KEIO RESEARCHERS INFORMATION SYSTEM

Career 【 Display / hide 】

Career 【 Display / hide 】

• 2015.07

  -

  2017.05

  Asian Development Bank Institute, Research Department, Research Associate

• 2017.06

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  2019.03

  Hitotsubashi University, Hitotsubashi Institute for Advanced Study, Specially Appointed Research Associate

• 2019.04

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  2022.03

  Hitotsubashi University, Hitotsubashi Institute for Advanced Study, Specially Appointed Assistant Professor

• 2022.04

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  2025.03

  Asian Growth Research Institute, Research Division, Assistant Professor

• 2022.04

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  Present

  Hitotsubashi Institute for Advanced Study, HIAS Health, Visiting Researcher

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Papers 【 Display / hide 】

Papers 【 Display / hide 】

• Valuing health across groups: a cross-sectional population-based willingness-to-pay survey in Bhutan

  Ying Yao, Md. Mizanur Rahman, Pempa, Yot Teerawattananon, Ryota Nakamura

  BMJ Global Health 10 ( 8 )  2025.08

  Research paper (scientific journal), Accepted

  　View Summary

  Introduction Context-specific cost-effectiveness thresholds (CETs) informed by societal willingness to pay (WTP) are crucial for healthcare resource allocation in low- and middle-income countries. This study investigated WTP for health per quality-adjusted life year (QALY) in Bhutan. Methods A WTP survey was conducted alongside the 2023 National Health Survey in Bhutan, sampling 1869 households. Using contingent valuation, respondents assigned monetary values to three hypothetical scenarios: 1 year of cancer symptom-free life, 1 year of perfect health and 5 years of perfect health. We used generalised linear regression to estimate WTP, controlling for demographic, socioeconomic and health-related factors, as well as elicitation methods. Multilevel analyses examined WTP variations within and between districts. Results WTP estimates were 76 836 Bhutanese ngultrum (BTN) (0.26 times gross domestic product (GDP) per capita; 95% CI: 71 397 to 82 275) for a year without cancer symptoms, 104 381 BTN (0.35 times GDP per capita; 95% CI: 96 405 to 112 357) for 1 QALY and 235 237 BTN (0.78 times GDP per capita; 95% CI: 218 674 to 251 800) for 5 QALYs. WTP variations were driven by within-district individual characteristics, particularly income and education, rather than between-district differences. Conclusion Minimal between-district WTP variations support a national-level CET for Bhutan. However, WTP-based CETs would be biased upward by wealthier and more educated groups. This bias could justify expensive technologies that strain public resources in Bhutan's government-funded healthcare system.

  • Access to Document (DOI)

• Does Environmental Regulation Matter for Income Inequality? New Evidence from Chinese Communities

  Huang B., Yao Y.

  Journal of the Association of Environmental and Resource Economists (University of Chicago Press)  10 ( 5 ) 1309 - 1334 2023.09

  Research paper (scientific journal), Joint Work, Accepted,  ISSN  23335955

  　View Summary

  This study uses data from an ongoing, open-cohort, longitudinal China Health and Nutrition Survey to examine how the environmental regulation aimed at abating sulfur dioxide (SO<inf>2</inf>) alters income distribution. We find that this regulation induces a 14%–27% decrease in income inequality, depending on the measurement method. An improvement in income inequality is achieved by lowering the wages of high-income groups while keeping the wages of low-income groups (especially blue-collar workers) unchanged. This change in the labor market can be attributed to a policy that primarily targets emissions from power plants while leaving the manufacturing sector unaffected. As a result, the manufacturing sector continues to create jobs and absorb the blue-collar workers dismissed from other sectors, mitigating the widening income gap. Our study sheds new light on the role of environmental policy in reshap-ing the labor market and its implications for income distribution.

  • Access to Document (DOI)

• Price-Quality Trade-off in Procurement Auctions With an Uncertain Quality Threshold

  Ying Yao, Makoto Tanaka

  Journal of Economic Behavior & Organization 177   56 - 70 2020.09

  Research paper (scientific journal), Joint Work, Accepted,  ISSN  0167-2681

  • Access to Document (DOI)

• The Educational Gap in Tar and Nicotine Content in Purchases of Cigarettes: An Observational Study Using Large-Scale Representative Survey Data From Japan

  YingYao, Ryota Nakamura, Nazmi Sari

  Preventive Medicine 129   105828 2019.12

  Research paper (scientific journal), Joint Work, Accepted,  ISSN  0091-7435

  • Access to Document (DOI)

• Income Distribution and Health: Can Polarization Explain Health Outcomes Better than Inequality?

