0.Reference
美团FFM: https://tech.meituan.com/2016/03/03/deep-understanding-of-ffm-principles-and-practices.html CMUpdf: http://www.cs.cmu.edu/~wcohen/10-605/2015-guest-lecture/FM.pdf CSDN: http://www.52caml.com/head_first_ml/ml-chapter9-factorization-fam…