Proceedings of Third International Conference, ICTIR 2011, Bertinoro, Italy, September 12-14, 2011.The final publication is available at Springer via http://dx.doi.org/10.1007/978-3-642-23318-0_5Performance prediction is an appealing problem in Recommender Systems, as it enables an array of strategies for deciding when to deliver or hold back recommendations based on their foreseen accuracy. The problem, however, has been barely addressed explicitly in the area. In this paper, we propose adaptations of query clarity techniques from ad-hoc Information Retrieval to define performance predictors in the context of Recommender Systems, which we refer to as user clarity. Our experiments show positive results with different user clarity models in terms of the correlation with single recommender’s performance. Empiric results show significant dependency between this correlation and the recommendation method at hand, as well as competitive results in terms of average correlation.This work was supported by the Spanish Ministry of Science and
Innovation (TIN2008-06566-C04-02), University Autónoma de Madrid and the Community
of Madrid (CCG10-UAM/TIC-5877