1. Department of Statistical Science, Levi Cases and CRIEP, University of Padua, Via Cesare Battisti 241, 35100 Padua, Italy
2. Department of Economics and CRIEP, University of Verona, Via Cantarane 24, 37129 Verona, Italy
3. Department of Economics and Management and CRIEP, University of Padua, Via del Santo 33, 35123 Padua, Italy