ナガオカ　ナルト   NAGAOKA Naruto   永岡　成人    所属   広島修道大学  経済科学部    職種   准教授
言語種別	英語
発行・発表の年月	2018/08
形態種別	学術論文
標題	Nonasymptotic Condorcet and Anti-Condorcet Jury Theorems under Strategic Voting
執筆形態	単著
掲載誌名	SSRN Working Paper Series
掲載区分	国外
著者・共著者	Naruto Nagaoka
概要	The nonasymptotic Condorcet jury theorem states that, under certain conditions, group decision-making by simple majority voting can decide more efficiently than single-person decision-making, in terms of having a higher probability of choosing the better alternative. Wit (1998) showed that the nonasymptotic Condorcet jury theorem holds under strategic voting in the basic model in which each member receives a binary signal. We examine the robustness of the nonasymptotic Condorcet jury theorem shown by Wit (1998) with respect to the assumptions of information structure. Our main result is that the nonasymptotic Condorcet jury theorem may not hold when the strongest signal that indicates a particular state is realized with probability less than 1/2. We provide a sufficient condition for this anti-Condorcet jury theorem with respect to the prior probability and the likelihoods of signals.