[Wu, Wen-Ze] Cent China Normal Univ, Sch Econ & Business Adm, Wuhan 430079, Peoples R China.
[Hu, Zhiming] Zhejiang Gongshang Univ, Sch Math & Stat, Hangzhou 310018, Peoples R China.
[Wu, Wen-Ze] Natl Univ Singapore, NUS Business Sch, 21 Lower Kent Rd, Singapore S119077, Singapore.
[Qi, Qin] Tongji Univ, Sch Econ & Management, Shanghai 200092, Peoples R China.
[Zhang, Tao] Guangxi Univ Sci & Technol, Sch Sci, Liuzhou 545006, Peoples R China.