This study explores the role of U.S. ethnic scientific and entrepreneurial communities for international technology transfer to their home countries. U.S. ethnic researchers are quantified through an ethnic-name database and individual patent records. International patent citations confirm knowledge diffuses through ethnic networks, and manufacturing output in foreign countries increases with an elasticity of 0.1–0.3 to stronger scientific integration with the U.S. frontier. Specifications exploiting exogenous changes in U.S. immigration quotas address reverse-causality concerns. Exercises further differentiate responses by development stages in home countries. Ethnic technology transfers are particularly strong in high-tech industries and among Chinese economies.

This article documents the fact that ventures funded by two successful angel groups experience superior outcomes to rejected ventures: They have improved survival, exits, employment, patenting, Web traffic, and financing. We use strong discontinuities in angel-funding behavior over small changes in their collective interest levels to implement a regression discontinuity approach. We confirm the positive effects for venture operations, with qualitative support for a higher likelihood of successful exits. On the other hand, there is no difference in access to additional financing around the discontinuity. This might suggest that financing is not a central input of angel groups.

This study evaluates the impact of high-skilled immigrants on U.S. technology formation. We use reduced-form specifications that exploit large changes in the H-1B visa program. Higher H-1B admissions increase immigrant science and engineering (SE) employment and patenting by inventors with Indian and Chinese names in cities and firms dependent upon the program relative to their peers. Most specifications find limited effects for native SE employment or patenting. We are able to rule out displacement effects, and small crowding-in effects may exist. Total SE employment and invention increases with higher admissions primarily through direct contributions of immigrants. (c) 2010 by The University of Chicago. All rights reserved.

We examine entrepreneurship and creative destruction following US banking deregulations using US Census Bureau data. US banking reforms brought about exceptional growth in both entrepreneurship and business closures. Most of the closures, however, were the new ventures themselves. Although we find evidence for the standard story of creative destruction, the most pronounced impact was a massive increase in churning among new entrants. We argue that creative destruction requires many business failures along with the few great successes. The successes are difficult to identify ex ante, which is why democratizing entry is an important trait of well-functioning capital markets.

We study the impact of skilled immigrants on the employment structures of US firms using matched employer-employee data. Unlike most previous work, we use the firm as the lens of analysis to account for greater heterogeneity and the fact that many skilled immigrant admissions are driven by firms themselves (e.g., the H-1B visa). OLS and IV specifications show rising overall employment of skilled workers with increased skilled immigrant employment by the firm. Employment expansion is greater for young natives than for their older counterparts. The departure rates for older workers relative to younger workers appear highest for those in STEM occupations.

This article documents the fact that ventures funded by two successful angel groups experience superior outcomes to rejected ventures: They have improved survival, exits, employment, patenting, Web traffic, and financing. We use strong discontinuities in angel- funding behavior over small changes in their collective interest levels to implement a regression discontinuity approach. We confirm the positive effects for venture operations, with qualitative support for a higher likelihood of successful exits. On the other hand, there is no difference in access to additional financing around the discontinuity. This might suggest that financing is not a central input of angel groups.

We model spatial clusters of similar firms. Our model highlights how agglomerative forces lead to localized, individual connections among firms, while interaction costs generate a defined distance over which attraction forces operate. Overlapping firm interactions yield agglomeration clusters that are much larger than the underlying agglomerative forces themselves. Empirically, we demonstrate that our model’s assumptions are present in the structure of technology and labor flows within Silicon Valley. Our model further identifies how the lengths over which agglomerative forces operate influence the shapes and sizes of industrial clusters; we confirm these predictions using variations across patent technology clusters.

We build a tractable growth model in which multiproduct incumbents invest in internal innovations to improve their existing products, while new entrants and incumbents invest in external innovations to acquire new product lines. External and internal innovations generate heterogeneous innovation qualities, and firm size affects innovation incentives. We analyze how different types of innovation contribute to economic growth and the role of the firm size distribution. Our model aligns with many observed empirical regularities, and we quantify our framework with Census Bureau and patent data for US firms. Internal innovation scales moderately faster with firm size than external innovation.

The firm is almost entirely absent from models of immigration, and yet firms play a central role for high-skilled immigration. The H-1B visa program, for example, is a firm-sponsored entry where firms are responsible for every stage: from identifying the immigrant, to employing them, to filing for permanent residency on behalf of the immigrant. This central role of firms for high-skilled immigration suggests the traditional lens for evaluating the impact of immigration on natives through local area labor markets or national age-education approaches may miss important dynamics. We analyze the employment and wage trajectories of high-skilled workers born in America when a high-skilled immigrant arrives at their work site. We use linked employer-employee data during the 1995-2008 period from the Census Bureau for this exercise, which identifies the immigration status and country-of-birth of workers. We follow the subsequent career path of workers after high-skilled immigration occurs to the employee's work site both within firms (e.g., changes in employee salary, relocation to other sites) and across firms (e.g., movements to new jobs or out of workforce, long-term salary adjustments). The richness and depth of the Census Bureau data allow for multiple comparison points: selection on observables (e.g., age, tenure, salary levels and recent growth), varying immigration treatments across different work sites for the same firm for otherwise comparable employees, and (for a subset of cases and short time period at the end of our sample) randomization in H-1B admission lotteries.