Updated on 2025/05/21

写真a

 
Junichiro Wada
 
Organization
Graduate School of International Management Department of International Management Professor
School of Economics and Business Administration Department of Economics and Business Administration
School of Economics and Business Administration Dean
Title
Professor
Contact information
メールアドレス
Homepage
http://juniwada.in.coocan.jp/
Profile

一橋大学経済学部、同大学院経済学研究科修士課程を経て、ロータリー財団の奨学金により米国メリーランド大学へ留学。Ph.D. 1997年度開設の横浜市立大学大学院経済学研究科博士後期課程設置に当たっての教員審査においてＤマル合判定。「ナッシュ積（ナッシュ社会的厚生関数）に基づいた一票の不平等の研究」で選挙学会賞、A divisor apportionment method based on the Kolm-Atkinson social welfare function and generalized entropyで公共政策学会論説賞、「定数配分と基準人口」で選挙学会賞を受賞。

External link

Degree

  • Doctor of Philosophy ( 1995.1   University of Maryland )

  • Master of Arts in Economics ( 1987.3   Hitotsubashi University )

Research Interests

  • electoral system

  • apportionment

  • districting

  • turnout ratio

Research Areas

  • Humanities & Social Sciences / Politics  / Mathematical Political Science

  • Humanities & Social Sciences / Public economics and labor economics  / Public Choice

Professional Memberships

  • The Japanese Society for Quantitative Political Science

    　 More details

  • JAPANESE POLITICAL SCIENCE ASSOCIATION

    　 More details

  • 統計研究会財政金融研究委員会

    　 More details

  • Public Policy Studies Association, Japan

    　 More details

  • THE JAPAN PUBLIC CHOICE SOCIETY

    　 More details

  • JAPANESE ECONOMIC ASSOCIATION

    　 More details

  • THE JAPAN INSTITUTE OF PUBLIC FINANCE

    　 More details

  • JAPANESE ASSOCIATION OF ELECTORAL STUDIES

    　 More details

  • Public Choice Society

    　 More details

▼display all

Committee Memberships

  • 公共選択学会   幹事：理事：専務理事：会長。プログラム委員。プログラム委員長・大会実行委員長  

       

    　 More details

    Committee type：Academic society

    公共選択学会

    researchmap

  • 日本選挙学会   編集委員; 紀要編集委員長; 理事; 査読副委員長; 委員長  

       

    　 More details

    Committee type：Academic society

    日本選挙学会

    researchmap

  • The Japanese Society for Quantitative Political Science   Organizer; Chair of the Program Committee  

       

    　 More details

    Committee type：Academic society

    researchmap

  • 統計研究会財政金融研究委員会   財政班幹事  

       

    　 More details

    Committee type：Academic society

    統計研究会財政金融研究委員会

    researchmap

  • 公共政策学会   理事選考委員; 学会賞選考委員; 編集委員; 企画委員; 学術委員  

       

    　 More details

    Committee type：Academic society

    公共政策学会

    researchmap

Papers

  • A unified approach to measuring unequal representation Reviewed

    Junichiro Wada, Yuta Kamahara

    Public Choice   201   287 - 308   2024.4

    　More details

    Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1007/s11127-024-01159-z

    researchmap

  • Malapportionment in space and time: Decompose it! Reviewed

    Yuta Kamahara, Junichiro Wada, Yuko Kasuya

    Electoral Studies   71   102301 - 102301   2021.6

    　More details

    Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

    DOI： 10.1016/j.electstud.2021.102301

    researchmap

  • Studying malapportionment using α-divergence Reviewed

    Junichiro Wada, Yuta Kamahara

    Mathematical Social Sciences   93   77 - 89   2018.5

    　More details

    Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Elsevier B.V.  

    This study shows the superiority of α-divergence over Samuels and Snyder's MAL index for 73 countries, using Samuels and Snyder's database. As α-divergence rests on a philosophical basis, that is, a microfoundation, we calculate the degree of malapportionment in terms of each philosophy of apportionment and/or presume the apportionment principles of countries. Furthermore, we decompose the malapportionment factors into the existence of special districts, apportionment to the states, and districting. Therefore, measuring the degree of malapportionment must be based not on distance, but on α-divergence.

