es.uam.eps.ir.ranksys.diversity.binom.metrics

Class BinomialNonRedundancy<U,I,F>

java.lang.Object

es.uam.eps.ir.ranksys.metrics.AbstractRecommendationMetric<U,I>

es.uam.eps.ir.ranksys.diversity.binom.metrics.BinomialMetric<U,I,F>

es.uam.eps.ir.ranksys.diversity.binom.metrics.BinomialNonRedundancy<U,I,F>

Type Parameters:

U - type of the users

I - type of the items

F - type of the features

All Implemented Interfaces:

RecommendationMetric<U,I>

public class BinomialNonRedundancy<U,I,F>
extends BinomialMetric<U,I,F>

Binomial redundancy metric. S. Vargas, L. Baltrunas, A. Karatzoglou, P. Castells. Coverage, redundancy and size-awareness in genre diversity for Recommender Systems. RecSys 2014.

Author:

Saúl Vargas (saul.vargas@uam.es)

Field Summary

Fields inherited from class es.uam.eps.ir.ranksys.diversity.binom.metrics.BinomialMetric

relModel

Constructor Summary

Constructors

Constructor and Description
BinomialNonRedundancy(BinomialModel<U,I,F> binomialModel, FeatureData<I,F,?> featureData, int cutoff, RelevanceModel<U,I> relModel) Constructor.

Method Summary

Modifier and Type	Method and Description
protected double	getResultFromCount(BinomialModel.UserBinomialModel prob, it.unimi.dsi.fastutil.objects.Object2IntMap<F> count, int nrel, int nret) Result of the metric based on the number of times each features appears in a recommendation list.
protected static <U,I,F> double	nonRedundancy(BinomialModel.UserBinomialModel ubm, it.unimi.dsi.fastutil.objects.Object2IntMap<F> count, int nrel) Returns the value of the binomial redundancy metric for a given count of features from a recommendation list.

Methods inherited from class es.uam.eps.ir.ranksys.diversity.binom.metrics.BinomialMetric

evaluate

Methods inherited from class java.lang.Object

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

Constructor Detail

BinomialNonRedundancy

public BinomialNonRedundancy(BinomialModel<U,I,F> binomialModel,
                             FeatureData<I,F,?> featureData,
                             int cutoff,
                             RelevanceModel<U,I> relModel)

Constructor.

Parameters:

binomialModel - binomial diversity model

featureData - feature data

cutoff - maximum length of the recommendation list to be evaluated

relModel - relevance model

Method Detail

getResultFromCount

protected double getResultFromCount(BinomialModel.UserBinomialModel prob,
                                    it.unimi.dsi.fastutil.objects.Object2IntMap<F> count,
                                    int nrel,
                                    int nret)

Description copied from class: BinomialMetric

Result of the metric based on the number of times each features appears in a recommendation list.

Specified by:

getResultFromCount in class BinomialMetric<U,I,F>

Parameters:

prob - user binomial model

count - count map of each feature in a recommendation

nrel - number of relevant items in the recommendation

nret - length of the recommendation

Returns:

value of the metric

nonRedundancy

protected static <U,I,F> double nonRedundancy(BinomialModel.UserBinomialModel ubm,
                                              it.unimi.dsi.fastutil.objects.Object2IntMap<F> count,
                                              int nrel)

Returns the value of the binomial redundancy metric for a given count of features from a recommendation list.

Type Parameters:

U - type of the users

I - type of the items

F - type of the features

Parameters:

ubm - user binomial model

count - count map of each feature in a recommendation

nrel - number of relevant items in the recommendation

Returns:

value of the binomial redundancy