  Ying Yao, Guanghua Wan, Dongfang Meng

  European Journal of Health Economics 20   543 - 557 2018.12

  Research paper (scientific journal), Joint Work, Accepted

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Research Projects of Competitive Funds, etc. 【 Display / hide 】

Research Projects of Competitive Funds, etc. 【 Display / hide 】

• Drug Innovation for Equitable Healthcare

  2025.04

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  2028.03

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

• Improving the Efficiency of Healthcare Resource Allocation in Asia

  2021.04

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  2025.03

  Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Grant-in-Aid for Scientific Research (A), Coinvestigator(s)

• Workshop on the Sustainability of Health, Environment, and Development

  2020.06

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  2021.03

  Japan Society for the Promotion of Science, Bilateral Programs, JSPS Bilateral Joint Research Seminar (Interuniversity Cooperation), Principal investigator

• Economic Analyses of Tobacco Purchasing Behavior Using Large-Scale Consumer Panel Data

  2019.04

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  2022.03

  Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, YAO Ying, Grant-in-Aid for Early-Career Scientists, Principal investigator

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  Using large-scale nationally representative consumer panel data in Japan, this study examined the effects of a tax increase and restricting product availability on consumers' product choice and consumption of cigarettes. Regarding the effect of the tax increase, a short-term decrease in cigarette purchases was observed, but this reduction was associated with stockpiling prior to the tax increase. In addition, unlike previous studies, consumers did not switch to higher tar/nicotine products after the tax increase to compensate for losing nicotine levels because of reduced consumption. The adverse health effects remained the same. Regarding the effects of restricting product availability, we found that smokers not only purchased fewer cigarettes but also chose products with less tar and nicotine content. In contrast to tax increases, the effects of interventions that limit product availability can persist over time.

• Research on Cost-Effectiveness Thresholds in Healthcare

  2018.04

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  2021.03

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

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  二年目は課題研究を遂行しつつ、研究内容や途中経過について主に国外の研究会で発表を行った。また、研究成果として論文や書籍を出版した。主な成果は以下の通り。
  <BR>
  （１）医療技術評価の実施と政策意思決定に関して国際共同論文を専門誌等で発表した。さらに後続研究を進めている。（２）医療における費用対効果の閾値の議論を含んだ医療経済学に係る書籍を共同執筆して日本評論社から出版した。特に書籍の三章や五章では、医療における費用対効果評価を中心に扱い、費用対効果の閾値について日本や世界での論点を整理した。（３）ブータン王国における費用対効果の閾値について研究協力の覚書をブータン保健省と調印した。また、年度中２度にわたりブータン保健省を訪問して研究発表、政策会議、データ整備を行った。さらに、セネガル国家医療保障庁との会議を行い、本研究課題のテーマを含めて医療技術評価導入に関して研究協力するための準備を行うことで合意し、国連開発計画や国際協力機構の支援で同庁職員三名をフィリピンでの費用対効果評価のシンポジウム、およびPrince Mahidol Award Conferenceに招致して議論を行った。（４）日本における費用対効果の閾値の推定の作業を進めた。具体的には医療費や死亡率等に関するデータを収集・整理して回帰分析による医療費の限界効果について推定を行った。
  <BR>
  その他、関連学会・シンポジウムにおいて研究成果や途中経過、展望について発表を行うと共に関連研究者との面談・議論を行い研究実施上の知見を得た。なお、当初の研究計画ではインドネシアにおける費用対効果の閾値の推定を行う予定であったが、当初予見できなかった研究予算上及び研究実施上の困難があり断念した。

Courses Taught 【 Display / hide 】

Courses Taught 【 Display / hide 】

• TOPICS IN APPLIED ECONOMICS AND POLICY

  2025

• SEMINAR: SOCIAL POLICY

  2025

• SEMINAR: APPLIED ECONOMICS AND POLICY

  2025

• SEMINAR: APPLIED ECONOMICS

  2025

• RESEARCH SEMINAR B

  2025

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