    DOI： 10.1016/j.mathsocsci.2018.02.003

    Scopus

    researchmap

  • 一票の平等―個人還元主義の貫徹― Invited

    和田淳一郎

    オペレーションズ・リサーチ   62 ( 10 )   662 - 670   2017.10

    　More details

    Language：Japanese   Publishing type：Research paper (scientific journal)  

    One-Man One-Vote, One-Vote One-Value の言葉に込められた個人還元主義に基づく定数配分が追求される．一般的な社会的厚生関数に対応する，人口分布から議員数分布までの擬距離 (divergence) である α-divergenceの最小化により，Adams 方式（1 + D’Hondt 方式）から Jefferson 方式（D’Hondt 方式）に至る Stolarsky 平均を閾値にする一連の除数方式が導かれ，論争の続く Hill 方式（アメリカ下院方式，閾値幾何平均方式）と Webster 方式（Sainte–Lagu¨e 方式，閾値算術平均方式）の間に落ち，Nash 型社会的厚生関数に対応する，人口割合から議員割合までの擬距でもある Kullback–Leibler divergence の最小化により導出される閾値対数平均方式の採用が主張される．

    researchmap

  • APPORTIONMENT BEHIND THE VEIL OF UNCERTAINTY Reviewed

    Junichiro Wada

    JAPANESE ECONOMIC REVIEW   67 ( 3 )   348 - 360   2016.9

    　More details

    Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-BLACKWELL  

    Apportionment of representatives is a basic rule of everyday politics. By definition, this basic rule is a constitutional stage problem and should be decided behind the veil of uncertainty. To bring apportionment closer to quotas, we introduce f-divergence for utilitarianism and Bregman divergence for consistent optimization. Even in our less restricted condition, we find that we must use alpha-divergence for optimization and show that the minimization of alpha-divergence induces the same divisor methods that correspond to the maximization of the Kolm-Atkinson social welfare function (or the expected utility function), which is bounded by constant relative risk aversion.

    DOI： 10.1111/jere.12093

    Web of Science

    J-GLOBAL

    researchmap

  • A divisor apportionment method based on the Kolm-Atkinson social welfare function and generalized entropy Reviewed

    Junichiro Wada

    MATHEMATICAL SOCIAL SCIENCES   63 ( 3 )   243 - 247   2012.5

    　More details

    Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

    This paper links Stolarsky mean apportionment methods, which include the US House of Representatives, the Saint-Lague, and the d'Hondt methods, to Kolm-Atkinson social welfare maximization and to generalized entropy minimization. Within this class, the logarithmic mean apportionment method is the most unbiased one that assigns at least one seat to each state. (c) 2012 Elsevier B.V. All rights reserved.

    DOI： 10.1016/j.mathsocsci.2012.02.002

    Web of Science

    researchmap

  • EVALUATING THE UNFAIRNESS OF REPRESENTATION WITH THE NASH SOCIAL WELFARE FUNCTION Reviewed

    Junichiro Wada

    JOURNAL OF THEORETICAL POLITICS   22 ( 4 )   445 - 467   2010.10

    　More details

    Language：English   Publishing type：Research paper (scientific journal)   Publisher：SAGE PUBLICATIONS LTD  

    Using the Nash product (Nash Social Welfare Function) as a micro foundation, we create a decomposable index to evaluate the unfairness of representation in electoral districts. Using this index, we decompose the factors of such unfairness into apportionment and districting. We explore the situations of New Zealand, the United States, Australia, the United Kingdom, Japan, and Canada. We then provide an integer solution that minimizes the index of the apportionment, which can be obtained by the divisor method (Balinski and Young, 1982) using a logarithmic mean.

    DOI： 10.1177/0951629810375643

    Web of Science

    researchmap

  • Elections in Japan Invited

    Junichiro WADA

    Harvard Asia Pacific Review   6 ( 2 )   2002.12

    　More details

    Language：English  

    researchmap

  • Apportionment and the Population Figure Reviewed

    Yuta KAMAHARA, Junichiro WADA

    Japanese Journal of Electoral Studies   39 ( 1 )   107 - 121   2023.12

    　More details

  • 無投票選挙と公共工事入札談合 ――寄り合い社会がもたらすもの――

    田辺美冬, 鞠重鎬, 和田淳一郎

    横浜市立大学論叢   72 ( 2・3 )   57 - 75   2021.3

    　More details

  • Optimal Combined Districts in the House of Councilors Reviewed

    Keisuke HOTTA, Toshio NEMOTO, Junichiro WADA

    JAPANESE JOURNAL OF ELECTORAL STUDIES   35 ( 2 )   86 - 102   2019.12

    　More details

    Language：Japanese   Publishing type：Research paper (scientific journal)  

    researchmap

  • 投票参加を考える～経済学的観点から Invited

    和田淳一郎

    Voters   41   2017.12

    　More details

    Language：Japanese  

    researchmap

  • Historical Transition of Malapportionment in Japan's House of Representatives : What Does α-Divergence Tell Us? Invited

