用预期效用理论单位三角形解释共同比率效应

摘要

本文提供一个新的视角来观察共同比率效应.这个悖论可以用期望效用理论和预期效用理论来解释.特别地,Machina(1987)在期望效用理论单位三角形比较一对彩票,共同比率效应形成一个悖论.在预期效用理论单位三角形中,效用函数无差异曲线保持平行,但是彩票的连线向内收敛,从而说明共同比率效应在预期效用理论可能是合理的,而不再是一个悖论.%This paper provides a new viewpoint to observe the contain ratio effect.This paradox can be explained from both the expected utility theory and the anticipated utility theory.In particular,we use the unit triangle approach in Machina (1987)to compare pairs of prospects.In the unit triangle diagram for the anticipated utility theory,the indifference curves maintain parallel,but lines of the compared prospect pairs fan in.Then this paradox is rational under the anticipated utility theory.