es.upm.etsisi.cf4j.qualityMeasure

Class QualityMeasure

java.lang.Object

es.upm.etsisi.cf4j.qualityMeasure.QualityMeasure

Direct Known Subclasses:

Coverage, Discovery, Diversity, F1, MAE, Max, MSE, MSLE, NDCG, Novelty, Perfect, Precision, R2, Recall, RMSE

public abstract class QualityMeasure
extends Object

Abstract class used to simplify the evaluation of collaborative filtering based recommendation models. To define a new quality measure, getScore(TestUser testUser, double[] predictions) must be encoded.

Field Summary

Fields

Modifier and Type	Field and Description
protected Recommender	recommender Recommender instance for which the quality measure are going to be computed

Constructor Summary

Constructors

Constructor and Description
QualityMeasure(Recommender recommender) Creates a new quality measure

Method Summary

Modifier and Type	Method and Description
double	getScore() Computes the quality measure of the recommender
double	getScore(int numThreads) Computes the quality measure of the recommender
protected abstract double	getScore(TestUser testUser, double[] predictions) Computes the quality measure score for a TestUser given the predictions for his/her test ratings

Methods inherited from class java.lang.Object

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

Field Detail

recommender

protected Recommender recommender

Recommender instance for which the quality measure are going to be computed

Constructor Detail

QualityMeasure

public QualityMeasure(Recommender recommender)

Creates a new quality measure

Parameters:

recommender - Recommender instance for which the quality measure are going to be computed

Method Detail

getScore

protected abstract double getScore(TestUser testUser,
                                   double[] predictions)

Computes the quality measure score for a TestUser given the predictions for his/her test ratings

Parameters:

testUser - TestUser for which the quality measure score is computed

predictions - Prediction value for the test items rated by the test user

Returns:

Quality measure score

getScore

public double getScore(int numThreads)

Computes the quality measure of the recommender

Parameters:

numThreads - Number of threads to compute de quality measure in parallel for each test user. Use all available threads by default.

Returns:

Quality measure score

getScore

public double getScore()

Computes the quality measure of the recommender

Returns:

Quality measure score