    ( 67 )   104 - 121   2017.1

    　More details

    Authorship：Lead author,　Corresponding author   Language：Japanese   Publishing type：Research paper (scientific journal)  

    CiNii Books

    researchmap

  • Distortions in the Japanese Election System Invited

    ( 60 )   79 - 98   2013

    　More details

    Language：Japanese  

    CiNii Books

    researchmap

  • Apportionment and Districting Invited

    WADA Junichiro

    Japanese Journal of Electoral Studies   28 ( 2 )   26 - 39   2012.12

    　More details

    Language：Japanese   Publisher：Japanese Association of Electoral Studies  

    The current agenda of reapportionment (summer 2012), in which the less populous prefecture (Osaka) has more representatives than the more populous one (Kanagawa), is unfair. Under an unequal representation, the welfare of people with more representatives is worse than it is under a fair representation. Therefore, this agenda is not only inequitable but also inefficient. Using the Nash Social Welfare Function, we create a decomposable index to evaluate the unfairness of representation in electoral districts. We then provide some apportionments, which can be obtained by the divisor methods, by minimizing the objective function made from the Atkinson Social Welfare Function, which includes the Rawlsian, Nash, and Benthamian Social Welfare Functions. We also indicate the problem of man-made districting. We conclude the essay with an indication of the problems of proportional representation and geographic districting.

    DOI： 10.14854/jaes.28.2_26

    researchmap

    Other Link： https://www.jstage.jst.go.jp/article/jaes/28/2/28_26/_pdf/-char/ja

  • Using a Nash Product (Nash Social Welfare Function) to Evaluate the Unfairness in Electoral Apportionment and Districting Reviewed

    WADA Junichiro

    Japanese Journal of Electoral Studies   26 ( 2 )   131 - 138   2010.12

    　More details

    Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japanese Association of Electoral Studies  

    Using a Nash product (Nash social welfare function) as a micro foundation, we derive a decomposable index to evaluate unfairness of representation in electoral districts. With this index, we decompose the factors of such unfairness into apportionment and districting. Further, using census data, we explore the situations surrounding Japanese electoral reforms after World War II.

    DOI： 10.14854/jaes.26.2_131

    CiNii Books

    researchmap

    Other Link： https://www.jstage.jst.go.jp/article/jaes/26/2/26_131/_pdf/-char/ja

  • 選挙の制度設計 Invited

    和田淳一郎

    経済セミナー   651   2009.12

    　More details

    Language：Japanese   Publishing type：Research paper (scientific journal)  

    researchmap

  • アメリカの選挙・日本の選挙 (特集=ゲーム理論--非合理な世界の合理性) Invited

    和田 淳一郎

    現代思想   36 ( 10 )   142 - 153   2008.8

    　More details

    Language：Japanese   Publisher：青土社  

    CiNii Books

    researchmap

  • GISを活用した投票率の分析 Reviewed

    坂口 利裕, 和田 淳一郎

    公共選択の研究   2007 ( 48 )   18 - 35   2007

    　More details

    Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：JAPAN PUBLIC CHOICE SOCIETY  

    researchmap

  • The effects of increasing early polling stations in Yokohama Reviewed

    Review of electoral studies   7 ( 7 )   27 - 35   2006.11

    　More details

    Language：Japanese  

    CiNii Books

    researchmap

  • 投票率向上に向けた啓発手法の検討

    和田淳一郎, 坂口利裕

    横浜市立大学論叢   57   2006.3

    　More details

    Language：Japanese   Publishing type：Research paper (bulletin of university, research institution)  

    researchmap

  • 法政策学における経済学活用の可能性について Invited

    和田 淳一郎

    公共政策研究   4   38 - 43   2004.11

    　More details

    Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：日本公共政策学会  

    CiNii Books

    researchmap

  • 二大政党制をめぐって Invited

    和田淳一郎

    公共選択の研究   2004 ( 42 )   1 - 4   2004.7

    　More details

    Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：勁草書房  

    CiNii Books

    researchmap

  • 選挙区割り問題 Invited

    坂口 利裕, 和田 淳一郎

    オペレーションズ・リサーチ   48 ( 1 )   30 - 35   2003.1

    　More details

    Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：公益社団法人日本オペレーションズ・リサーチ学会  

    CiNii Books

    researchmap

  • The Rise and Decline of Nations after 20 years

    Junichiro WADA

    The bulletin of Yokohama City University. Social science   54 ( 1 )   21 - 32   2003.1

