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Working Papers


Immigration and Innovation. Lessons from the Quota Acts (with Sahar Parsa and Shmuel San).  R&R at Econometrica. Slides. 45m Presentation. Coverage in the New York Times and here, Washington Post, WSJ, Behavioral Scientist, Marginal Revolution, Forbes, Forbes again, and the Ezra Klein Show. Code to scrape patents.
  • The United States first adopted immigration quotas for “undesirable” nationalities in 1921 and 1924 to stem the inflow of low-skilled Eastern and Southern Europeans (ESE). This paper investigates whether these quotas inadvertently hurt American science and invention. Detailed biographic data on the birth place, as well as immigration, education, and employment histories of more than 80,000 American scientists reveal a dramatic decline in the arrival of ESE-born scientists after 1924. An estimated 1,170 ESE-born scientists were missing from US science by the 1950s. To examine the effects of this change on invention, we compare changes in patenting by US scientists in the pre-quota fields of ESE-born scientists with changes in other fields in which US scientists were active inventors. Methodologically, we apply k-means clustering to scientist-level data on research topics to assign each scientists to a research field, and then compare changes in patenting for the pre-quota fields of ESE-born US scientists with the pre-quota fields of other US scientists. Baseline estimates indicate that the quotas led to 68 percent decline in US invention in ESE fields.  Decomposing this effect, we find that the quotas reduced not only the number of US scientists working in ESE fields, but also the number of patents per scientist. Firms that had employed ESE-born immigrants before the quotas experienced a 53 percent decline in invention. The quotas damaging effects on US invention persisted into the 1960s.

The Ms. Allocation of Talent  (with Moritz Lubczyk)
  • Despite improvements in the allocation of talent, women continue to be underrepresented in innovation. This paper investigates whether changes in the allocation of talent could close this innovation gender gap. Linking 70,000 scientists with their patents, we find that the underrepresentation of women today is a continuation of a long-run trend that was already in place for scientists born in the 1920s. OLS estimates indicate that the low share of female scientists in patent-intensive STEM fields is the main driver of this persistent gender gap in innovation. We interpret these findings through the lens of a Roy (1951) model of field choice with gender distortions. To test the model’s predictions and to identify the causal effects of gender differences in the allocation of talent, we exploit an exogenous shock in female representation due to WWII. As men enlisted in the war, the scarcity of male scientists pulled female scientists into patent-intensive research fields in STEM. Using variation in enlistment as an instrument for female entry, we find that one additional woman becomes an inventor for every five women entering STEM. Using data on PhDs and elite education, we show that female scientists are positively selected and that selection decreases during WWII when more women enter science. Counterfactual estimates imply that, if women were as likely to work in STEM fields as men, the innovation gender gap would close in 38, rather than 118 years. ​

Rosie the Researcher: How Female WWII Entrants Changed Science in US Firms with (Moritz Lubczyk)
  • What are the productivity effects of hiring underrepresented talent? We investigate this question in the context of World War II, when a shortage of male labor forced US firms to hire female scientists. Using new data on the scientific personnel of US firms, we exploit firm-level variation in exposure to enlistment as an instrument for female hires. Firms exposed to enlistment hired 1.4 times more female scientists during the war. Firms that hired at least 1 female scientist during the war produced 1 additional publication per 11 scientists on average after the war - but no additional patents. Data on the job titles of scientists document significant heterogeneity in the tasks that female scientists performed across firms. Firms that placed women in leadership roles experienced an increase in patenting, while firms that used women as librarians had an increase in publications, but not innovation.  
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Inequality in Science: Who Becomes a Star? (with Anna Airoldi). Code for census matching.
  • Does socioeconomic status (SES) influence who becomes a “star”? To investigate this question, we exploit a unique feature of the American Men of Science (1921), for which scientists ranked each other to identify the “leading men” in their discipline. Using machine-learning tools to link scientists with their childhood home, we show that the underrepresentation of low-SES individuals in science today continues a pattern from the early 20th century: Boys from the top half of the distribution of SES are much more likely to become scientists than those from the bottom half. Investigating peer recognition, we find that children from high-SES families have nearly 40% higher odds of becoming “stars” – even controlling for disciplines and publications. This link between SES and stardom is robust to birth order, family structure, parents’ immigration status, and even neighborhood-level differences in education. Instead, SES appears to affect stardom through parental wealth, neighborhood-level differences in income, elite undergraduate education, and social connections. 

