Fellow Researchers Profile



Senior Research Fellow

Professor at the University of Tokyo (Economics)
[Research Themes]
Research on economic theory


  • Macroeconomics and Finance



B.A. (Kyoto University)
M.A. (Kyoto University)
Ph.D. (University of Chicago)


Assistant Professor, Brown Uniuversity
Professor, Kyoto University


  • "Debt overhang and lack of lender’s commitment" Journal of Money, Credit, and Banking, forthcoming. (with Keiichiro Kobayashi and Shuhei Takahashi)
  • "Uninsured Idiosyncratic Risk and the Government Asset Laffer Curve" Journal of Macroeconomics, 71, March 2022 (with Shuhei Takahashi).
  • "The Effectiveness of Consumption Taxes and Transfers as Insurance against Idiosyncratic Risk" Journal of Money, Credit, and Banking, 52, 505-530, 2020. (with Shuhei Takahashi)
  • "Why prices don't respond sooner to a prospective sovereign debt crisis," Review of Economic Dynamics, 29, 235-255, 2018. (with R. Anton Braun)
  • "The optimum quantity of debt for Japan," Journal of the Japanese and International Economies, 46, 17-26, 2017. (with Shuhei Takahashi)
  • "Constrained inefficiency and optimal taxation under uninsurable risks." Journal of Publc Economic Theory, 18, 1-28, 2016. (with Piero Gottardi and Atsushi Kajii).
  • "Optimal tacation and debt with uninsurable risks to human capital accumulation." American Economic Review, 105, 3443-3470, 2015. (with Piero Gottardi, and Atsushi Kajii).
  • "Safe asset shortages and asset price bubbles." Journal of Mathematical Economics, 53, 164-174, 2014. (with Kosuke Aoki and Kalin Nikolov)
  • "Global liquidity trap." Journal of Monetary Economics, 60, 936-949, 2013. (with Ippei Fujiwara, Nao Sudo, and Yuki Teranishi)
  • "Uninsured countercyclical risk: an aggregation result and application to optimal monetary policy." Journal of the European Economic Association, 10, 1450-1474, 2012. (with R. Anton Braun)
  • "Collateral constraint and news-driven cycles." Macroeconomic Dynamics, 16, 752-776, 2012. (with Keiichiro Kobayashi and Masaru Inaba)
  • "Optimal monetary policy with imperfect unemployment insurance.'' Journal of Economic Dynamics and Control, 34, 365-387, 2010.
  • "Liquidity trap and optimal monetary policy in open economies," Journal of the Japanese and International Economies, 22, 1-33, 2008.
  • "Asset price fluctuations in Japan: 1980-2000," Japan and the World Economy, 20, 129-153, 2008.
  • "Unemployment and indeterminacy," Journal of Economic Theory, 126, 314-327, 2006.
  • "Monetary policy with sticky prices and segmented markets," Economic Theory, 27, 163-177, 2006.
  • "Money and prices under uncertainty," Review of Economic Studies, 72, 223-246, 2005 (with Herakles Polemarchakis).
  • "A business cycle model with variable capacity utilization and demand disturbances," European Economic Review, 49, 1331-1360, 2005.
  • "Catch-up in turn in a multi-country international trade model with learning-by-doing and invention," Journal of Development Economics, 72, 117-138, 2003.
  • "Sunspot fluctuations in asset prices and business cycles in Japan over 1986-1999," Japanese Economic Review, 54, 253-274, 2003.