Affiliation: | a University of Piemonte Orientale “A. Avogadro”, Department of Management Studies (SIT), Via Perrone 18, 28100 Novara, Italy b HERMES Research Center, Via Real Collegio 30, 10024 Moncalieri (TO), Italy c Ceris-CNR, Via Real Collegio 30, 10024 Moncalieri (TO), Italy d University of Torino, Department of Statistics and Applied Mathematics, Corso Unione Sovietica 218 bis, 10134 Torino (TO), Italy |