1. Rui Fan is at the Department of Economics; University of Illinois at Urbana-Champaign; Champaign, Illinois USA
2. Haiqi Li is at the College of Finance and Statistics; Hunan University; Changsha, Hunan China
3. Sung Y. Park is at the School of Economics; Chung-Ang University; 84 Heukseok-Ro, Dongjak-Gu, Seoul Korea