1. Preference An (acceptablealternatives set (or a consumption set)Xc界 A(weak) preference relation"%: a binary relationship on x, for any x,yEX, x% ymeans x is at least as good as y A strict preference“x xxyex% y, but not y %x 。 An indifference relation“~ xxyex% y, and y %x lectures for Chu Kechen Honors Collegelecture5 for Chu Kechen Honors College 1.Preference ➢ An (acceptable) alternatives set (or a consumption set ) ⚫ A (weak) preference relation“ ”: a binary relationship on X, for any , means” x is at least as good as y”. ⚫ A strict preference “ ”: ⚫ An indifference relation “ ”: k X  + % x y,  X x y % x y x y y x  % % ,but not x y x y y x  % % ,and