General equilibrium theory of monopolistic competition with income and productivity distributions and its applications

2022 Fiscal Year Final Research Report

• Project/Area Number: 17K03718
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Economic policy
• Research Institution: Nihon University
• Principal Investigator: MURATA Yasusada 日本大学, 経済学部, 教授 (40336508)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Keywords: 独占的競争 / 一般均衡理論 / 所得分布 / 生産性分布 / 利潤最大化価格

Outline of Final Research Achievements

I developed a general equilibrium model of monopolistic competition that takes into account both income and productivity distributions. In a general non-CES setting, the reservation price of a consumer for each variety depends on the price distribution (and thus the productivity distribution) of firms, as well as on his/her income. Therefore, firms with different productivity levels, which face consumers with different incomes, effectively choose the number of consumers who purchase their products by setting their own prices. I showed in this setting that the profit-maximizing price of each firm depends not only on its own productivity and the productivity distribution, but also on the income distribution.

Free Research Field

独占的競争

Academic Significance and Societal Importance of the Research Achievements

本研究で得られた企業の利潤最大化価格は，Behrens and Murata (2012)が導出した消費者の所得分布を考慮した価格とBehrens, Mion, Murata, and Suedekum (2014, 2017, 2020)が導出した企業の生産性分布を考慮した価格の性質を統合し，一般化している点において学術的に意義がある。また，従来の定量的貿易モデルや定量的空間経済モデルは，同一国内，同一都市内の全消費者が共通の物価に直面すると仮定してきたが，その前提は近年の実証研究により棄却されている。本研究は，それらの実証結果と整合的な新しい理論を提示しており，政策的にも意義があるだろう。