1. School of Computer Science and Engineering, Nanyang Technological University, Singapore
2. LILY Research Centre, Nanyang Technological University, Singapore
3. Alibaba-NTU Singapore Joint Research Institute, Singapore
4. Department of Electrical and Computer Engineering, The University of British Columbia, Vancouver, BC, Canada
5. School of Computer Science, University of Massachusetts Amherst, Amherst, MA, USA
6. Department of Computer Science and Engineering, Hong Kong University of Science and Technology, Hong Kong