[1] Ton Duc Thang Univ, Inst Computat Sci, Div Computat Math & Engn, Ho Chi Minh City, Vietnam
[2] Ton Duc Thang Univ, Fac Math & Stat, Ho Chi Minh City, Vietnam
[3] Thai Nguyen Univ Econ & Business Adm, Thai Nguyen, Vietnam
[4] Chiang Mai Univ, Fac Econ, Ctr Excellence Econometr, Chiang Mai, Thailand