Incorporating multi-criteria ratings in recommendation systems

Recommendation systems utilize information techniques, to the problem of helping users find the items they would like. Example applications include the recommendation systems for movies, books, CDs and many others. As recommendation systems emerge as an independent research area, the rating structure plays a critical role in recent studies. Among many alternatives; the collaborative filtering algorithms are generally accepted to be successful to estimate user ratings of, unseen items and then to derive proper recommendations. In this paper, we extend the concept of single criterion ratings to multi-criteria ones, i.e., an item can be evaluated in many different aspects. Since there are usually conflicts among different criteria, the recommendation problem cannot be formulated as an optimization problem any more. Instead, we propose to use data query techniques to solve this multi-criteria recommendation problem.