1. Civil and Environmental Engineering Department, University of California, Berkeley, Berkeley, California 94720;
2. Naveen Jindal School of Management, The University of Texas at Dallas, Richardson, Texas 75080;
3. W. P. Carey School of Business, Arizona State University, Tempe, Arizona 85287;
4. Chinese University of Hong Kong Business School, The Chinese University of Hong Kong, Hong Kong, China;
5. Faculty of Engineering and Faculty of Business and Economics, University of Hong Kong, Hong Kong, China