Affiliation: | (1) Microsoft Research Silicon Valley, 1065 La Avenida, Mountain View, CA, 94043, U.S.A.;(2) Department of Computer Science, University of Massachussets Amherst, 140 Governors Drive, Amherst, MA, 01003, U.S.A.;(3) Electrical Engineering and Computer Science Department, University of California Berkeley, Berkeley, CA, 94720, U.S.A.;(4) Bell-Labs, Alcatel-Lucent, 600 Mountain Avenue, Murray Hill, NJ, 07974, U.S.A. |