Odile Poulsen University of East Anglia   School of Economics University of East Anglia Norwich, NR4 7TJ United Kingdom   o.poulsen@uea.ac.uk   http://www.uea.ac.uk/%7Eec609/odileweb1.HTM           JEL Areas: C9 : Design of Experiments: General D5 : General Equilibrium and Disequilibrium: General