[1] Catholic Univ, Dept Math & Phys, Brescia, Italy
[2] SUNY Binghamton, Ctr Intelligent Syst, Binghamton, NY 13902 USA
[3] SUNY Binghamton, Thomas J Watson Sch Engn & Appl Sci, Dept Syst Sci & Ind Engn, Binghamton, NY 13902 USA
[4] Univ La Sapienza, ECONA, Interuniv Ctr Res Cognit Proc Nat & Artificial Sy, I-00185 Rome, Italy
[5] Univ La Sapienza, Dept Psychol, I-00185 Rome, Italy