Updated on 2023/12/05

写真a

 
KUBOTA, So
 
Affiliation
Faculty of Political Science and Economics, School of Political Science and Economics
Job title
Associate Professor(tenure-track)
Degree
Ph.D ( Princeton University (USA) )
修士（経済学） ( 東京大学 )
Homepage URL
https://sites.google.com/site/gkubotaso/

Research Experience

  • 2019.09
    -
    Now

    Waseda University   School of Political Science and Economics   Associate Professor (Tenure-Track)

  • 2018.08
    -
    Now

    Hitotsubashi University   Hitotsubashi Institute for Advanced Study   Specially Appointed Assistant Professor

  • 2017.09
    -
    2018.07

    The University of Tokyo

Education Background

  • 2011.09
    -
    2017.08

    Princeton University   Graduate School, Division of Economics  

  • 2009.04
    -
    2011.03

    The University of Tokyo   Graduate School, Division of Economics  

  • 2005.04
    -
    2009.03

    Hitotsubashi University   Faculty of Economics  

Professional Memberships

  • 　
    　
    　

    American Economic Association

  • 　
    　
    　

    日本経済学会

Research Areas

  • Economic policy / Economic policy

Research Interests

  • Economics

Awards

  • 中島記念国際交流財団奨学金

    2011.08   公益財団法人 中島記念国際交流財団  

 

Papers

  • The macroeconomics of COVID-19 exit strategy: the case of Japan

    So Kubota

    The Japanese Economic Review   72 ( 4 ) 651 - 682  2021.10

    　View Summary

    <jats:title>Abstract</jats:title><jats:p>In this paper, I use a simple SIR Macro model to examine Japan’s soft lockdown policies in 2021 under the COVID-19 crisis. As real-time research, this paper consists of two parts written during two different research periods. The first part, which was originally reported in February 2021, studies the Japan’s second soft lockdown policy (state of emergency declaration) from January to March 2021. After the model is calibrated using 2020 data, the results show that a long enough lockdown can avoid future lockdowns, improving both the infection and the economy. In addition, I propose the ICU targeting policy, which keeps the number of severe patients at a constant level, mimicking the monetary policy’s inflation targeting. The model’s prediction is evaluated from an ex-post perspective in the second part, written in July 2021. I find that the model broadly captures the realized consequences of the second soft lockdown and the subsequent paths. Furthermore, the simulation is projected to the end of the pandemic under a revised scenario, incorporating the proliferation of COVID-19 variants. Finally, I discuss the effectiveness of the inverse lockdown (economic stimulus) policy in the fall of 2021 under the dynamic infection externality.</jats:p>

    DOI

    Scopus

    9
    Citation
    (Scopus)

  • Consumption responses to COVID-19 payments: Evidence from a natural experiment and bank account data

    So Kubota, Koichiro Onishi, Yuta Toyama

    Journal of Economic Behavior & Organization    2021.08

    DOI

    Scopus

    27
    Citation
    (Scopus)

  • Who spent their COVID-19 stimulus payment? Evidence from personal finance software in Japan

    Michiru Kaneda, So Kubota, Satoshi Tanaka

    The Japanese Economic Review   72 ( 3 ) 409 - 437  2021.07

    　View Summary

    <jats:title>Abstract</jats:title><jats:p>In response to the COVID-19 crisis, governments worldwide have been formulating and implementing different strategies to mitigate its social and economic impacts. We study the household consumption responses to Japan’s COVID-19 unconditional cash transfer program. Owing to frequent delays in local governments’ administrative procedures, the timing of the payment to households varied unexpectedly. Using this natural experiment, we analyze households’ consumption responses to cash transfers using high-frequency data from personal finance management software that links detailed information on expenditure, income, and wealth. We construct three consumption measures: one captures the baseline marginal propensity to consume (MPC), and the other two are for the lower and the upper bound of MPC. Additionally, we explore heterogeneity in MPCs by household income, wealth, and population characteristics, as well as consumption categories. Our results show that households exhibit immediate and non-negligible positive responses in household expenditure. There is significant heterogeneity depending on various household characteristics, with liquidity constraint status being the most crucial factor, in line with the standard consumption theory. Additionally, this study provides policymakers with insights regarding targeted cash transfer programs, conditioning on labor income, and liquidity constraints.</jats:p>

    DOI

    Scopus

    13
    Citation
    (Scopus)

  • 新型コロナウイルス危機のマクロ経済分析

    So Kubota

    医療経済研究    2021

    DOI

  • Real Indeterminacy of Stationary Monetary Equilibria in Centralized Economies

    Kazuya Kamiya, So Kubota, Kayuna Nakajima

    Japanese Economic Review   68 ( 4 ) 497 - 520  2017.12  [Refereed]

    　View Summary

    We show that real indeterminacy of stationary equilibria, by which the set of stationary equilibria is a continuum and the real allocation varies among equilibria, may arise in some general equilibrium models with fiat money. The conditions under which such equilibria arise are: (i) each household optimally saves a constant amount of money
    and (ii) at least two households face different budget constraints. We present various models, including a decentralized money search model and a centralized model with a monopoly firm, to explain how these conditions lead to real indeterminacy. Finally, we present a policy that uniquely implements any desirable outcome.

