First Author:   Pierre Dehez UCLouvain pierre.dehez@uclouvain.be   CORE-LIDAM, 34 Voie du Roman Pays Louvain-la-Neuve, 1348, Belgium   +32476819945(Phone) +32476819945(Fax) https://perso.uclouvain.be/pierre.dehez Second Author: Pier mario Pacini University of Pisa piermario.pacini@unipi.it   Dipartimento di Economia e Management, Via C. Ridolfi 10 Pisa, 56124, Italy   +393319390307(Phone)