FTITI ZIED Hight Business institute of Tunsia ISG- FIESTA laboratory and UAQUAP Laboratory   zftitio@gmail.com , Lyon 69120 France   zftitio@gmail.com   http://ideas.repec.org/e/pft1.html           JEL Areas: E5 : Monetary Policy, Central Banking, and the Supply of Money and Credit: General C0 : Mathematical and Quantitative Methods: General