[1] Univ Nis, Fac Sci & Math, Visegradska 33, Nish 18000, Serbia
[2] Natl & Kapodistrian Univ Athens, Dept Econ, Div Math Informat & Stat Econometr, Sofokleous 1 St, Athens 660041, Greece
[3] Siberian Fed Univ, Lab Hybrid Methods Modelling & Optimizat Complex S, Prosp Svobodny 79, Krasnoyarsk 660041, Russia
[4] Jiangnan Univ, Sch Business, Lihu Blvd, Wuxi 214122, Peoples R China
[5] Univ Oulu, Fac Informat Technol, Oulu, Finland