    　More details

    Language：English   Publishing type：Research paper (bulletin of university, research institution)   Publisher：横浜市立大学学術研究会  

    CiNii Books

    researchmap

  • 選挙制度と経済政策 Reviewed

    和田淳一郎

    公共政策（年報）   3   2000.11

    　More details

    Language：Japanese   Publishing type：Research paper (scientific journal)  

    researchmap

  • Senkyo kuwari no saitekika ni tsuite Invited

    93 ( 1 )   109 - 137   2000.4

    　More details

    Language：Japanese   Publishing type：Research paper (bulletin of university, research institution)  

    researchmap

  • 一票の平等について － 経済学的視点から Reviewed

    和田淳一郎

    公共選択の研究   1995 ( 26 )   58 - 67   1996.1

    　More details

    Language：Japanese   Publishing type：Research paper (scientific journal)  

    DOI： 10.11228/pcs1981.1995.26_58

    researchmap

    Other Link： https://www.jstage.jst.go.jp/article/pcs1981/1995/26/1995_26_58/_pdf/-char/ja

  • A Game Theoretical Study of "Heiritsu-sei" Reviewed

    WADA Junichiro

    jjes, Japanese Journal of Electoral Studies   10   32 - 40,124   1995.3

    　More details

    Publishing type：Research paper (scientific journal)   Publisher：Japanese Association of Electoral Studies  

    In the context of "Shou-senkyoku=Hirei-daihyou=Heiritsu-sei, "Duverger's Law" will be studied using a game theoretical model. The main result is two theorems. The Negative Theorem is that exit from an election, which means implicit alliance, occurs only if the Condorcet winner is not the biggest party. The Positive Theorem is that except for the case of a chicken game without suitable focal point, the Condorcet winner always wins the election in the equilibrium.

    DOI： 10.14854/jaes1986.10.32

    researchmap

  • The Japanese Election System: Three Analytical Perspectives

    Junichiro Wada

    University of Maryland   1 - 192   1995.1

    　More details

    Language：English   Publishing type：Doctoral thesis  

    CiNii Books

    researchmap

  • The Liberal Democratic Party as a Coalitional Government

    Junichiro Wada

    The bulletin of Yokohama City University. Social science   45 ( 2 )   p83 - 112   1994.3

    　More details

    Language：English   Publishing type：Research paper (other academic)   Publisher：横浜市立大学学術研究会  

    CiNii Books

    researchmap

  • A Game Theoretical Study of "Duverger′s Law"

    Junichiro WADA

    The bulletin of Yokohama City University. Social science   43 ( 1 )   p237 - 253   1992.3

    　More details

    Language：English   Publishing type：Research paper (bulletin of university, research institution)   Publisher：横浜市立大学学術研究会  

    CiNii Books

    researchmap

  • 議席配分の方法としてのサン=ラグ方式 Reviewed

    和田 淳一郎

    公共選択の研究   1991 ( 18 )   92 - 102   1991

    　More details

    Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：JAPAN PUBLIC CHOICE SOCIETY  

    researchmap

  • Economic Influence of the Apportionment of Representatives Reviewed

    100 ( 1 )   172 - 184   1988.7

    　More details

    Language：Japanese   Publishing type：Research paper (bulletin of university, research institution)  

    DOI： 10.15057/12660

    CiNii Books

    researchmap

  • 政治決定過程の政治経済学的分析

    和田淳一郎

    一橋大学   1987.1

    　More details

    Language：Japanese   Publishing type：Master’s thesis  

    researchmap

  • 政治過程の経済学的分析

    和田淳一郎

    ヘルメス   36   1985.3

    　More details

    Language：Japanese  

    researchmap

▼display all

Books

  • 一票の平等の政治経済学

    和田淳一郎（ Role： Sole author）

    2024.12  （ ISBN:9784326505081 ）

    　More details

  • Redistricting in Comparative Perspective

    Toshihiro SAKAGUCHI, Junichiro WADA, Bernard Grofman, Lisa Handley（ Role： ContributorAutomating the Districting Process）

