Judgment aggregation and agenda manipulation

• 成果类型: Article
• 署名作者: Dietrich, Franz
• 署名单位: Paris School of Economics; Centre National de la Recherche Scientifique (CNRS)
• 刊物名称: GAMES AND ECONOMIC BEHAVIOR
• ISSN/ISSBN: 0899-8256
• DOI: 10.1016/j.geb.2016.01.001
• 发表日期: 2016
• 页码: 113-136
• 关键词: Judgment aggregation; Multiple issues; Description-sensitivity; Agenda manipulation; Impossibility theorems; Characterization theorems

摘要

When individual judgments ('yes' or 'no') on some propositions are aggregated into collective judgments, outcomes may be sensitive to the choice of propositions under consideration (the agenda). Such agenda-sensitivity opens the door to manipulation by agenda setters. I define three types of agenda-insensitivity ('basic', 'full', and 'focal') and for each type axiomatically characterize the aggregation procedures satisfying it. Two axioms turn out to be central for agenda-insensitivity: the familiar independence axiom, requiring propositionwise aggregation, and the axiom of implicit consensus preservation, requiring the respect of any (possibly implicit) consensus. As the paper's second contribution, I prove a new impossibility theorem whereby these two axioms imply dictatorial aggregation for almost all agendas. (C) 2016 Elsevier Inc. All rights reserved.