Learning from What Others Know: Privacy Preserving Cross System Personalization

  • Bhaskar Mehta
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4511)


Recommender systems have been steadily gaining popularity and have been deployed by several service providers. Large scalable deployment has however highlighted one of the design problems of recommender systems: lack of interoperability. Users today often use multiple electronic systems offering recommendations, which cannot learn from one another. The result is that the end user has to often provide similar information and in some cases disjoint information. Intuitively, it seems that much can be improved with this situation: information learnt by one system could potentially be reused by another, to offer an overall improved personalization experience. In this paper, we provide an effective solution to this problem using Latent Semantic Models by learning a user model across multiple systems. A privacy preserving distributed framework is added around the traditional Probabilistic Latent Semantic Analysis framework, and practical aspects such as addition of new systems and items are also dealt with in this work.


Ranking Score Locally Linear Embedding Encryption Homomorphism Probabilistic Latent Semantic Analysis Large Scalable Deployment 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2007

Authors and Affiliations

  • Bhaskar Mehta
    • 1
  1. 1.L3S Researchzentrum/University of Hannover, Hannover 30177Germany

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