1. Yosef Rinott is Professor, Federmann Center for the Study of Rationality and Department of Statistics, The Hebrew University of Jerusalem, Israel
2. Tomer Shoham is a graduate student, Federmann Center for the Study of Rationality and Department of Statistics, The Hebrew University of Jerusalem, Israel
3. Gil Kalai is Professor, Einstein Institute of Mathematics and Federmann Center for the Study of Rationality, The Hebrew University of Jerusalem, Israel and Efi Arazy School of Computer Science, IDC, Herzliya, Israel