1. Institute for Systems Theory and Automatic Control, University of Stuttgart, Pfaffenwaldring 9, 70550 Stuttgart, Germany
2. Department of Economics, University of Molise, via F. de Sanctis snc, 86100 Campobasso, Italy
3. Department of Psychology, Center for Logic, Language and Cognition, University of Torino, via Verdi 10, 10124 Torino, Italy