How does innovation diffuse across countries? In this paper, we document that out-migration promotes the diffusion of innovation from the country of destination to the country of origin of migrants. Between 1870 and 1940, nearly four million British immigrants settled in the United States. We construct a novel individual-level dataset linking British immigrants in the US to the UK census, and we digitize the universe of UK patents over 1853-1899. Using a new shift-share instrument for bilateral migration and a triple-differences design, we document that migration ties contribute to technology diffusion from the US to the UK. Through high-dimensional text analysis, we find that emigrants promote technology transfer, but they also nurture the production of original innovation. Physical return migration is an important driver of this "return innovation" effect. However, we find that the interactions between emigrants and their origin communities promote technology diffusion, even absent return migration. Additionally, we show that migration ties propel knowledge flows by fostering cross-border market integration.

Between 1920 and 1921, Italian emigration to the United States dropped by 85% after the Emergency Quota Act was passed by Congress, a severely restrictive immigration law. Using newly digitized data from Italian historical censuses in a difference-in-differences setting, we leverage variation in exposure across Italian districts to this large restriction on human mobility. More exposed districts display a sizable population increase. Moreover, the policy substantially hampered the adoption of labor-saving technology. Consistently with directed technology adoption theory, manufacturing employment markedly increased, and evidence suggests that "missing migrants" whose migration was inhibited by the Act drove this result.

How do societies respond to adversity? After a negative shock, separate strands of research document either an increase in religiosity or a boost in scientific progress. In this paper, we show that both reactions can occur at the same time, driven by different individuals within society. The setting of our study is the 1918--1919 influenza pandemic in the United States. To measure religiosity, we construct a novel indicator based on the naming patterns of newborns. We measure scientific progress through the share of people in STEM occupations and the universe of granted patents. Exploiting plausibly exogenous county-level variation in exposure to the pandemic, we provide evidence that more affected counties become both more religious and more scientific. Within counties, we uncover heterogeneous responses: individuals from more religious backgrounds further embrace religion, while those from less religious backgrounds become more likely to choose a scientific occupation. Facing adversity widens the distance in religiosity between science-oriented individuals and the rest of the population and increases the polarization of religious beliefs.

How do patents influence innovation and growth? We leverage newly digitized data on examiners at the US Patent Office between 1919 and 1938 in a difference-in-differences framework. Newly appointed examiners grant 41% more patents to inventors residing close to their origin areas within their division. Patenting in other divisions, which the examiner does not oversee, increases by 10%. This effect is driven by divisions that are technologically closer to the examiner's division, indicating that patent protection presents substantial positive technology spillovers on innovation. We estimate large positive effects of patenting on local economic growth across multiple indicators.

This paper studies the distinctive pricing dynamics of durable goods and analyzes their implications for the conduct of monetary policy in a menu-cost economy. Using price microdata, I document the following new facts: (i) the dispersion of price changes in durables is higher than in nondurables; (ii) the frequency of price adjustment is countercyclical, however durable prices get relatively rigid in recessions; (iii) the dispersion of price changes is countercyclical for durables, and procyclical for nondurables. I develop a menu-cost model embedding durable consumption and calibrate it to match new and consolidated empirical evidence. I use the model to challenge the prevailing view holding that durable goods dampen the real effectiveness of monetary policy. I find that even though durable goods prices are relatively flexible, the model generates substantial monetary non-neutrality. Moreover, this paper puts forward a new channel whereby durable consumption can amplify the real effects of monetary policy. This result is driven by heterogeneous demand pass-through of aggregate shocks across sectors. Higher durable consumption enhances the sensitivity of nondurable output to interest rate shocks thus amplifying monetary non-neutrality.

Can racial discrimination harm innovation? We study this question using data on US inventors linked to population censuses in 1895-1925. Our novel identification strategy leverages plausibly exogenous variation in the timing of lynchings and the name of the victims. We find an immediate and persistent decrease in patents granted to inventors who share their names with the victims of lynchings, but only when victims are Black. We hypothesize that lynchings accentuate the racial content of the victim's name to patent examiners, who cannot observe the inventors' race from patent applications. We interpret these findings as evidence of discrimination by patent examiners and provide results against alternative mechanisms.

Natural disasters catalyze innovative activity. This paper asks whether industrial policy can direct this activity to generate innovation that mitigates their adverse consequences. We draw on two historical episodes: the great fires in Chicago (1871) and Boston (1872). In Chicago, the municipal authority forbade wooden constructions after the fire, while no such policy was enacted in Boston. We find that innovation, employment, and output of construction firms increased in both cities. In Chicago, however, these effects are concentrated in firms that operate in non-wood construction. In Boston, instead, they are diluted across all construction firms. In Chicago, we estimate positive spillover effects in sectors that were technically closer to non-wood construction, such as metallurgy and chemistry, while no such effect is present in Boston.

This paper examines the impact of sewing machines on female labor force participation, fertility, and marriage market outcomes. Historians regard sewing machines as a significant technical breakthrough affecting women's role at work and at home. We leverage industry-level exposure to sewing machines and novel data on sewing machine retailers in the United States. In a difference-in-differences design, we show that the diffusion of sewing machines between 1860 and 1880 substantially increased female labor force participation while fertility and marriages decreased. The effects of the sewing machines are vastly heterogeneous across income groups. Our results suggest that poor women drive the bulk of the increase in female labor force participation and fertility decline. Wealthy women, on the other hand, respond to the establishment of sewing machine retailers. This suggests that the impact of sewing machines as household appliances is concentrated at the top of the income distribution. Finally, we quantify large intergenerational spillovers of women's exposure to sewing machines.

Innovation by and for individuals from socio-economically disadvantaged groups is relatively under-provided. In this paper, we explore whether exposure to diversity through urban infrastructure directs innovation to target such groups. We assemble a new dataset listing the universe of bridges built in 20 major US cities between 1920 and 1940. We leverage cross-neighborhood variation in exposure to diversity through bridge construction in an individual-level difference-in-differences setting. We estimate a significant effect of exposure to Blacks on the number of Black-related patents. Importantly, we find that the effect is larger for inventors that reside in relatively less diverse neighborhoods. We interpret this result as novel evidence that exposure to diverse neighborhoods shifts the volume and the direction of innovation activity to target under-represented minority groups.

The mandate of intellectual property offices across the world is to increase the volume of innovation. This paper explores how patent fees influence patenting activity. In 1883, a reform decreased patent fees in England by 75%. Using the newly digitized universe of patents filed between 1853 and 1899 and linked to the individual-level population census, we document several facts. After 1883, (i) the volume of produced patents tripled; (ii) the average age of inventors decreased by 10%; (iii) the share of patents produced by women doubled; (iv) the share of patents produced by inventors in low- and mid-skill occupations increased; (v) the average quality of patents did not change, but (vi) the number of breakthrough patents increased; and (vii) the share of patents from inventors living in socio-economically disadvantaged areas increased. Overall, we conclude that more affordable patents increase the diversity of the inventor pool and facilitate patenting activity of high-impact innovations.

This paper examines the persistence of political preferences across generations and quantifies its contribution to political segregation. After the election of prominent government officials—such as the President, or state governors—their name becomes politically connoted. The name of an individual born close to an election year thus reflects the political preferences of their parent(s). I leverage this insight to construct and validate a new individual-level measure of intergenerational transmission of political preferences between 1865 and 1940. I find that political preferences are substantially persistent across generations: the son of a Republican (resp. Democrat) is five times more likely to be a Republican (resp. Democrat) than the son of a Democrat (resp. Republican). Individuals are more likely to sort in politically homogenous neighborhoods, thereby increasing political segregation.