1.0大阪大学大学院国際公共政策研究科 大阪大学法学部国際公共政策学科 | OSIPP（Osaka School of International Public Policy）https://www.osipp.osaka-u.ac.jp/ja/Libraryhttps://www.osipp.osaka-u.ac.jp/ja/news/author/library/rich600338<blockquote class="wp-embedded-content" data-secret="KiFDYpg0r3"><a href="https://www.osipp.osaka-u.ac.jp/ja/news/achievement202606/">2026年6月の研究業績</a></blockquote><iframe sandbox="allow-scripts" security="restricted" src="https://www.osipp.osaka-u.ac.jp/ja/news/achievement202606/embed/#?secret=KiFDYpg0r3" width="600" height="338" title="“2026年6月の研究業績” — 大阪大学大学院国際公共政策研究科 大阪大学法学部国際公共政策学科 | OSIPP（Osaka School of International Public Policy）" data-secret="KiFDYpg0r3" frameborder="0" marginwidth="0" marginheight="0" scrolling="no" class="wp-embedded-content"></iframe><script> /*! This file is auto-generated */ !function(d,l){"use strict";l.querySelector&&d.addEventListener&&"undefined"!=typeof URL&&(d.wp=d.wp||{},d.wp.receiveEmbedMessage||(d.wp.receiveEmbedMessage=function(e){var t=e.data;if((t||t.secret||t.message||t.value)&&!/[^a-zA-Z0-9]/.test(t.secret)){for(var s,r,n,a=l.querySelectorAll('iframe[data-secret="'+t.secret+'"]'),o=l.querySelectorAll('blockquote[data-secret="'+t.secret+'"]'),c=new RegExp("^https?:$","i"),i=0;i<o.length;i++)o[i].style.display="none";for(i=0;i<a.length;i++)s=a[i],e.source===s.contentWindow&&(s.removeAttribute("style"),"height"===t.message?(1e3<(r=parseInt(t.value,10))?r=1e3:~~r<200&&(r=200),s.height=r):"link"===t.message&&(r=new URL(s.getAttribute("src")),n=new URL(t.value),c.test(n.protocol))&&n.host===r.host&&l.activeElement===s&&(d.top.location.href=t.value))}},d.addEventListener("message",d.wp.receiveEmbedMessage,!1),l.addEventListener("DOMContentLoaded",function(){for(var e,t,s=l.querySelectorAll("iframe.wp-embedded-content"),r=0;r<s.length;r++)(t=(e=s[r]).getAttribute("data-secret"))||(t=Math.random().toString(36).substring(2,12),e.src+="#?secret="+t,e.setAttribute("data-secret",t)),e.contentWindow.postMessage({message:"ready",secret:t},"*")},!1)))}(window,document); //# sourceURL=https://www.osipp.osaka-u.ac.jp/wp-includes/js/wp-embed.min.js </script> https://www.osipp.osaka-u.ac.jp/wp-content/uploads/2026/03/Achievement-2.jpg20001000OSIPP基幹講座教員から報告があった研究業績をご紹介します。 ・久保田雅則 先生　・前川和歌子 先生・川窪悦章 先生　・山下真美子 先生Masanori Kubota（論文）Yukawa, Taku, Kaoru Hidaka, Masanori Kubota, and Kaori Kushima. 2026. “Returning Home to Politics: The Political Determinants of Ousted Leaders’ Trajectories after Exile.” International Political Science Review, April. （査読あり）https://doi.org/10.1177/01925121261423070Abstract: Exile has traditionally been treated as a permanent removal from domestic politics. Yet many deposed leaders seek exile abroad and later re-enter politics after returning home. This study asks under what conditions exiled leaders can regain political power, focusing on their ability to return home as a crucial step in this process. It argues that the nature of power loss – coup or popular uprising – shapes the prospects for return to the home country. By anchoring the analysis in the concrete process of returning home, the study refines our understanding of how different modes of ouster influence post-tenure trajectories. Using data from 101 leaders exiled between 1970 and 2020, the study tests its theoretical expectations through quantitative analyses and case studies. The findings reveal that leaders ousted in coups are far more likely to return, highlighting the political logic linking the mode of power loss, repatriation and post-exile political re-engagement.Wakako Maekawa（論文）Wakako Maekawa; Jean Francois Koly Onivogui; Wayne Tan“United Nations peacekeeping operations and health expenditure in Africa”Defence and Peace Economics, Online first, June 7, 2026.（査読あり）https://doi.org/10.1080/10242694.2026.2681565Abstract: While UNPKOs’ effectiveness on health outputs in host countries has been extensively investigated, their impact on health inputs–health expenditures – has been overlooked. We explore the effectiveness of UNPKOs on health inputs and argue that UNPKOs influence the host state’s decision on resource allocation through healthcare promotion-related mandates, which address cross-sectoral trade-offs, induce external funding, and enhance efficiency. Using African countries that experienced civil wars from 2001 to 2013, the empirical analysis shows that UNPKOs increase expenditures through the humanitarian relief and public health mandate, supporting the external channel mechanism. Our additional analysis shows that bureaucratic capacity enhancement through state authority mandates is a promising mechanism, although it is insufficient to influence health expenditures.川窪悦章（著書）川窪悦章「第4章 視点05：企業はどのように影響を及ぼし合うのか？」日経トップリーダー編『日本を救う最強の中堅企業：次の成長ステージを目指すための教科書』（日経BP、2026年）242-247頁。（なお、第4章は6名の専門家による分担執筆となります。）https://bookplus.nikkei.com/atcl/catalog/26/04/16/02586/概要：本書は、日本の経済成長を担う中堅企業に注目し、企業成長を高める方法を学術および実務の観点から解説する書籍である。担当した第4章では、特に企業のマネジメントと取引関係に焦点を当てて、既存研究から示唆される企業成長戦略について議論している。Mamiko Yamashita（DP）Mamiko Yamashita“Pricing Kernel Monotonicity and the Conservativeness of Risk-Neutral Forecasts”OSIPP Discussion Paper: DP-2026-E-008, May 29, 2026https://www.osipp.osaka-u.ac.jp/archives/DP/2026/DP2026E008.pdfAbstract: This paper studies the relationship between option-implied, risk-neutral forecasts and their real-world counterparts through the lens of stochastic dominance and pricing kernel monotonicity. We show that when the pricing kernel is weakly decreasing in asset payoffs, the real-world distribution first-order stochastically dominates the risk-neutral one, implying that the risk-neutral forecast is more conservative. The ordering is reversed when the pricing kernel is weakly increasing, implying that risk-neutral forecasts may be more optimistic rather than conservative. We further show that this monotonicity is closely linked to the dependence between asset payoffs and aggregate consumption. Our results provide a new perspective on the pricing kernel puzzle, an empirical finding that pricing kernels for major market indices are often non-monotonic. Our results, together with the pricing kernel puzzle, suggest that the commonly held belief in the conservativeness of risk-neutral forecasts is not generally warranted, even for broad market indices.