Critiques for the efficiency of majority voting by a large electorate

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K13644
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 07010:Economic theory-related
• Research Institution: Hokusei Gakuen University
• Principal Investigator: Tajika Tomoya 北星学園大学, 経済学部, 准教授 (70801562)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: 陪審定理

Outline of Final Research Achievements

Consider a problem having correct and incorrect answers. It is known that if the alternatives are "two choices," people "independently" receive information about the correct answer, and there are an infinite number of people, the probability that the majority vote will be wrong converges to zero.
The following environment was introduced in this study. The problem can be either a "straightforward question" or a "tricky question". For the straightforward question, the accuracy of the information people receive is greater than 1/2; for the trick question, the accuracy of the information is less than 1/2.
Under this setting, we show that the probability that the majority vote can be wrong can converge to one. Furthermore, by applying the method to a communication game and sequential decision problems, we showed that inefficient decision making can occur even in an environment where there is no conflict of interest.

Free Research Field

ゲーム理論

Academic Significance and Societal Importance of the Research Achievements

本研究の主な貢献はひっかけ問題の可能性を導入することで、通常問題が起きないと考えられている人々に利害の対立がない環境においても非効率な意思決定が発生しうることを示したことである。こういった環境は利益追求を目的とする企業における会議や医療の現場において存在しうる。こういった環境においてさえも意思決定や情報伝達に問題が発生していることが知られている。本研究の意義はこういった現象に説明と解決策を与えるという意義がある。