Robuta

https://research.ibm.com/publications/contextual-collaborative-filtering-via-hierarchical-matrix-factorization Contextual collaborative filtering via hierarchical matrix factorization for SDM 2012 - IBM Research Contextual collaborative filtering via hierarchical matrix factorization for SDM 2012 by Erheng Zhong et al. collaborative filteringhierarchical matrixibm researchcontextualvia