文献紹介 Ma, H., King, I. and Lyu, R. M.: Effective missing data prediction for collaborative filtering, Proc. 30th Annual International ACM SIGIR Conference on Research and Development in Information Retrieval, pp. 39-46 (2007)  [in Japanese] Ma, H., King, I. and Lyu, R. M.: Effective missing data prediction for collaborative filtering, Proc. 30th Annual International ACM SIGIR Conference on Research and Development in Information Retrieval, pp.39-46, 2007  [in Japanese]