A taxonomy of non-dictatorial unidimensional domains

• 成果类型: Article
• 署名作者: Chatterji, Shurojit; Zeng, Huaxia
• 署名单位: Singapore Management University; Shanghai University of Finance & Economics
• 刊物名称: GAMES AND ECONOMIC BEHAVIOR
• ISSN/ISSBN: 0899-8256
• DOI: 10.1016/j.geb.2022.11.006
• 发表日期: 2023
• 页码: 228-269
• 关键词: Strategy-proofness; Invariance; Unidimensional domains; Semi-single-peaked preference; Semi-hybrid preference

摘要

Non-dictatorial preference domains allow the design of unanimous social choice functions (henceforth, rules) that are non-dictatorial and strategy-proof. On a class of preference domains called unidimensional domains, we show that the unique seconds property (introduced by Aswal et al., 2003) characterizes all non-dictatorial domains. Subsequently, we provide an exhaustive classification of all non-dictatorial, unidimensional domains, based on a simple property of two-voter rules called invariance. The domains constituting the classification are semi-single-peaked domains (introduced by Chatterji et al., 2013) and semi-hybrid domains (introduced here) which are two appropriate weakenings of single-peaked domains and shown to allow strategy-proof rules to depend on non-peak information of voters' preferences; the canonical strategy-proof rules for these domains are projection rules and hybrid rules respectively. As a refinement of the classification, single -peaked domains and hybrid domains emerge as the only unidimensional domains that force strategy-proof rules to be determined completely by preference peaks.(c) 2022 Elsevier Inc. All rights reserved.