    DOI

    Scopus

Presentations

  • Culture, Gender, and Structural Transformation: A Case of Turkey

    久保田 荘

    マクロ経済学研究会 

    Presentation date： 2019.12

  • The U.S. Child-Care Crisis: Facts, Causes, and Policies

    久保田 荘

    青山学院大学経済研究所ワークショップ 

    Presentation date： 2019.11

  • Child care costs and stagnating female labor force preparation in the US

    久保田荘

    明星大学MUETEIワークショップ 

    Presentation date： 2019.09

  • Culture, Gender, and Structural Transformation: A Case of Turkey

    So Kubota

    Presentation date： 2019.05

  • Child care costs and stagnating female labor force preparation in the US

    Presentation date： 2019.04

  • A Search and Bargaining Model of Non-degenerate Distributions of Money Holdings

    久保田 荘

    Presentation date： 2019.01

  • Child Care Costs and Stagnating Female Labor Force Participation in the US

    久保田 荘  [Invited]

    Summer Workshop on Economic Theory 

    Presentation date： 2018.09

  • Child care costs and stagnating female labor force participation in the U.S.

    久保田 荘

    慶應義塾大学応用経済学・マクロ経済学（共催）ワークショップ 

    Presentation date： 2018.06

  • Culture and Labor Supply: Decline in Female Market Work in Turkey

    久保田 荘

    OSIPP Economics Brownbag Seminar 

    Presentation date： 2018.05

  • Indeterminacy in Search Theory of Money: Bilateral vs. Multilateral Trades

    So Kubota

    Society for Nonlinear Dynamics and Econometrics 

    Presentation date： 2018.02

  • Child Care Costs and Stagnating Female Labor Force Participation in the US

    So Kubota

    GRIPS-KEIO Macroeconomic and Policies Workshop 

    Presentation date： 2018.02

  • Culture and Labor Supply: Decline in Female Market Work in Turkey

    久保田 荘

    Economic Theory and Policy Workshop 

    Presentation date： 2018.02

  • Child Care Costs and Stagnating Female Labor Force Participation in the US

    So Kubota

    GRIPS-U Tokyo Workshop 

    Presentation date： 2017.12

  • Indeterminacy in Search Theory of Money: Bilateral vs. Multilateral Trades

    久保田 荘

    東京大学ミクロ経済学ワークショップ 

    Presentation date： 2017.11

  • Child Care Costs and Stagnating Female Labor Force Participation in the US

    久保田 荘

    一橋大学マクロ金融ワークショップ 

    Presentation date： 2017.10

  • Child Care Costs and Stagnating Female Labor Force Participation in the US

    So Kubota  [Invited]

    Bogazici University 

    Presentation date： 2017.02

  • Child Care Costs and Stagnating Female Labor Force Participation in the US

    So Kubota  [Invited]

    Istanbul Technical University 

    Presentation date： 2017.02

  • Child Care Costs and Stagnating Female Labor Force Participation in the US

    久保田 荘  [Invited]

    Koc University 

    Presentation date： 2017.02

  • Child Care Costs and Stagnating Female Labor Force Participation in the US

    久保田 荘  [Invited]

    東京大学マクロ経済学ワークショップ 

    Presentation date： 2017.02

  • Child Care Costs and Stagnating Female Labor Force Participation in the US

    So Kubota  [Invited]

    Sungkyunkwan University 

    Presentation date： 2017.02

  • Indeterminacy in Search Theory of Money: Bilateral vs. Multilateral Trades

    So Kubota

    Summer Workshop on Money, Banking, Payments, and Finance 

    Presentation date： 2014.08

  • Indeterminacy in Search Theory of Money: Bilateral vs. Multilateral Trades

    久保田 荘

    Spring Meeting of Japanese Economic Association 

    Presentation date： 2011.06

  • Indeterminacy in Search Theory of Money: Bilateral vs. Multilateral Trades

    久保田 荘  [Invited]

    Search Theory Workshop 

    Presentation date： 2011.05

  • Real Indeterminacy of Stationary Monetary Equilibria in Centralized Economies

    So Kubota  [Invited]

    International Young Economist Conference 

    Presentation date： 2010.10

  • Real Indeterminacy of Stationary Monetary Equilibria in Centralized Economies

    久保田 荘  [Invited]

    Summer Workshop on Economic Theory 

    Presentation date： 2010.08

  • Real Indeterminacy of Stationary Monetary Equilibria in Centralized Economies

    久保田 荘  [Invited]

    数理経済学研究会 

    Presentation date： 2010.07

  • Decentralized Trading and the Superneutrality of Money

    久保田 荘

    Search Theory Workshop 

    Presentation date： 2009.06

▼display all

Research Projects

  • Theoretical and empirical studies on containment and economic policies under COVID-19 recession

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research Grant-in-Aid for Early-Career Scientists

    Project Year :

    2022.04
    -
    2024.03
     

  • 貨幣取引の基礎付けと新しい金融政策モデルの構築

    公益財団法人東京海上各務記念財団  学術の研究に対する助成

    Project Year :

    2022.11
    -
    　
     

  • 金融ビッグデータを利用した１０万円特別定額給付金の政策評価

    公益財団法人日本法制学会  財政・金融・金融法制研究基金研究助成金募集要項

    Project Year :

    2021.04
    -
    2022.07
     

  • Quantitative macroeconomic study on the U.S. childcare market.

