1. Department of Information Management; Peking University; No. 5, Yiheyuan Road Haidian District Beijing 100871 China
2. Department of Information Systems and Operations Management; Warrington College of Business Administration; University of Florida; Gainesville Florida 32611-7169 USA
3. School of Accounting and Finance; Faculty of Business; The Hong Kong Polytechnic University; Li Ka Shing Tower Hung Hom Hong Kong