es.upm.etsisi.cf4j.util.optimization

Class GridSearch

java.lang.Object

es.upm.etsisi.cf4j.util.optimization.GridSearch

public class GridSearch
extends Object

Utility class to performs a grid search over a Recommender instance. The Recommender class used during the grid search must contains a constructor with the signature Recommender::<init>(DataModel, Map<String, Object>) that initializes the Recommender using the attributes defined in the Map object. The parameters used in the search process, i.e. the development set, must be defined in a ParamsGrid instance. The grid search is executed in such a way that it minimizes (by default) or maximizes a QualityMeasure instance. If the QualityMeasure requires parameters to work, it must contains a constructor with the signature QualityMeasure::<init>(Recommender, Map<String, Object>) that initializes the QualityMeasure using the attributes defined in the Map object.

Constructor Summary

Constructors

Constructor and Description
GridSearch(DataModel datamodel, ParamsGrid grid, Class<? extends Recommender> recommenderClass, Class<? extends QualityMeasure> qualityMeasureClass) GridSearch constructor
GridSearch(DataModel datamodel, ParamsGrid grid, Class<? extends Recommender> recommenderClass, Class<? extends QualityMeasure> qualityMeasureClass, Map<String,Object> qualityMeasureParams) GridSearch constructor

Method Summary

Modifier and Type	Method and Description
void	fit() Performs grid search
void	printResults() Prints the results of the grid search.
void	printResults(boolean lowerIsBetter) Prints the results of the grid search
void	printResults(int topN) Prints the results of the grid search
void	printResults(int topN, boolean lowerIsBetter) Prints the results of the grid search
void	printResults(String numberFormat) Prints the results of the grid search.
void	printResults(String numberFormat, boolean lowerIsBetter) Prints the results of the grid search
void	printResults(String numberFormat, int topN) Prints the results of the grid search
void	printResults(String numberFormat, int topN, boolean lowerIsBetter) Prints the results of the grid search

Methods inherited from class java.lang.Object

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

Constructor Detail

GridSearch

public GridSearch(DataModel datamodel,
                  ParamsGrid grid,
                  Class<? extends Recommender> recommenderClass,
                  Class<? extends QualityMeasure> qualityMeasureClass)

GridSearch constructor

Parameters:

datamodel - DataModel instance

grid - ParamsGrid instance containing the development set

recommenderClass - Recommender class to be evaluated

qualityMeasureClass - QualityMeasure class used to evaluate the Recommender

GridSearch

public GridSearch(DataModel datamodel,
                  ParamsGrid grid,
                  Class<? extends Recommender> recommenderClass,
                  Class<? extends QualityMeasure> qualityMeasureClass,
                  Map<String,Object> qualityMeasureParams)

GridSearch constructor

Parameters:

datamodel - DataModel instance

grid - ParamsGrid instance containing the development set

recommenderClass - Recommender class to be evaluated. This class must contains a constructor with the signature Recommender.<init>(DataModel, Map<String, Object>)

qualityMeasureClass - QualityMeasure class used to evaluate the Recommender. This class must contains a constricutor with the signautre QualityMeasure.<init>(Recommender, Map<String, Object>)

qualityMeasureParams - Map object containing the quality measure parameters names (keys) and values (value)

Method Detail

fit

public void fit()

Performs grid search

printResults

public void printResults()

Prints the results of the grid search. By default, the quality measure is better the lower its value.

printResults

public void printResults(int topN)

Prints the results of the grid search

Parameters:

topN - Number of entries of the development set to be shown as the top ones

printResults

public void printResults(String numberFormat)

Prints the results of the grid search. By default, the quality measure is better the lower its value.

Parameters:

numberFormat - Number format for the quality measure values

printResults

public void printResults(boolean lowerIsBetter)

Prints the results of the grid search

Parameters:

lowerIsBetter - True if the quality measure is better the lower its value. False otherwise.

printResults

public void printResults(String numberFormat,
                         int topN)

Prints the results of the grid search

Parameters:

numberFormat - Number format for the quality measure values

topN - Number of entries of the development set to be shown as the top ones

printResults

public void printResults(int topN,
                         boolean lowerIsBetter)

Prints the results of the grid search

Parameters:

topN - Number of entries of the development set to be shown as the top ones

lowerIsBetter - True if the quality measure is better the lower its value. False otherwise.

printResults

public void printResults(String numberFormat,
                         boolean lowerIsBetter)

Prints the results of the grid search

Parameters:

numberFormat - Number format for the quality measure values

lowerIsBetter - True if the quality measure is better the lower its value. False otherwise.

printResults

public void printResults(String numberFormat,
                         int topN,
                         boolean lowerIsBetter)

Prints the results of the grid search

Parameters:

numberFormat - Number format for the quality measure values

topN - Number of entries of the development set to be shown as the top ones

lowerIsBetter - True if the quality measure is better the lower its value. False otherwise.