@incollection{NIPS2010_0779,
 title = {Collaborative Filtering in a Non-Uniform World: Learning  with the Weighted Trace Norm},
 author = {Ruslan Salakhutdinov and Nathan Srebro},
 booktitle = {Advances in Neural Information Processing Systems 23},
 editor = {J. Lafferty and C. K. I. Williams and J. Shawe-Taylor and R.S. Zemel and A. Culotta},
 pages = {2056--2064},
 year = {2010}
}