beforeRun()

Description copied from interface: Partible

Is executed once before execute the method 'exec'. It can be used to initialize resources.

Specified by:

beforeRun in interface Partible<User>

Overrides:

beforeRun in class UserSimilarityMetric

similarity

public double similarity(User user,
                         User otherUser)

Description copied from class: UserSimilarityMetric

This method must returns the similarity between two users.

If two users do not have a similarity value, the method must return Double.NEGATIVE_INFINITY.

The value returned by this method should be higher the greater the similarity between users.

Specified by:

similarity in class UserSimilarityMetric

Parameters:

user - A user

otherUser - Other user

Returns:

Similarity between user and otherUser