skip to main content
10.1145/2043932.2043973acmconferencesArticle/Chapter ViewAbstractPublication PagesrecsysConference Proceedingsconference-collections
poster

A probabilistic definition of item similarity

Published: 23 October 2011 Publication History

Abstract

In item-based collaborative filtering, a critical intermediate step to personalized recommendations is the definition of an item-similarity metric. Existing algorithms compute the item-similarity using the user-to-item ratings (cosine, Pearson, Jaccard, etc.). When computing the similarity between two items A and B many of these algorithms divide the actual number of co-occurring users by some "difficulty" of co-occurrence. We refine this approach by defining item similarity as the ratio of the actual number of co-occurrences to the number of co-occurrences that would be expected if user choices were random. In the final step of our method to compute personalized recommendations we apply the usage history of a user to the item similarity matrix. The well defined probabilistic meaning of our similarities allows us to further improve this final step. We measured the quality of our algorithm on a large real-world data-set. As part of Comcast's efforts to improve its personalized recommendations of movies and TV shows, several top recommender companies were invited to apply their algorithms to one year of Video-on-Demand usage data. Our algorithm tied for first place. This paper includes a MapReduce pseudo code implementation of our algorithm.

References

[1]
Gediminas Adomavicius, I. and I. Alexander Tuzhilin, Toward the Next Generation of Recommender Systems: A Survey of the State-of-the-Art and Possible Extensions. Knowledge and Data Engineering, IEEE Transactions on, 2005. 17(6): p. 734--749.
[2]
Melville, P. and V. Sindhwani, Recommender Systems. Encyclopedia of Machine Learning, 2010.
[3]
Resnick., P. and H.R. Varian, Recommender systems. Communications of the ACM, 1997. 40(3).
[4]
Miller, B.N., et al., MovieLens unplugged: experiences with an occasionally connected recommender system, in Proceedings of the 8th international conference on Intelligent user interfaces 2003: New York, NY.
[5]
Bambini, R., P. Cremonesi, and R. Turrin, A Recommender System for an IPTV Service Provider: a Real Large-Scale Production Environment. Recommender Systems Handbook, 2011: p. 299--331.
[6]
Herlocker, J.L., et al., Evaluating collaborative filtering recommender systems. ACM Transactions on Information Systems (TOIS), 2004. 22(1).
[7]
Su, X. and T.M. Khoshgoftaar, A survey of collaborative filtering techniques. Advances in Artificial Intelligence, 2009.
[8]
Cantador, I., A. Bellogín, and D. Vallet. Content-based recommendation in social tagging systems. in Proceedings of the fourth ACM conference on Recommender systems. 2010. Barcelona.
[9]
Musto, C., Enhanced vector space models for content-based recommender systems, in Proceedings of the fourth ACM conference on Recommender systems. 2010: Bari, Italy.
[10]
Lekakos, G. and P. Caravelas, A hybrid approach for movie recommendation. MULTIMEDIA TOOLS AND APPLICATIONS, 2008. 36(1-2): p. 55--70.
[11]
1Karypis, G. Evaluation of Item-Based Top-N Recommendation Algorithms. in Proceedings of the tenth international conference on Information and knowledge management. 2001. New York, NY.
[12]
Sarwar, B., et al. Item-based collaborative filtering recommendation algorithms. in Proceedings of WWW '01 Proceedings of the 10th international conference on World Wide Web. 2001. New York, NY.
[13]
Liang, H., et al. Collaborative Filtering Recommender Systems Using Tag Information. in International Conference on Web Intelligence and Intelligent Agent Technology. 2008.
[14]
Gong, S., An Efficient Collaborative Recommendation Algorithm Based on Item Clustering. ADVANCES IN WIRELESS NETWORKS AND INFORMATION SYSTEMS, 2010. 72.
[15]
Jiang, F. and Z. Wang, Pagerank-Based Collaborative Filtering Recommendation. INFORMATION COMPUTING AND APPLICATIONS, 2010. 6377.
[16]
Schlieder, C., Modeling Collaborative Semantics with a Geographic Recommender. ADVANCES IN CONCEPTUAL MODELING -- FOUNDATIONS AND APPLICATIONS, 2007. 4802.
[17]
Ahn, H.J., A new similarity measure for collaborative filtering to alleviate the new user cold-starting problem. Information Sciences, 2008. 178(1): p. 37--51.
[18]
Anand, D. and K.K. Bharadwaj, Utilizing various sparsity measures for enhancing accuracy of collaborative recommender systems based on local and global similarities. Expert Systems with Applications, 2011. 38(5).
[19]
Wang, J., et al., Probabilistic relevance ranking for collaborative filtering. INFORMATION RETRIEVAL, 2008. 11(6).
[20]
Töscher, A., M. Jahrer, and R. Legenstein. Improved neighborhood-based algorithms for large-scale recommender systems. in Proceedings of the 2nd KDD Workshop on Large-Scale Recommender Systems and the Netflix Prize Competition. 2008. New York, NY.
[21]
2Koren, Y. Factorization meets the neighborhood: a multifaceted collaborative filtering model. in Proceeding of the 14th ACM SIGKDD international conference on Knowledge discovery and data mining. 2008. New York, NY.
[22]
2Gunawardana, A. and G. Shani, A Survey of Accuracy Evaluation Metrics of Recommendation Tasks. The Journal of Machine Learning Research, 2009. 10.
[23]
Ormándi, R., I. Hegedqs, and M. Jelasity, Overlay Management for Fully Distributed User-Based Collaborative Filtering Lecture Notes in Computer Science, 2010. 6271.
[24]
Zhao, Z.-D. and M.-s. Shang. User-based collaborative-filtering recommendation algorithms on hadoop. in Third International Conference on Knowledge Discovery and Data Mining. 2010. Phuket, Thailan.
[25]
Fu, C. and Z. Leng. A Framework for Recommender Systems in E-Commerce Based on Distributed Storage and Data-Mining. in 2010 International Conference on E-Business and E-Government. 2010. Guangzhou, Chin.
[26]
GroupLens Research. Available from: http://www.grouplens.org/node/12.
[27]
Apache Foundation. Available from: http://mahout.apache.org/.

