Bruno Bandeira Fernandes, Juarez A. P. Sacenti, and Roberto Willrich. 2017. Using Implicit Feedback for Neighbors Selection: Alleviating the Sparsity Problem in Collaborative Recommendation Systems. In Proceedings of the 23rd Brazilian Symposium on Multimedia and the Web, outubro 17, 2017, Gramado, Brasil. SBC, Porto Alegre, Brasil, 341-348.