DivideandConquer Matrix Factorization 
Lester Mackey Ameet Talwalkar Michael I. Jordan 
DivideFactorCombine (DFC) is a parallel divideandconquer framework for
noisy matrix factorization problems, e.g., matrix completion and robust matrix
factorization. DFC divides a largescale matrix factorization task into smaller
subproblems, solves each subproblem in parallel using an arbitrary base matrix
factorization algorithm, and combines the subproblem solutions using techniques
from randomized matrix approximation.

Our experiments with collaborative filtering, video background modeling, and simulated data demonstrate the nearlinear to superlinear speedups attainable with this approach. Moreover, our analysis shows that DFC enjoys high probability recovery guarantees comparable to those of its base algorithm. More details about this work can be found in our paper: DivideandConquer Matrix Factorization (pdf, long version) L. Mackey, A. Talwalkar and M.I. Jordan Neural Information Processing Systems (NIPS) 2011 If you would like to experiment with DFC, you can download our compiled code (README, compiled.tar.gz) or our underlying matlab code (matlab.tar). 