org.grouplens.lenskit.slopeone

Class SlopeOneModelDataAccumulator

java.lang.Object

org.grouplens.lenskit.slopeone.SlopeOneModelDataAccumulator

public class SlopeOneModelDataAccumulator
extends Object

Constructor Summary

Constructors

Constructor and Description
SlopeOneModelDataAccumulator(double damping, ItemDAO dao) Creates an accumulator to process rating data and generate the necessary data for a SlopeOneItemScorer.

Method Summary

Modifier and Type	Method and Description
Long2ObjectMap<ImmutableSparseVector>	buildMatrix()
void	putItemPair(long id1, SparseVector itemVec1, long id2, SparseVector itemVec2) Puts the item pair into the accumulator.

Methods inherited from class java.lang.Object

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

Constructor Detail

SlopeOneModelDataAccumulator

public SlopeOneModelDataAccumulator(double damping,
                                    ItemDAO dao)

Creates an accumulator to process rating data and generate the necessary data for a SlopeOneItemScorer.

Parameters:

damping - A damping term for deviation calculations.

dao - The DataAccessObject interfacing with the data for the model

Method Detail

putItemPair

public void putItemPair(long id1,
                        SparseVector itemVec1,
                        long id2,
                        SparseVector itemVec2)

Puts the item pair into the accumulator.

Parameters:

id1 - The id of the first item.

itemVec1 - The rating vector of the first item.

id2 - The id of the second item.

itemVec2 - The rating vector of the second item.

buildMatrix

public Long2ObjectMap<ImmutableSparseVector> buildMatrix()

Returns:

A matrix of item deviation and corating values to be used by a SlopeOneItemScorer.