net.librec.recommender.cf.rating

Class NMFRecommender

java.lang.Object

net.librec.recommender.AbstractRecommender

net.librec.recommender.cf.rating.NMFRecommender

All Implemented Interfaces:

Recommender

@ModelData(value={"isRating","nmf","transUserFactors","transItemFactors"})
public class NMFRecommender
extends AbstractRecommender

Daniel D. Lee and H. Sebastian Seung, Algorithms for Non-negative Matrix Factorization, NIPS 2001.

Author:

guoguibing and Keqiang Wang

Field Summary

Fields

Modifier and Type	Field and Description
protected int	numFactors the number of latent factors;
protected int	numIterations the number of iterations

Fields inherited from class net.librec.recommender.AbstractRecommender

conf, context, decay, earlyStop, globalMean, isBoldDriver, isRanking, itemMappingData, lastLoss, LOG, loss, maxRate, minRate, numItems, numRates, numUsers, ratingScale, recommendedList, testMatrix, topN, trainMatrix, userMappingData, validMatrix, verbose

Constructor Summary

Constructors

Constructor and Description
NMFRecommender()

Method Summary

Methods

Modifier and Type	Method and Description
protected double	predict(int userIdx, int itemIdx) predict a specific rating for user userIdx on item itemIdx.
protected void	setup() setup
protected void	trainModel() train Model

Methods inherited from class net.librec.recommender.AbstractRecommender

cleanup, evaluate, evaluateMap, getContext, getDataModel, getRecommendedList, isConverged, loadModel, predict, recommend, recommend, recommendRank, recommendRating, saveModel, setContext

Methods inherited from class java.lang.Object

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

Field Detail

numFactors

protected int numFactors

the number of latent factors;

numIterations

protected int numIterations

the number of iterations

Constructor Detail

NMFRecommender

public NMFRecommender()

Method Detail

setup

protected void setup()
              throws LibrecException

Description copied from class: AbstractRecommender

setup

Overrides:

setup in class AbstractRecommender

Throws:

LibrecException - if error occurs during setup

trainModel

protected void trainModel()
                   throws LibrecException

Description copied from class: AbstractRecommender

train Model

Specified by:

trainModel in class AbstractRecommender

Throws:

LibrecException - if error occurs during training model

predict

protected double predict(int userIdx,
             int itemIdx)
                  throws LibrecException

predict a specific rating for user userIdx on item itemIdx.

Specified by:

predict in class AbstractRecommender

Parameters:

userIdx - user index

itemIdx - item index

Returns:

predictive rating for user userIdx on item itemIdx

Throws:

LibrecException - if error occurs