1. Beijing Key Laboratory of Traffic Data Analysis and Mining, School of Computer and Information Technology, Beijing Jiaotong University, Beijing, China
2. Samueli School of Engineering, University of California at Los Angeles, Los Angeles, CA, USA
3. Institute for Infocomm Research, A*STAR, Fusionopolis, Singapore
4. School of Computer and Information Technology, Beijing Jiaotong University, Beijing, China