[1] Shanghai Univ Finance & Econ, Sch Finance, Shanghai, Peoples R China
[2] Anhui Univ Finance & Econ, Sch Int Trade & Econ, Bengbu, Peoples R China
[3] Nankai Univ, Sch Finance, Tianjin, Peoples R China
[4] Yunnan Normal Univ, Sch Econ & Management, Kunming, Peoples R China