    Oxford University Press  2008.8  （ ISBN:0199227403 ）

    　More details

    Total pages：348   Language：English  

    ASIN

    researchmap

  • The Political Economy of Japan's Low Fertility

    Junichiro WADA, Frances Rosenbluth（ Role： ContributorThe Political Economy of Daycare Centers in Japan）

    Stanford University Press  2006.12  （ ISBN:0804754861 ）

    　More details

    Total pages：240   Language：English  

    ASIN

    researchmap

  • Handbook of Electoral System Choice

    Junichiro WADA, Josep Colomer（ Role： ContributorJapan: Manipulating Multi-Member Districts - from SNTV to a Mixed System）

    Palgrave Macmillan  2004.12  （ ISBN:1403904545 ）

    　More details

    Total pages：592  

    ASIN

    researchmap

  • Collective Decision-Making:: Social Choice and Political Economy (Recent Economic Thought)

    Junichiro WADA, Norman Schofield, norman schofield（ Role： ContributorBargaining in the Liberal Democratic Party in Japan）

    Springer  1996.9  （ ISBN:9048158001 ）

    　More details

    Total pages：422  

    ASIN

    researchmap

  • The Japanese Election System: Three Analytical Perspectives (Routledge Studies in the Growth Economies of Asia)

    Junichiro Wada（ Role： Sole author）

    Routledge  1996.7  （ ISBN:0415140099 ）

    　More details

    Total pages：128  

    ASIN

    researchmap

  • 公共政策学事典

    日本公共政策学会（ Role： Contributor財政学と公共経済学）

    丸善出版  2024.10  （ ISBN:9784621310243 ）

    　More details

    Total pages：xxiii, 576p   Language：Japanese  

    CiNii Books

    researchmap

  • 公共選択論 = Public choice theory

    （ Role： Contributor選挙制度）

    勁草書房  2022.1  （ ISBN:9784326504909 ）

    　More details

    Total pages：xv, 398p   Language：Japanese  

    CiNii Books

    researchmap

  • 応用数理ハンドブック

    和田淳一郎（ Role： Contributor不平等指数）

    朝倉書店  2013.11 

    　More details

    Language：Japanese   Book type：Dictionary, encyclopedia

    researchmap

  • テキストブック公共選択

    川野辺, 裕幸, 中村, まづる, 小西, 砂千夫, 長峰, 純一, 西川, 雅史, 鷲見, 英司, 堀, 真奈美, 増山, 幹高, 和田, 淳一郎 (経済学), 飯島, 大邦, 宮下, 量久, 荒幡, 克己, 伊藤, 穣, 奥井, 克美, 平井, 友行（選挙制度と投票行動）

