org.lenskit.api

Interface ItemBasedItemRecommender

All Known Implementing Classes:

AbstractItemBasedItemRecommender, TopNItemBasedItemRecommender

public interface ItemBasedItemRecommender

Recommends items that go with a set of reference items. This interface is distinguished from ItemRecommender in that it uses a set of reference items instead of a user as the basis for computing scores.

Since:

0.10

See Also:

ItemRecommender

Compatibility

Public

Method Summary

Modifier and Type	Method and Description
List<Long>	recommendRelatedItems(long reference) Recommend all possible items for a reference item using the default exclude set.
List<Long>	recommendRelatedItems(long reference, int n) Recommend up to n possible items for a reference item using the default exclude set.
List<Long>	recommendRelatedItems(Set<Long> basket) Recommend all possible items for a set of reference items using the default exclude set.
List<Long>	recommendRelatedItems(Set<Long> basket, int n) Recommend up to n items for a set of reference items using the default exclude set.
List<Long>	recommendRelatedItems(Set<Long> basket, int n, Set<Long> candidates, Set<Long> exclude) Produce a set of recommendations for the item.
ResultList	recommendRelatedItemsWithDetails(Set<Long> basket, int n, Set<Long> candidates, Set<Long> exclude) Produce a set of recommendations for the item, with details.

Method Detail

recommendRelatedItems

List<Long> recommendRelatedItems(long reference)

Recommend all possible items for a reference item using the default exclude set.

Parameters:

reference - The reference item.

Returns:

The recommended items.

See Also:

recommendRelatedItems(Set, int, Set, Set)

recommendRelatedItems

List<Long> recommendRelatedItems(long reference,
                                 int n)

Recommend up to n possible items for a reference item using the default exclude set.

Parameters:

reference - The reference item.

n - The number of items to recommend (< 0 for unlimited).

Returns:

The recommended items.

See Also:

recommendRelatedItems(Set, int, Set, Set)

recommendRelatedItems

List<Long> recommendRelatedItems(Set<Long> basket)

Recommend all possible items for a set of reference items using the default exclude set.

Parameters:

basket - The reference items.

Returns:

The recommended items.

See Also:

recommendRelatedItems(Set, int, Set, Set)

recommendRelatedItems

List<Long> recommendRelatedItems(Set<Long> basket,
                                 int n)

Recommend up to n items for a set of reference items using the default exclude set.

Parameters:

basket - The reference items.

n - The number of recommendations to return (< 0 for unlimited).

Returns:

The recommended items.

See Also:

recommendRelatedItems(Set, int, Set, Set)

recommendRelatedItems

List<Long> recommendRelatedItems(Set<Long> basket,
                                 int n,
                                 @Nullable
                                 Set<Long> candidates,
                                 @Nullable
                                 Set<Long> exclude)

Produce a set of recommendations for the item. This method allows the recommendations to be constrained by both a candidate set and an exclude set. The exclude set is applied to the candidate set, so the final effective candidate set is candidates minus exclude.

Parameters:

basket - The reference items.

n - The number of ratings to return. If negative, no specific size is requested.

candidates - A set of candidate items which can be recommended. If null, all items are considered candidates.

exclude - A set of items to be excluded. If null, a default exclude set is used.

Returns:

A list of recommended items.

recommendRelatedItemsWithDetails

ResultList recommendRelatedItemsWithDetails(Set<Long> basket,
                                            int n,
                                            @Nullable
                                            Set<Long> candidates,
                                            @Nullable
                                            Set<Long> exclude)

Produce a set of recommendations for the item, with details. This is the most general recommendation method, allowing the recommendations to be constrained by both a candidate set and an exclude set and potentially providing more details on each recommendation. The exclude set is applied to the candidate set, so the final effective candidate set is candidates minus exclude.

Parameters:

basket - The reference items.

n - The number of ratings to return. If negative, no specific size is requested.

candidates - A set of candidate items which can be recommended. If null, all items are considered candidates.

exclude - A set of items to be excluded. If null, a default exclude set is used.

Returns:

A list of recommended items with recommendation details. If the recommender cannot assign meaningful scores, the scores will be Double.NaN.