THE SCIENCE AND MAGIC OF USER AND EXPERT FEEDBACK FOR IMPROVING RECOMMENDATIONS
Dr. Xavier Amatriain (Telefonica)
Thursday, March 3, 2011
Recommender systems are playing a key role in the next web revolution as a practical alternative to traditional search for information access and filtering. Most of these systems use Collaborative Filtering techniques in which predictions are solely based on the feedback of the user and similar peers. Although this approach is considered relatively effective, it has reached some practical limitations such as the so-called Magic Barrier. Many of these limitations strive from the fact that explicit user feedback in the form of ratings is considered the ground truth. However, this feedback has a non-negligible amount of noise and inconsistencies. Furthermore, in most practical applications, we lack enough explicit feedback and would be better off using implicit feedback or usage data.
In the first part of my talk, I will present our studies in analyzing natural noise in explicit feedback and finding ways to overcome it to improve recommendation accuracy. I will also present our study of user implicit feedback and an approach to relate both kinds of information.
In the second part, I will introduce a radically different approach to recommendation that is based on the use of the opinions of experts instead of regular peers. I will show how this approach addresses many of the shortcomings of traditional Collaborative Filtering, generates recommendations that are better perceived by the users, and allows for new applications such as fully-privacy preserving recommendations.
Xavier Amatriain (PhD) is Research Scientist in Telefonica (Barcelona, Spain), where his current focus is on Recommender Systems, User Modeling, Data Mining, Social Networks, and neighboring Web Science areas. Previous to this, he was Research Director at the University of California Santa Barbara, where he worked on Multimedia and Immersive Systems and led the Allosphere project. During his PhD at the Universitat Pompeu Fabra, he was lead developer and coordinator of the award-winning CLAM project.
Xavier has authored more than 50 publications, holds several patents, and has been lecturing on Software Engineering, Information Retrieval, and Multimedia Systems in several universities for over 10 years. He currently teaches Information Systems for Managers at EADA Business School. He is also interested in software development and research management, and in particular in models of technology transfer and agile methods.