Inventing modern invention: The professionalization of technological progress in the US
Over the course of the mid-19th and early 20th century, the US transformed from an agricultural economy to the frontier in technology. To study this transition, we digitize half a million pages of patent yearbooks that describe inventors, organizations and technologies on over 1.6M patents. We combine this with demographic information from US census records and information on corporate research from large-scale repeated surveys of industrial research labs. Our data reveal that in the early 1920s a new system of innovation — based on teamwork and engineers — started to rapidly replace the existing craftsmanship-based invention that had dominated innovation in the 19th century. We argue that this new system relied on an organizational innovation: industrial research labs. These labs supported high-skill teamwork, replacing the collaborations within families with professional ties in firms and industrial research labs. The systemic shift in innovation had far-reaching consequences: it changed the division of labor in invention, led to an explosion of novelty and teamwork, and reshaped the geography of innovation in the US.
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Tackling Discrepancies in Trade Data: The Harvard Growth Lab International Trade Datasets
Bilateral trade data informs foreign and domestic policy decisions, serves as a growth indicator, determines tariffs, and is the basis for financial and investment decisions for corporations. Accurate trade data translates into better decision-making. However, the raw bilateral trade data reported by UN Comtrade suffer from two structural problems: reporting differences between country partners and countries reporting in different product classification systems, which require product-level harmonization to compare data across countries. In this paper, we address these challenges by combining a mirroring technique and a data-driven concordance method. Mirroring reconciles importer and exporter differences by imputing country reliability scores and applying a weighted country-pair average to calculate the estimated trade value. We harmonize product classifications across vintages by calculating conversion weights that reflect a product’s market share. The resulting publicly available datasets mitigate issues in raw trade statistics, reducing reporting inconsistencies while maintaining product-level granularity across six decades.
Bridging the short-term and long-term dynamics of economic structural change
Economic development hinges on structural change, that is, transformations in what an economy produces. The field of economic complexity has investigated this process through two related but distinct branches: one studying how economies diversify, the other how the complexity of an economy is reflected in its output. However, a formal connection between these approaches, and their relationship to classic accounts of structural transformation (for example, from agriculture to manufacturing), remains unclear. Here we introduce a simple dynamical model that links these perspectives through one core idea: economies diversify preferentially into activities related to those they already do. Studying this model yields three main results: It generates quantities resembling economic complexity metrics, suggests these metrics summarize long-term structural change rather than directly infer an economy’s complexity, and reproduces stylized facts of development. Our framework formally connects the field’s conceptual strands, bridges short and long timescales of change, and adds granularity to classic descriptions of development.
The Coherence of US Cities
Diversified economies are critical for cities to sustain their growth and development, but they are also costly because diversification often requires expanding a city’s capability base. We analyze how cities manage this trade-off by measuring the coherence of the economic activities they support, defined as the technological distance between randomly sampled productive units in a city. We use this framework to study how the US urban system developed over almost two centuries, from 1850 to today. To do so, we rely on historical census data, covering over 600M individual records to describe the economic activities of cities between 1850 and 1940, as well as 8 million patent records and detailed occupational and industrial profiles of cities for more recent decades. Despite massive shifts in the economic geography of the United States over this 170-year period, average coherence in its urban system remains unchanged. Moreover, across different time periods, datasets, and relatedness measures, coherence falls with city size at the exact same rate, pointing to constraints to diversification that are governed by a city’s size in universal ways.
COVID-19 and emerging markets: A SIR model, demand shocks and capital flows
We quantify the macroeconomic effects of COVID-19 for a small open economy. We use a two-country framework combined with a sectoral SIR model to estimate the effects of collapses in foreign demand and supply. The small open economy (country one) suffers from domestic demand and supply shocks due to its own pandemic. In addition, there are external shocks coming from the rest of the world (country two). Aggregate exports of the small open economy decline when foreign demand goes down, and aggregate imports suffer from lockdowns in the rest of the world. We calibrate the model to Turkey. Our results show that the optimal policy, which yields the lowest output loss and saves the maximum number of lives, for the small open economy, is an early and globally coordinated full lockdown of 39 days.
