オガワ　タカユキ   OGAWA Takayuki
  小川　貴之
   所属   大阪経済大学  経済学部 経済学科
   職種   教授
発表年月日 2026/06/28
発表テーマ Endogenous Broker Choice, Investor Heterogeneity, and Stock Prices
会議名 日本ファイナンス学会 第34回大会
学会区分 全国学会
発表形式 口頭（一般）
単独共同区分 共同
開催地名 武蔵大学
開催期間 2026/06/28～2026/06/28
発表者・共同発表者 Takayuki Ogawa, Jun Sakamoto（発表者）, and Makoto Shimoshimizu
概要 This paper develops a general-equilibrium model in which investors with high and low initial stock endowments endogenously choose between brokers offering proportional and quadratic transaction-cost schedules. Because the quadratic schedule has a lower marginal cost for small trades whereas the proportional schedule becomes more attractive for large trades, broker choice is determined by investors’ portfolio-rebalancing needs. We show that, when stock-rich investors are a minority, a larger endowment gap, higher payoff risk, or greater efficiency of the proportional-cost broker induces a regime shift that lowers the stock price. Our analysis identifies endogenous broker choice as a novel mechanism through which investor heterogeneity and commission structures affect stock prices.
researchmap用URL https://nfa-net.jp/