    勁草書房  2013.10  （ ISBN:9784326503858 ）

    　More details

    Total pages：xviii, 385p   Language：Japanese  

    CiNii Books

    researchmap

  • ゲーム理論で解く

    和田淳一郎（ Role： Contributor「投票と選挙」をゲーム理論で解く）

    有斐閣  2000.11 

    　More details

  • 現代ミクロ経済学

    和田淳一郎（ Role： Contributor公共選択の経済学、地方分権の経済学）

    東洋経済  2000.6 

    　More details

  • 公共経済学

    和田淳一郎（ Role： Contributor利益集団）

    八千代出版  1998.4 

    　More details

▼display all

MISC

  • 統一地方選挙における横浜市の投票率について Invited

    和田淳一郎

    白バラよこはま   ( 53 )   2023.11

    　More details

  • 教養ゼミ実践報告―Data Visualizationを中核において―

    和田淳一郎

    横浜市立大学論叢   71 ( 2 )   269 - 298   2020.2

    　More details

  • 一票の平等を目指して経済学から言えること

    和田淳一郎

    公共選択の研究   ( 57 )   2012.2

    　More details

  • 横浜市二十代の投票行動 Invited

    和田 淳一郎

    白バラよこはま（横浜市選挙管理委員会）   /36,2-4   2006

    　More details

    Language：Japanese  

    researchmap

  • 選挙管理委員会との共同研究から Invited

    和田 淳一郎

    白バラよこはま（横浜市選挙管理委員会）   /35, 2-4   2005

    　More details

    Language：Japanese  

    researchmap

  • 中央政府は租税競争においていかにあるべきか ～シミュレーションによる一考察

    和田 淳一郎

    国と地方の役割分担～税制と社会保障を中心として (研究代表者石弘光：研究課題番号09430017)   1999.3

    　More details

    Publishing type：Meeting report  

    researchmap

  • 選択行動の統計分析:非序列化離散変数を従属変数とする統計モデルの比較 Invited

    堀内 勇作, 和田 淳一郎

    公共選択の研究   1999 ( 33 )   60 - 63   1999

    　More details

    Language：Japanese   Publisher：JAPAN PUBLIC CHOICE SOCIETY  

    researchmap

  • 「並立制の研究: 構造・学習論からの分析」に寄せて Invited

    和田 淳一郎

    公共選択の研究   1994 ( 24 )   109 - 110   1994.12

    　More details

    Language：Japanese   Publishing type：Rapid communication, short report, research note, etc. (scientific journal)   Publisher：JAPAN PUBLIC CHOICE SOCIETY  

    DOI： 10.11228/pcs1981.1994.24_109

    researchmap

  • 自民党政権形成のゲーム理論的分析

    和田淳一郎

    ( 21 )   1993.5

    　More details

▼display all

Research Projects

  • Party VoteとPersonal Vote～選挙制度に関わる視座から

    Grant number：22K01331  2022.4 - 2025.3

    日本学術振興会  科学研究費助成事業 基盤研究(C)  基盤研究(C)

    和田 淳一郎

    　 More details

    Grant amount：\4160000 （ Direct Cost: \3200000 、 Indirect Cost：\960000 ）

    researchmap

  • A Study of Local Assembly Elections

    Grant number：17K03550  2017.4 - 2020.3

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (C)  Grant-in-Aid for Scientific Research (C)

    Wada Junichiro

    　 More details

    Grant amount：\4420000 （ Direct Cost: \3400000 、 Indirect Cost：\1020000 ）

    We argue that a difference in district magnitude - the number of seats per district - causes variations in the way voters are affected by smiles in their voting behaviors. Using data from local assembly elections in an urban area in Japan, where both SMDP and MMDs/SNTV are used, we showed how a candidate’s smile is effective in attracting votes in SMDP, but it does not increase the vote share in the MMDs/SNTV system.
    We show how to decompose the divergence from party votes share to party seats share into the inequality of vote value, so-called wasted votes, and geographical lessoning with α-divergence. We decompose the results for the US congressional elections and Japanese congressional elections with this identity, but without any help of causal inference. Using the optimization model, we identified optimal combined districts and evaluated the effects of the combined districts.

    researchmap

  • A Comprehensive Analysis of Malapportionment around the World: Situation, Causes, and Consequences

    Grant number：26285032  2014.4 - 2017.3

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B)  Grant-in-Aid for Scientific Research (B)

    Kasuya Yuko, HORIUCHI Yusaku, HIROI Taeko

    　 More details

    Grant amount：\15730000 （ Direct Cost: \12100000 、 Indirect Cost：\3630000 ）

    This project analyses the situation, causes, and consequences of legislative malapportionment around the world. It has three research components: (1) measuring the degree of malapportionment, (2) investigating the causes of malapportionment, and (3) analyzing the its consequences. The first part yielded the database that compiles the degree of lower chamber malapportionment for 140 countries. Several papers were written on the causes of malapportionemnt. The main findings are that the degree of malapportionment increases as the electoral competition becomes more competitive, and decreases as the degree of executive constraints (such as the presence of independent judiciary). As for the consequences, members of this project found that malapportionment harms economic development of overrepresented districts in the case of Brazil. In the context of electoral authoritarianism, it reduces the electoral violence.

    researchmap

  • Integrative Study of One-man 0ne-vote

    Grant number：25380161  2013.4 - 2016.3

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (C)  Grant-in-Aid for Scientific Research (C)

    Wada Junichiro

    　 More details

    Grant amount：\5070000 （ Direct Cost: \3900000 、 Indirect Cost：\1170000 ）

    To bring apportionment closer to quotas, we introduce f-divergence for utilitarianism and Bregman divergence for consistent optimization. Even in our less restricted condition, we find that we must use α-divergence for optimization that induces the same divisor methods correspond to the maximization of the Atkinson social welfare function, which is bounded by constant relative risk aversion.
    Our measurement of disproportionality is α-divergence. By using α-divergence, we can easily understand the philosophy of “dead set election” because changing the parameter of the α-divergence or social welfare function gives the optimal apportionment solution. Furthermore, α-divergence is decomposable based on the apportionment and districting stages. In this study, we investigate the philosophical differences in 73 countries and clarify the factors of malapportionment in Italy and Taiwan using the decomposability of α-divergence.

    researchmap