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