Guess Who Rated This Movie: Identifying Users Through Subspace Clustering
Amy Zhang, Nadia Fawaz, Stratis Ioannidis, Andrea Montanari
It is often the case that, within an online recommender system, multiple users share a common account. Can such shared accounts be identified solely on the basis of the userprovided ratings? Once a shared account is identified, can the different users sharing it be identified as well? Whenever such user identification is feasible, it opens the way to possible improvements in personalized recommendations, but also raises privacy concerns. We develop a model for composite accounts based on unions of linear subspaces, and use subspace clustering for carrying out the identification task. We show that a significant fraction of such accounts is identifiable in a reliable manner, and illustrate potential uses for personalized recommendation.
PDF Link: /papers/12/p944-zhang.pdf
AUTHOR = "Amy Zhang
and Nadia Fawaz and Stratis Ioannidis and Andrea Montanari",
TITLE = "Guess Who Rated This Movie: Identifying Users Through Subspace Clustering",
BOOKTITLE = "Proceedings of the Twenty-Eighth Conference Annual Conference on Uncertainty in Artificial Intelligence (UAI-12)",
PUBLISHER = "AUAI Press",
ADDRESS = "Corvallis, Oregon",
YEAR = "2012",
PAGES = "944--953"