1. Google Research, Google, San Francisco 1 , California 94105, USA
2. Department of Linguistics, University of California 2 , Davis, California 95616, USA
3. Department of Linguistics, Stanford University 3 , Stanford, California 94305, USA
4. Google Research, Google 4 , Seattle, Washington 98103, USA mdcohn@ucdavis.edu , zamengesha@stanford.edu , mlahav@google.com , cheldreth@google.com