Recommender systems are a ubiquitous e-commerce tool, and users have come to trust such systems to reduce the burden of navigating large information spaces and product catalogs. The preservation of this trust is important both for users and site owners, and is dependent upon the perception of recommender systems as objective, unbiased and accurate. However, recent research shows that this perception is not readily supported. Recommender systems present a security problem: attackers who cannot be readily distinguished from ordinary users may introduce biased data, altering the output of a recommender system almost at will. This talk will examine the vulnerabilities and robustness of different recommendation techniques in the face of the type of "profile injection" attacks described above, and consider how recommender systems can be secured. We will demonstrate a variety of attack models, and their impact on the most common recommendation algorithms, showing how a system's ratings may be manipulated. In response, I will show some algorithmic variants for recommendations that have relatively greater security properties, and I will also show recent results in detecting and remediating attacks to reduce their impact. The talk will conclude with a discussion of the question of trust in e-commerce systems more generally.
Robin Burke is an associate professor at the School of Computer Science, Telecommunications and Information Systems at DePaul University in Chicago, Illinois, where his research focuses on recommender systems and case-based reasoning. He is currently engaged in a project funded by the US National Science Foundation to study the security properties of recommendation algorithms. Dr. Burke has been working in the area of case-based reasoning for 20 years and was a pioneer in the application of case-based approaches to knowledge-based recommender systems. He has also studied hybrid recommendation algorithms, developing and implementing new system designs for multi-component recommender systems.
Sprecher: Prof. Robin Burke Wann: Freitag, 25. August 2006, 14:00 Uhr (s.t.) Wo: Seminarraum E.1.42, Universität Klagenfurt