The impact of return migration on employment and wages in Mexican cities
How does return migration from the US to Mexico affect local workers? Return migrants increase the local labor supply, potentially hurting local workers. However, having been exposed to a more advanced U.S. economy, they may also carry human capital that benefits non-migrants. Using an instrument based on involuntary return migration, we find that, whereas workers who share returnees’ occupations experience a fall in wages, workers in other occupations see their wages rise. These effects are, however, transitory and restricted to the city-industry receiving the returnees. In contrast, returnees permanently alter a city’s long-run industrial composition, by raising employment levels in the local industries that hire them.
Yet it Endures: The Persistence of Original Sin
Notwithstanding announcements of progress, “international original sin” (the denomination of external debt in foreign currency) remains a persistent phenomenon in emerging markets. Although some middle-income countries have succeeded in developing markets in local-currency sovereign debt and attracting foreign investors, they continue to hedge their currency exposures through transactions with local pension funds and other resident investors. The result is to shift the locus of currency mismatches within emerging economies but not to eliminate them. Other countries have limited original sin by limiting external borrowing, passing up valuable investment opportunities in pursuit of stability. We document these trends, analyzing regional and global aggregates and national case studies. Our conclusion is that there remains a case for an international initiative to address currency risk in low- and middle-income economies so they can more fully exploit economic development opportunities.
Horrible trade-offs in a pandemic: Poverty, fiscal space, policy, and welfare
We analyze how poverty and a country’s fiscal space impact policy and welfare in times of a pandemic. We introduce a subsistence level of consumption into a tractable heterogeneous agent framework, and use this framework to characterize optimal joint policies of a lockdown and transfer payments. In our model, a more stringent lockdown helps fighting the pandemic, but it also deepens the recession, which implies that poorer parts of society find it harder to subsist. This reduces their compliance with the lockdown, and may cause deprivation of the very poor, giving rise to an excruciating trade-off between saving lives from the pandemic and from deprivation. Transfer payments help mitigate this trade-off. We show that, ceteris paribus, the optimal lockdown is stricter in richer countries and the aggregate death burden and welfare losses smaller. We then consider a government borrowing constraint and show that limited fiscal space lowers the optimal lockdown and welfare, and increases the aggregate death burden during the pandemic. This is particularly true in societies where a larger fraction of the population is in poverty. We discuss evidence from the literature and provide reduced-form regressions that support the relevance of our main mechanisms. We finally discuss distributional consequences and the political economy of fighting a pandemic.
Productivity Gap and Inward FDI Spillovers: Theory and Evidence from China
This paper constructs a two-stage sequential game model to shed light on the spillover effect of inward FDI on the efficiency of domestic firms in host countries. Our model shows that, given an optimal joint-venture policy made by foreign firms, the impact of the spillover effect of inward FDI is contingent upon the productivity gap between the domestic firms and foreign ones. In particular, we demonstrate that the spillover effect of inward FDI varies negatively with the productivity gap between domestic low-productivity firms and foreign firms but works in the opposite way for high-productivity firms. This suggests that once the productivity gap widens, the entry of foreign firms will increase the efficiency of high-productivity firms but reduce the efficiency of low-productivity firms. In support of our theoretical model, we provide robust empirical results by using the dataset of annual survey of Chinese industrial enterprises.
Toward an empirical investigation of the long-term debt and financing deficit nexus: evidence from Chinese-listed firms
As the literature has studied the financing method of Chinese-listed firms for a long time, but with inconclusive indications, this research thus adopts non-financial Chinese-listed firms’ data from 2003 to 2015 to investigate the relationship between long-term debt financing and financing deficit. We pay particular attention to three channels (ownership concentration, market timing, and state ownership) that potentially affect the adoption of long-term debt financing when there is a financing deficit. The empirical analysis documents a positive relationship between financing deficit and changes in the long-term debt ratio in our sampled firms for both static and dynamic panel models. Moreover, among the three channels we show that state ownership has the strongest positive impact on the adoption of long-term debt financing, followed by ownership concentration, while the weakest channel is the market timing’s negative effect. In general, our empirical analysis finds that the important external financing method of long-term debt is most likely to be impacted by the state ownership aspect.