有限⾃制⼒的表現定理

Abstract

本⽂旨在建構⼀個表現定理，使個體可於數個集合中先做選擇，接著在此集合中選出單⼀物件。此定理考慮擁有「偏好承諾」此⼀特性的偏好關係，⽽這種偏好⾸先由Gul and Pesendorfer (2001) 所提出。有別於⽂獻中假設個體擁有無限意志⼒抑或毫無意志⼒，本⽂的表現定理則允許個體擁有有限的意志⼒。我們與⽂獻的主要差異在於我們放寬了Gul and Pesendorfer (2001) ⽂獻中的定理三之獨⽴公設並且保留其餘的公設。此外，在我們的模型中，若個體的意志⼒不⾜以抵抗誘惑，則會因意志⼒的限制⽽只能選取較低事前效⽤的選項；反之，成功抵抗誘惑的個體會保持與⽂獻中相同的⾏為。

This dissertation constructs a representation theorem for individual choice among sets of alternatives, from which the individual will later choose a single object. In particular, it concerns preference relations on sets of alternatives which satisfy “preference for commitment,” first characterized by Gul and Pesendorfer (2001). Instead of assuming the individual either having unlimited willpower or none at all, we consider the same model as Gul and Pesendorfer but with limited willpower to resist temptation. We relax the Independence Axiom and keep the rest axioms of their Theorem 3 in our characterization. Agents with insufficient willpower to resist temptations are bound to choose an option with lower ex ante utility while the behaviors of agents who resist temptations remain unchanged.