Shell Shock: How Exposure to Combat Affected American Scientists After WWII (with Aaron Chen).
  • How does exposure to combat affect productivity? We investigate this question for scientists who fought in WWII. To measure exposure to combat, we apply natural language processing to match 84,556 scientists with 9 million archival records of enlistment and hospitalizations. Event studies compare changes in publishing after service for enlisted with non-enlisted draft-eligible scientists of similar age, education, occupation, and marital status. We find that enlisted scientists are less likely to publish for 10 years after the end of their military service. This decline is not driven by time away from research: scientists who had served in combat suffer a large and persistent additional decline in productivity relative to other enlisted scientists. Instead, it appears to be driven by a persistent decline in co-authoring: Solo-authored publications recover to pre-enlistment levels after exposure to combat, while co-authoring stays low. Scientists who have experienced combat also stop publishing at an earlier age. Using hospital admission to identify scientists with combat wounds, we show that declining productivity after combat cannot be explained by physical wounds.

Operation Paperclip: Nazi Scientists and US Innovation (with Bang Dinh Ngyuen)
  • Operation Paperclip brought 783 German scientists, many of them NSDAP members, to the United States after 1947. Its goal was to advance US innovation in strategically important fields, including rocketry and nuclear physics. To examine how Operation Paperclip influenced US innovation, we compare changes in patenting after 1947 in the pre-war fields of Paperclip scientists with changes in the pre-war fields of other German scientists who were targeted by the program but did not come to the United States. OLS estimates indicate that, after 1947, that innovation increased by more than 60 percent in Paperclip fields relative to the fields of other targeted German scientists. These estimates are robust to controlling for variation in government-funding. Placebo estimates for Britain show no significant increase. Using the pre-war fields of scientists who were forcibly relocated to the USSR as an instrument for Paperclip fields confirms the large increase in innovation. Linking scientists with archival lists of NSDAP memberships, we find that fields with Nazi scientists experienced a disproportionate increase in innovation. Firm-level analyses show that firms that hired Paperclip scientists produced 31 percent more patents after 1947 compared with similar firms. 

McCarthy and the Red-ucators: Effects of Political Persecution on Science (with Sahar Parsa). Slides. 
  • This paper examines the effects of political persecution during McCarthyism on American science. Between 1949 and 1953 the National Council of American Education (NCAE) published lists of "Red-ucators" - professors and other scientists who were publicly accused of associations with subversive, communist organizations. Event studies of publications and citations show that targeted scholars experienced a large and persistent decline in their research output. After the accusations, targeted scholars were 10% less likely to publish, and they published 25% fewer papers compared with other scholars in the same fields and at similar institutions. Scientists who were accused of multiple subversive affiliations suffered most. Notably, citations to existing work by targeted scholars declined only temporarily during the height of the movement and recovered as McCarthyism lost its force.

(De-)Funding the Arts (with Michela Giorcelli). Slides.
  • How does public funding affect creative output in the arts? To answer this question, we exploit exogenous variation in exposure to public funding cuts due to Italy’s unification in 1861. Using theater-level performance data as a measure of creativity, we find that theaters more exposed to cuts put on fewer shows, produced fewer new works, and shifted towards more popular forms of entertainment. The impact of cuts was more severe in areas with low income and smaller cities. In the long run, theaters more exposed to funding cuts were more likely to close or be replaced by movie theaters.

Financing Creativity: Crowdfunding in 19th-Century Fiction (with Chelsea Carter and Megan MacGarvie).
  • Demand uncertainties create major obstacles for financing technological innovation, as well as creativity in the arts. This paper uses detailed book-level data on Romantic Period English literature to investigate crowdfunding as a mechanism to finance innovation in the presence of demand uncertainties. A simple model yields conditions under which authors choose alternative financing, and specifically crowdfunding. We show that new authors, female authors, and authors in new genres face substantially greater demand uncertainty than established authors, men, and authors working in established genres.. Detailed book-level contract data reveal that entrants, women, and authors in new genres are more likely to crowdfund. We find that crowd-funded works have lower payoffs on average but are substantially more likely to become a major hit. Exploring variation across genres, we show that crowdfunded novels for women (and by women) were more likely to be published in multiple editions, suggesting that realized demand exceeded expected demand in this emerging genre. Crowdfunded women’s novels are also more likely to be translated and have an increased probability of long-run success. Using text analysis to measure novelty, we show that crowd-funded titles are likely to present new ideas than publisher-funded works. ​

