Computing a Nonnegative Matrix Factorization – Provably Ankur Moitra, IAS joint work with Sanjeev Arora, Rong Ge and Ravi Kannan June 20, 2012 AnkurMoitra (IAS) Provably June20,2012 m M n W m M = A inner−dimension n rank W m M = A inner−dimension n rank non−negative W m M = A inner−dimension n non−negative n o n − n e g a t i vraenk non−negative W m M = A inner−dimension n non−negative Information Retrieval documents: Information Retrieval documents: m M n Information Retrieval documents: W m M = A inner−dimension n Information Retrieval documents: "topics" W m M = A inner−dimension n