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research Grant-in-Aid for Early-Career Scientists

    Project Year :

    2019.04
    -
    2022.03
     

    Kubota So

    　View Summary

    In this project, I have mainly studied the macroeconomic approach on family economics.
    My main topic is the long-term trend of the child care market in the United States. I first find a sharp increase in the child care price in the late 1990s. I show that a massive expansion of federal and state means-tested child care subsidies, which were intended to stimulate the market, instead crowded out child care supply. A simple calibrated equilibrium model captures these effects. I also extended it to a rich life-cycle model and incorporate other taxes and benefits.
    Given the COVID-19 recession hit worldwide, I also started a new project about household consumption behaviors. In particular, I study the marginal propensity of consumption (MPC) to Japan’s COVID-19 unconditional cash transfer program. I used a natural experiment about the timing of transfer caused by administrative procedures. Interestingly, the MPC is almost homogeneous over family size and family type.

  • 貨幣保有の異質性を含むサーチモデルと金融政策

    全国銀行学術研究振興財団  研究活動に対する助成

    Project Year :

    2019.09
    -
    2021.09
     

  • 貨幣の存在の経済理論的基礎付

    日本学術振興会  科学研究費助成事業

    Project Year :

    2011.04
    -
    2011.08
     

▼display all

 

Syllabus

▼display all

Teaching Experience

  • Macroeconomics for Public Policy

    東京大学公共政策大学院  

  • Principles of Macroeconomics

    東京大学公共政策大学院  

 

Sub-affiliation

  • Faculty of Social Sciences   Graduate School of Social Sciences

Internal Special Research Projects

  • サーチモデルと金融政策の再分配効果

    2022   神谷和也

    　View Summary

    本研究については完了し、論文をTheoretical Economics誌に投稿した。学会については、2nd Australasian Search and Matching Workshop (Australia, Sydney, UNSW)にて発表予定である。また、本研究のための追加外部資金として、東京海上各務記念財団からも支援を受けた。今後は、本研究のモデルを応用し、Rate of return dominance puzzleの解決に取り組む予定である。

  • 新型コロナウイルス危機のマクロ経済分析

    2021   遠山祐太, 大西宏一郎, 田中聡史, 兼田充

    　View Summary

    本課題について、私は2020年に交付された10万円特別定額給付金の政策効果検証、及び感染症と経済の融合モデルを用いた緊急事態宣言の分析を行った。前者について、みずほ銀行口座データ、およびマネーフォワード社の家計簿アプリのデータを用いて、給付金支給後の人々の消費行動変化を測定した。その結果、10万円のうち平均で2,3万円程度が消費されたこと、また流動性制約の影響が大きかったことなどが分かった。後者については、世界的に急ピッチで開発が行われた、感染症疫学モデルとマクロ経済モデルを融合した疫学マクロモデルを用いて、緊急事態宣言の感染・経済効果の政策シナリオ分析を行い、新型コロナウイルス感染症対策分科会へ結果を提出した。

  • 女性雇用の国際比較分析

    2020   松田

    　View Summary

    本研究では主にアメリカの保育市場と女性労働の関係に取り組んだ。アメリカの保育市場について、クリントン政権下でChild Care Development Fundと呼ばれる低所得者向けの育児支援補助が拡大された。これは本来女性の労働参加を促進するが、逆にfamily daycare homeと呼ばれる個人経営の保育園を自宅で営む保育士で、かつ彼女たち自身もワーキングマザーである人々の職業選択に影響を与えたという仮説を検証した。IPUMS census個票用いて、そのような保育士兼ワーキングマザーの地域別偏在を調べた。その結果、確かに保育士兼ワーキングマザーの多い地域ほど保育園の価格が上昇したことが確認された。

  • 貨幣保有の異質性を含むサーチモデルと金融政策

    2019   神谷和也

    　View Summary

    本研究では、貨幣の流通を基礎付けた上で金融政策の効果を考察する貨幣サーチ理論について研究を行った。この分野では端緒となったkiyotaki-Mooreモデルから始まって、それに貨幣数量を導入する形で分析が進められた。貨幣保有の異質性により分析が困難になり、また均衡が無限に存在するなどの問題が知られている。応用分野ではLagos-Wrightなど人口的な構造によりこの問題を回避しているが、私は神戸大学の神谷和也と共同で、貨幣保有についての異質性やナッシュ交渉のよる取引などモデルの基礎的な要素を持ちつつも、簡潔に解くことができるモデルを開発した。均衡の性質を調べ、また金融政策が貨幣取引における買い手と売り手の交渉力の移転によって効果を持ちうることを示した。