Occupations of the Black Elite (with Laura Carreno Carrillo)
  • This paper uses newly digitized data from a Who is Who of the Black elite between 1915 and 1950 to investigate the misallocation of Black talent before Civil Rights. First, we document differences in the occupations of prominent Black and white Americans. While members of the white elite were most likely to be lawyers and judges (13%), authors (12%), or college faculty and deans (8%), members of the Black elite were most likely to hold similar occupations with lower socioeconomic status as teachers (16%), physicians (13%) or clergy (11%). To better understand the historical misallocation of talent, we digitize information on the skill-content of occupations from the Dictionary of Occupational Titles (DOT 1956). Using data on skills, we match occupations of the Black elite with occupations of the white elite requiring similar skills. Comparing counterfactual with observed occupations for members of the Black we investigate patterns of underrepresentation and how these patterns changed over time..


​Books


Pirates and Patents. An Economic History of Intellectual Property and Innovation in Europe and the United States. Under contract with Princeton University Press.
  • Patents are intended to encourage innovation and economic growth. Yet, throughout history, countries have chosen piracy instead of patenting during their most critical phase of economic development. This book documents how the United States and European countries have used piracy in their early stages economic development to catch up to the technology frontier, and how they switched to patents once they reached the frontier. 

Economics of Research and Innovation in Agriculture. Editor. Introduction. University of Chicago Press, 2021.
  • Feeding the world’s growing population is one of the most critical policy challenges for the 21st century. With tightening constraints on natural resources, such as water and arable land, agricultural innovation is quickly becoming the most promising path meet the nutrient needs for future generations. Moreover, the increasing variability in the world’s climate intensifies the need for developing new crops that can tolerate extreme weather. Despite the urgency of this task, there is an active discussion on the returns to public and private spending in agricultural R&D. Since the 1990s, many of the world’s wealthier countries have scaled back their share of GDP devoted to agricultural R&D. Dwindling public support leaves universities, which, historically, have been a major source of agricultural innovation increasingly dependent on funding from industry, with uncertain effects on agricultural research. To help address these issues, this book provides new economic evidence on the sources of agricultural innovation, on challenges of measuring productivity, on the role of universities and their interactions with industry, and on emerging mechanisms to fund agricultural R&D.


Publications, Data, & Code


Women in Science

Women in Science. Lessons from the Baby Boom (with Scott Kim). Slides. Data and Replication files. Econometrica: Sep, 2025, Volume 93, Issue 5. pp. 1521-1560. Coverage in the Chronicle of Higher Education, Times Higher Education and Expresso.


Immigration and Science

German Jewish Émigrés and US Invention (with Alessandra Voena and Fabian Waldinger). American Economic Review, 2014, Volume 104(10), pp. 3222-55. Slides. Replication files and data. NPR interview on immigration and innovation. Coverage in NPR Cosmos and Culture, and Washington Post 2020, 2022, and 2023 .


​Copyrights and Creativity

Copyright and Creativity. Evidence from Italian Operas (with Michela Giorcelli). Appendix. Journal of Political Economy, Volume 128, Number 11, November 2020, pp. 4163-4210. Summary at Vox, on Weixin (also as full paper), and in the NBER Digest. Video by EconFilms. Interview on Freakonomics (min 17:40-28.00). Interviews in the IMF podcast and on NPR.  And in stick figures.

Effects of Copyright on Science - Evidence from the WWII Book Republication Program (with Barbara Biasi). Forthcoming in the AEJ Microeconomics. Vol. 13, No. 4, November 2021. pp. 218-60. Coverage in the NBER Digest, the Economist, Vox, Cato, and the Austrian Science ORF. Interview with ORF.
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​Dead Poet’s Property – How Does Copyright Influence Price? (with Xing Li and Megan MacGarvie). RAND Journal of Economics 49 (1): 2018, pp. 181-205. Slides.

Copyright and the Profitability of Authorship (with Megan MacGarvie) in Avi Goldfarb, Shane Greenstein, and Catherine Tucker (eds). The Economics of Digitization: An Agenda. 2013. Summary in the Washington Post, Freakonomics.

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Patents and Innovation

Innovation and Patents, Louis Cain, Price Fishback, and Paul Rhode (editors) Oxford Handbook of Economic History, forthcoming.

​Patent Citations - An Analysis of Quality Differences and Citing Practices in Hybrid Corn (with Joerg Ohmstedt and Paul Rhode). Management Science, Volume 64, Issue 4. April 2018, pp. 1477-1973. Data on patents, hybrids, citations, and improvements in yields. Slides.
  
