1. Laboratory of Public Economics, Faculty of Economics and Management, University of Abomey-Calavi, Abomey-Calavi, Benin
2. UFR Droit, sciences économique et politique, Site de DijonMaison de l’Université Esplanade Erasme BP 27877-21078 Dijon cedex France, Université de Bourgogne, Dijon, France
3. School of Economics, Southwestern University of Finance and Economics, Chengdu, People’s Republic of China