About the Authors

Liang Zhao

liangz8@vt.edu

Affiliation Department of Computer Science, Virginia Tech, Falls Church, Virginia, United States of America

Feng Chen

Affiliation Department of Computer Science, University at Albany-SUNY, Albany, New York, United States of America

Jing Dai

Affiliation Google, New York City, New York, United States of America

Ting Hua

Affiliation Department of Computer Science, Virginia Tech, Falls Church, Virginia, United States of America

Chang-Tien Lu

Affiliation Department of Computer Science, Virginia Tech, Falls Church, Virginia, United States of America

Naren Ramakrishnan

Affiliation Department of Computer Science, Virginia Tech, Falls Church, Virginia, United States of America

Competing Interests

Co-author Jing Dai is an employee of Google Inc. This does not alter the authors' adherence to all the PLOS ONE policies on sharing data and materials.

Author Contributions

Conceived and designed the experiments: LZ FC. Performed the experiments: LZ TH. Analyzed the data: LZ. Contributed reagents/materials/analysis tools: LZ TH JD. Wrote the paper: LZ FC. Proofread the manuscript: LZ CTL FC JD NR.