Compulsory Licensing and Innovation - Evidence from German Patents after World War I (with Joerg Baten and Nicola Bianchi).  Journal of Development Economics, Volume 126, May 2017. Slides. Data on German patents for chemical inventions, 1900-30.

Patent Pools, Competition and Innovation.  Evidence from 20 Industries under the New Deal (with Ryan Lampe). Journal of Law, Economics, & Organization, Volume 32, 2016, pp. 1-36.  Oliver Williamson Prize, Runner-Up for Best Paper Published in 2016. Do file and data.

Patents and Innovation in Economic History. Annual Review of Economics, Volume 8, 2016. Working paper.

Patent Pools and Innovation in Substitute Technologies – Evidence from the U.S. Sewing Machine Industry (with Ryan Lampe). RAND Journal of Economics, 2014, Volume 44, Issue 4, pp. 757-778. Do file and data.

Compulsory Licensing: Evidence from the Trading with the Enemy Act (with Alessandra Voena). The American Economic Review. Volume 102, Issue 1, February 2012, pp. 396–427. Slides. Replication files and data.

Prizes, Publicity, and Patents – Non-Monetary Awards as a Mechanism to Encourage Innovation (with Tom Nicholas). Journal of Industrial Economics, 2013 Volume 61: pp. 763–788. Slides. Data on prizes awarded at the Crystal Palace Fair in 1851.

Patents and Innovation – Evidence from Economic History. Journal of Economic Perspectives, Volume 27, Number 1, Winter 2013, pp. 23–44.

Innovation without Patents – Evidence from World’s Fairs The Journal of Law and Economics, Volume 55, No. 1, February 2012, pp. 43-74.  Individual-level data on British exhibits, prizes, and patents.

Did Plant Patents Create the American Rose? (with Paul Rhode) in Joshua Lerner and Scott Stern (eds). The Rate and Direction of Technological Change, Chicago University of Chicago Press, 2012, pp. 413-41.

Patent Pools:  Licensing Strategies in the Absence of Regulation (with Ryan Lampe). Advances in Strategic Management, Volume 29, 2012, pp. 69-86.

Do Patents Weaken the Localization of Innovations?  Evidence from World's Fairs, 1851-1915. The Journal of Economic History, Volume 71, Number 2, June 2011, pp. 363-382.  Individual-level data for 1851 exhibits from Britain and France with locations.

Do Patent Pools Encourage Innovation?  Evidence from the 19th-Century Sewing Machine Industry with Ryan Lampe.  The Journal of Economic History, Volume 70, Issue 04, December 2010, pp. 898-920.  Do-file, main data, and per stitches per minute data.

How Do Patent Laws Influence Innovation?  Evidence from Nineteenth-Century World Fairs, The American Economic Review, Volume 95, Number 4, September 2005, pp. 1214-1236. Slides. Data for regressions; individual-level data with locations for Britain and France. Data on all prizes in 1851.  Summaries in the New York Times, Washington Post, Wirtschaftswoche (German), and El Espanol (Spanish). An AI-generated 11-minuted podcast.

Was Electricity a General Purpose Technology?  Evidence from Historical Patent Citations with Tom Nicholas, The American Economic Review, Papers and Proceedings, May 2004, vol. 94, no.2, pp.388-394.


​Education and Innovation

Biasi, Barbara, David J. Deming, and Petra Moser. “Education and Innovation.” in Aaron Chatterji, Josh Lerner, Scott Stern and Michael J. Andrews (eds.) The Role of Innovation and Entrepreneurship in Economic Growth, University of Chicago Press, 2020. Cited in the Economic Report of the President, 2025. 


Creativity and Mental Health

​Career Effects of Mental Health (with Barbara Biasi and Michael Dahl). Journal of Political Economy Microeconomics, forthcoming. Coverage in Business Insider.

The Role of Bipolar Disorder and Family Wealth in Choosing Creative Occupations (with Barbara Biasi and Michael Dahl). Nature: Scientific Reports 14, 10703. 2024.

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Empirical Methods

Spatial Errors in Count Data Regressions (with Marinho Bertanha). Journal of Econometric Methods, Volume 5, Issue 1, 2016. Code.

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Taste-based Discrimination

Taste-Based Discrimination.  Evidence from a Shift in Ethnic Preferences after WWI. Explorations in Economic History, Volume 49, Issue 2, April 2012, pp. 167–188.


January 2023
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