org.grouplens.lenskit.knn.item

Interface NeighborhoodScorer

All Known Implementing Classes:

SimilaritySumNeighborhoodScorer, WeightedAverageNeighborhoodScorer

@DefaultImplementation(value=WeightedAverageNeighborhoodScorer.class)
public interface NeighborhoodScorer

Compute scores from neighborhoods and score vectors.

This interface encapsulates aggregating user scores and item similarities into a final score. The neighborhood is pre-filtered to only contain items for which scores are available, and truncated to the neighborhood size, so all functions implementing this interface need to do is accumulate scores.

Method Summary

Modifier and Type	Method and Description
ScoredId	score(long item, SparseVector neighbors, SparseVector scores) Compute a score based on similar neighbors and their corresponding scores.

Method Detail

score

ScoredId score(long item,
               SparseVector neighbors,
               SparseVector scores)

Compute a score based on similar neighbors and their corresponding scores.

Parameters:

item -

neighbors - A vector of neighbors with similarity measures.

scores - A vector of item scores. It should contain a score for every item in neighbors.

Returns:

An accumulated score from the neighbors, or null if no score could be computed.