"Structural Change and the Fertility Transition", [CEPR dp] [Online Appendix] (joint with Benedikt Herz and Markus Brueckner). Review of Economics and Statistics (accepted for publication). Media: [Voxeu] [The Barcelona GSE Voice]
"How the 1906 San Francisco Earthquake Shaped Economic Activity in the American West", [CEPR dp] [NBER wp] (joint with Katherine Eriksson, Casper Worm Hansen, and Lars Lønstrup). Explorations in Economic History (accepted for publication) Media: [Los Angeles Times] [Voxeu]
"Agricultural Risk and the Spread of Religious Communities", [Online Appendix] (joint with Antonio Ciccone). Journal of the European Economic Association, 2018, 16(4), pp.1021-68. Media: [Nada es gratis] [EHES Blog].
"Fertility and early-life mortality: Evidence from smallpox vaccination in Sweden", [Online Appendix] [Poster] (joint with Casper Worm Hansen and Peter Sandholt Jensen). Journal of the European Economic Association, 2018, 16(2), pp. 487-521. Media: [EHES Blog].
"Immigrants' Genes: Genetic Diversity and Economic Development in the US", [Online Appendix] (joint with Markus Brueckner). Economic Inquiry, 2018, vol. 56 (April), pp. 1149-64.
"The Boll Weevil Plague and its Effect on the Southern Agricultural Sector, 1889-1929", (joint with Markus Brueckner and Benedikt Herz). Explorations in Economic History, 2017, vol. 65 (July), pp. 94-105.
"Cultural Diversity and Economic Growth: Evidence from the US During the Age of Mass Migration", [Online Appendix] (joint with Markus Brueckner). European Economic Review, 2013, vol. 64 (November), pp. 76-97.
"Froebel's Gifts: How the Kindergarten Movement Changed the American Family", [CEPR dp] (joint with Francesco Cinnirella). Media: [VoxEU Video] [VoxTalks]
"How the Other Half Died: Immigration and Mortality in US Cities", [CEPR dp] [NBER wp] (joint with James Feigenbaum, Casper Worm Hansen, and Hui Ren Tan). Media: [Frankfurter Allgemeine Sonntagszeitung (in German)]
"The Effect of Immigration on the Economy: Lessons from Closing the Border in the 1920s", [CEPR dp] [NBER wp] (joint with Ran Abramitzky, Leah Boustan, Elior Cohen, and Casper Worm Hansen).[Online Appendix] Media: [Bloomberg] [Economist] [Forbes], Video: [Econimate](permanent working papers: Ager and Hansen (2016, 2017): Media: [The Conversation] [Bloomberg] [Videnskab (in Danish)])
"Killer Incentives: Relative Position, Performance and Risk-Taking among German Fighter Pilots, 1939-45", (joint with Leonardo Bursztyn, Lukas Leucht, and Joachim Voth). Media: [Voxeu] [NBER Digest] [The Times].
"The Intergenerational Effects of a Large Wealth Shock: White Southerners After the Civil War", [CEPR dp] [NBER wp] (joint with Leah Boustan and Katherine Eriksson). Media: [Bloomberg] [Citylab] [Economist] [ProMarket] [Voxeu] [Wall Street Journal] [Washington Post]
"Church Membership and Social Insurance: Evidence from the Great Mississippi Flood of 1927", (joint with Casper Worm Hansen and Lars Lønstrup).
"Bank Entry Regulation and Financial Development: The US Free Banking Experience", (joint with Fabrizio Spargoli).
Work in Progress
"Did the Boll Weevil kick off the Great Migration?", (joint with Richard Baker, Katherine Eriksson, and Benedikt Herz).
"The Making of an American: Public Kindergartens and the Assimilation of Immigrant Children", (joint with Francesco Cinnirella, Katherine Eriksson, and Viktor Malein)
"The accuracy and efficiency of the Consensus Forecast: A further application and extension of the pooled approach", (joint with Marcus Kappler and Steffen Osterloh). International Journal of Forecasting, 2009, vol. 25 (1), pp. 167-181.