org.lenskit.bias

Class BiasItemScorer

java.lang.Object

org.lenskit.basic.AbstractItemScorer

org.lenskit.bias.BiasItemScorer

All Implemented Interfaces:

ItemScorer

public class BiasItemScorer
extends AbstractItemScorer

Score items using a user-item bias model. This scorer is good as a baseline scorer for many situations.

Constructor Summary

Constructors

Constructor and Description
BiasItemScorer(BiasModel bias) Construct a new scorer.

Method Summary

Modifier and Type	Method and Description
Result	score(long user, long item) Score a single item.
ResultMap	scoreWithDetails(long user, Collection<Long> items) Score a collection of items and potentially return more details on the scores.

Methods inherited from class org.lenskit.basic.AbstractItemScorer

score

Methods inherited from class java.lang.Object

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

Constructor Detail

BiasItemScorer

@Inject
public BiasItemScorer(BiasModel bias)

Construct a new scorer.

Parameters:

bias - The bias model to use.

Method Detail

score

public Result score(long user,
                    long item)

Description copied from class: AbstractItemScorer

Score a single item.

This implementation delegates to ItemScorer.scoreWithDetails(long, Collection).

Specified by:

score in interface ItemScorer

Overrides:

score in class AbstractItemScorer

Parameters:

user - The user ID for whom to generate a score.

item - The item ID to score.

Returns:

The score, or null if no score can be generated.

scoreWithDetails

@Nonnull
public ResultMap scoreWithDetails(long user,
                                            @Nonnull
                                            Collection<Long> items)

Description copied from interface: ItemScorer

Score a collection of items and potentially return more details on the scores.

Parameters:

user - The user ID for whom to generate scores.

items - The item to score.

Returns:

The scores for the items. This result set may not contain all requested items. Implementations that support additional details will return a subclass of ResultMap that provides access to those details.