- 1 - Rationalizability of Choice Functions by Game Trees by Yongsheng Xu Department of Economics, Andrew Young School of Policy Studies Georgia State University, Atlanta, GA 30303 and Lin Zhou Department of Economics, WP Carey School of Business Arizona State University, Tempe, AZ 85287 First Version: January 30, 2004 This Version: May 3, 2004 Abstract: Collective choices are often cyclic and cannot be rationalized by a well-defined linear ordering. In this paper we identify conditions under which collective choices, potentially cyclic, can be rationalized by extensive games with perfect information. JEL Classification Numbers: C70, D70