Cited By

View all
  • (2022)Learning to Rank Instant Search Results with Multiple IndicesProceedings of the 45th International ACM SIGIR Conference on Research and Development in Information Retrieval10.1145/3477495.3536334(3412-3416)Online publication date: 6-Jul-2022
  • (2018)Intelligent prediction and recommendation optimization method based on fuzzy clustering and time weightingProceedings of the 20th International Conference on Information Integration and Web-based Applications & Services10.1145/3282373.3282394(79-84)Online publication date: 19-Nov-2018
  • (2018)Recommendation diversification using a weighted similarity measure in user based collaborative filtering2018 International Symposium on Programming and Systems (ISPS)10.1109/ISPS.2018.8379011(1-6)Online publication date: Apr-2018
  • Show More Cited By

Recommendations

Comments

Information & Contributors

Information

Published In

cover image ACM Conferences
RecSys '11: Proceedings of the fifth ACM conference on Recommender systems
October 2011
414 pages
ISBN:9781450306836
DOI:10.1145/2043932
Permission to make digital or hard copies of all or part of this work for personal or classroom use is granted without fee provided that copies are not made or distributed for profit or commercial advantage and that copies bear this notice and the full citation on the first page. Copyrights for components of this work owned by others than ACM must be honored. Abstracting with credit is permitted. To copy otherwise, or republish, to post on servers or to redistribute to lists, requires prior specific permission and/or a fee. Request permissions from [email protected]

Sponsors

In-Cooperation

Publisher

Association for Computing Machinery

New York, NY, United States

Publication History

Published: 23 October 2011

Permissions

Request permissions for this article.

Check for updates

Author Tags

  1. recommender systems
  2. similarity computation
  3. usage-based recommendations

Qualifiers

  • Poster

Conference

RecSys '11
Sponsor:
RecSys '11: Fifth ACM Conference on Recommender Systems
October 23 - 27, 2011
Illinois, Chicago, USA

Acceptance Rates

Overall Acceptance Rate 254 of 1,295 submissions, 20%

Contributors

Other Metrics

Bibliometrics & Citations

Bibliometrics

Article Metrics

  • Downloads (Last 12 months)7
  • Downloads (Last 6 weeks)0
Reflects downloads up to 05 Mar 2025

Other Metrics

Citations

Cited By

View all
  • (2022)Learning to Rank Instant Search Results with Multiple IndicesProceedings of the 45th International ACM SIGIR Conference on Research and Development in Information Retrieval10.1145/3477495.3536334(3412-3416)Online publication date: 6-Jul-2022
  • (2018)Intelligent prediction and recommendation optimization method based on fuzzy clustering and time weightingProceedings of the 20th International Conference on Information Integration and Web-based Applications & Services10.1145/3282373.3282394(79-84)Online publication date: 19-Nov-2018
  • (2018)Recommendation diversification using a weighted similarity measure in user based collaborative filtering2018 International Symposium on Programming and Systems (ISPS)10.1109/ISPS.2018.8379011(1-6)Online publication date: Apr-2018
  • (2018)An expert recommendation algorithm based on Pearson correlation coefficient and FP-growthCluster Computing10.1007/s10586-017-1576-y22:S3(7401-7412)Online publication date: 3-Jan-2018
  • (2016)Events detection and community partition based on probabilistic snapshot for evolutionary social networkPeer-to-Peer Networking and Applications10.1007/s12083-016-0427-610:6(1272-1284)Online publication date: 1-Feb-2016

View Options

Login options

View options

PDF

View or Download as a PDF file.

PDF

eReader

View online with eReader.

eReader

Figures

Tables

Media

Share

Share

Share this Publication link

Share on social media