es.upm.etsisi.cf4j.recommender.matrixFactorization

Class HPF

java.lang.Object

es.upm.etsisi.cf4j.recommender.Recommender

es.upm.etsisi.cf4j.recommender.matrixFactorization.HPF

public class HPF
extends Recommender

Implements Gopalan, P., Hofman, J. M., & Blei, D. M. (2015, July). Scalable Recommendation with Hierarchical Poisson Factorization. In UAI (pp. 326-335).

Field Summary

Fields

Modifier and Type	Field and Description
protected double	a
protected double	aPrime
protected double	bPrime
protected double	c
protected double	cPrime
protected static double	DEFAULT_A
protected static double	DEFAULT_A_PRIME
protected static double	DEFAULT_B_PRIME
protected static double	DEFAULT_C
protected static double	DEFAULT_C_PRIME
protected static double	DEFAULT_D_PRIME
protected double	dPrime
protected double[][]	gamma
protected double[][]	gammaRte
protected double[][]	gammaShp
protected double[]	kappaRte
protected double	kappaShp
protected double[][]	lambda
protected double[][]	lambdaRte
protected double[][]	lambdaShp
protected int	numFactors Number of latent factors
protected int	numIters Number of iterations
protected double[]	tauRte
protected double	tauShp

Fields inherited from class es.upm.etsisi.cf4j.recommender.Recommender

datamodel

Constructor Summary

Constructors

Constructor and Description
HPF(DataModel datamodel, int numFactors, int numIters) Models constructor
HPF(DataModel datamodel, int numFactors, int numIters, double a, double aPrime, double bPrime, double c, double cPrime, double dPrime) Models constructor
HPF(DataModel datamodel, int numFactors, int numIters, double a, double aPrime, double bPrime, double c, double cPrime, double dPrime, long seed) Models constructor
HPF(DataModel datamodel, int numFactors, int numIters, long seed) Models constructor
HPF(DataModel datamodel, Map<String,Object> params) Model constructor from a Map containing the model's hyper-parameters values.

Method Summary

Modifier and Type	Method and Description
void	fit() Estimates model parameters given the hyper-parameters
int	getNumFactors() Get the number of factors of the model
int	getNumIters() Get the number of iterations
double	predict(int userIndex, int itemIndex) Computes a rating prediction
String	toString()

Methods inherited from class es.upm.etsisi.cf4j.recommender.Recommender

getDataModel, predict

Methods inherited from class java.lang.Object

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

Field Detail

DEFAULT_A

protected static final double DEFAULT_A

See Also:

Constant Field Values

DEFAULT_A_PRIME

protected static final double DEFAULT_A_PRIME

See Also:

Constant Field Values

DEFAULT_B_PRIME

protected static final double DEFAULT_B_PRIME

See Also:

Constant Field Values

DEFAULT_C

protected static final double DEFAULT_C

See Also:

Constant Field Values

DEFAULT_C_PRIME

protected static final double DEFAULT_C_PRIME

See Also:

Constant Field Values

DEFAULT_D_PRIME

protected static final double DEFAULT_D_PRIME

See Also:

Constant Field Values

numFactors

protected final int numFactors

Number of latent factors

numIters

protected final int numIters

Number of iterations

a

protected final double a

aPrime

protected final double aPrime

bPrime

protected final double bPrime

c

protected final double c

cPrime

protected final double cPrime

dPrime

protected final double dPrime

gamma

protected final double[][] gamma

gammaShp

protected final double[][] gammaShp

gammaRte

protected final double[][] gammaRte

kappaShp

protected final double kappaShp

kappaRte

protected final double[] kappaRte

lambda

protected final double[][] lambda

lambdaShp

protected final double[][] lambdaShp

lambdaRte

protected final double[][] lambdaRte

tauShp

protected final double tauShp

tauRte

protected final double[] tauRte

Constructor Detail

HPF

public HPF(DataModel datamodel,
           Map<String,Object> params)

Model constructor from a Map containing the model's hyper-parameters values. Map object must contains the following keys:

• numFactors: int value with the number of latent factors.
• numIters:: int value with the number of iterations.
• a (optional): double value with the a hyper-parameter. If missing, it is set to 0.3.
• aPrime (optional): double value with the a' hyper-parameter. If missing, it is set to 0.3.
• bPrime (optional): double value with the b' hyper-parameter. If missing, it is set to 1.0.
• c (optional): double value with the c hyper-parameter. If missing, it is set to 0.3.
• cPrime (optional): double value with the c' hyper-parameter. If missing, it is set to 0.3.
• dPrime (optional): double value with the d' hyper-parameter. If missing, it is set to 1.0.
• seed (optional): random seed for random numbers generation. If missing, random value is used.

Parameters:

datamodel - DataModel instance

params - Model's hyper-parameters values

HPF

public HPF(DataModel datamodel,
           int numFactors,
           int numIters)

Models constructor

Parameters:

datamodel - DataModel instance

numFactors - Number of latent factors

numIters - Number of iterations

HPF

public HPF(DataModel datamodel,
           int numFactors,
           int numIters,
           long seed)

Models constructor

Parameters:

datamodel - DataModel instance

numFactors - Number of latent factors

numIters - Number of iterations

seed - Seed for random numbers generation

HPF

public HPF(DataModel datamodel,
           int numFactors,
           int numIters,
           double a,
           double aPrime,
           double bPrime,
           double c,
           double cPrime,
           double dPrime)

Models constructor

Parameters:

datamodel - DataModel instance

numFactors - Number of latent factors

numIters - Number of iterations

a - Model hyper-parameter. Read the paper for more information related to this hyper-parameter.

aPrime - Model hyper-parameter. Read the paper for more information related to this hyper-parameter.

bPrime - Model hyper-parameter. Read the paper for more information related to this hyper-parameter.

c - Model hyper-parameter. Read the paper for more information related to this hyper-parameter.

cPrime - Model hyper-parameter. Read the paper for more information related to this hyper-parameter.

dPrime - Model hyper-parameter. Read the paper for more information related to this hyper-parameter.

HPF

public HPF(DataModel datamodel,
           int numFactors,
           int numIters,
           double a,
           double aPrime,
           double bPrime,
           double c,
           double cPrime,
           double dPrime,
           long seed)

Models constructor

Parameters:

datamodel - DataModel instance

numFactors - Number of latent factors

numIters - Number of iterations

a - Model hyper-parameter. Read the paper for more information related to this hyper-parameter.

aPrime - Model hyper-parameter. Read the paper for more information related to this hyper-parameter.

bPrime - Model hyper-parameter. Read the paper for more information related to this hyper-parameter.

c - Model hyper-parameter. Read the paper for more information related to this hyper-parameter.

cPrime - Model hyper-parameter. Read the paper for more information related to this hyper-parameter.

dPrime - Model hyper-parameter. Read the paper for more information related to this hyper-parameter.

seed - Seed for random numbers generation

Method Detail

fit

public void fit()

Description copied from class: Recommender

Estimates model parameters given the hyper-parameters

Specified by:

fit in class Recommender

predict

public double predict(int userIndex,
                      int itemIndex)

Description copied from class: Recommender

Computes a rating prediction

Specified by:

predict in class Recommender

Parameters:

userIndex - Index of the user in the array of Users of the DataModel instance

itemIndex - Index of the item in the array of Items of the DataModel instance

Returns:

Prediction

toString

public String toString()

Overrides:

toString in class Object

getNumFactors

public int getNumFactors()

Get the number of factors of the model

Returns:

Number of factors

getNumIters

public int getNumIters()

Get the number of iterations

Returns:

Number of iterations