First Author:   Stephane Goutte CEMOTEV, UVSQ, Paris-Saclay and VNU, International School, Hanoi stephane.goutte@uvsq.fr         Second Author: Imen Kouki ISG Tunis imen_kouki@yahoo.fr         Third Author: Ilyes Abid ISC Paris iabid@iscparis.com         Fourth Author: Khaled Guesmi CRECC, Paris School of Business kalloda_fr@yahoo.fr