First Author:   Udo Ebert University of Oldenburg ebert@uni-oldenburg.de   Department of Economics, University of Oldenburg Oldenburg, D-26111, Germany   +49 441 798-4113(Phone) +49 441 798-4113(Fax) Second Author: Patrick Moyes CNRS, IDEP, and GRAPE, Université Montesquieu Bordeaux IV moyes@montesquieu.u-bordeaux.fr   CNRS, IDEP, and GRAPE, Université Montesquieu Bordeaux IV, Avenue Léon Duguit Pessac, F-33608, France   +33 5.56.84.29.05(Phone) +33 5.56.84.29.64(Fax)