Skip to Main content Skip to Navigation
Journal articles

EBCR: Empirical Bayes concordance ratio method to improve similarity measurement in memory-based collaborative filtering

Abstract : Recommender systems aim to provide users with a selection of items, based on predicting their preferences for items they have not yet rated, thus helping them filter out irrelevant ones from a large product catalogue. Collaborative filtering is a widely used mechanism to predict a particular user's interest in a given item, based on feedback from neighbour users with similar tastes. The way the user's neighbourhood is identified has a significant impact on prediction accuracy. Most methods estimate user proximity from ratings they assigned to co-rated items, regardless of their number. This paper introduces a similarity adjustment taking into account the number of co-ratings. The proposed method is based on a concordance ratio representing the probability that two users share the same taste for a new item. The probabilities are further adjusted by using the Empirical Bayes inference method before being used to weight similarities. The proposed approach improves existing similarity measures without increasing time complexity and the adjustment can be combined with all existing similarity measures. Experiments conducted on benchmark datasets confirmed that the proposed method systematically improved the recommender system's prediction accuracy performance for all considered similarity measures.
Document type :
Journal articles
Complete list of metadata
Contributor : Administrateur Imt - Mines Alès Connect in order to contact the contributor
Submitted on : Friday, August 13, 2021 - 10:12:08 AM
Last modification on : Friday, October 22, 2021 - 2:38:02 PM
Long-term archiving on: : Sunday, November 14, 2021 - 6:06:17 PM


Publisher files allowed on an open archive


Distributed under a Creative Commons Attribution 4.0 International License



Yu Du, Nicolas Sutton-Charani, Sylvie Ranwez, Vincent Ranwez. EBCR: Empirical Bayes concordance ratio method to improve similarity measurement in memory-based collaborative filtering. PLoS ONE, Public Library of Science, 2021, pp.1-19. ⟨10.1371/journal.pone.0255929⟩. ⟨hal-03319825⟩



Les métriques sont temporairement indisponibles