We investigate the speed at which clusters of invention for a technology migrate spatially following breakthrough inventions. We identify breakthrough inventions as the top one percent of US inventions for a technology during 1975-1984 in terms of subsequent citations. Patenting growth is...

This study tests the importance of Ricardian technology differences for international trade. The empirical analysis has three comparative advantages: including emerging and advanced economies, isolating panel variation regarding the link between productivity and exports, and exploiting...

High-skilled immigrants are a very important component of U.S. innovation and entrepreneurship. Immigrants account for roughly a quarter of U.S. workers in these fields, and they have a similar contribution in terms of output measures like patents or firm starts. This contribution has been...

In cross-sectional studies, countries with greater income inequality typically exhibit less support for government-led redistribution and greater acceptance of wage inequality (e.g., United States versus Western Europe). If individual nations evolve along this pattern, a vicious cycle could form...

We study the relationship between firm centralization and organizational reproduction in satellite locations. For decentralized firms, the ethnic compositions of inventors in satellite locations mostly resemble their host cities, with little link to the inventor composition of their parent...

Over the past half-century, while self-employment has consistently accounted for around one in ten of the United States workforce, its composition has changed. Since 1970, industries with high startup capital requirements have declined from 53% of self-employment to 23%. This same time period...

U.S. invention has become increasingly concentrated around major tech centers since the 1970s, with implications for how much cities across the country share in concomitant local benefits. Is invention becoming a winner-takes-all race? We explore the rising spatial concentration of patents and...

Networking and the giving and receiving of advice outside of one's own firm are important features of entrepreneurship and innovation. We study how immigrants and natives utilize the potential networking opportunities provided by CIC, formerly known as the Cambridge Innovation Center. CIC is...

Tech clusters like Silicon Valley play a central role for modern innovation, business competitiveness, and economic performance. This paper reviews what constitutes a tech cluster, how they function internally, and the degree to which policy makers can purposefully foster them. We describe the...

Immigrants account for about a quarter of US invention and entrepreneurship despite a policy environment that is not well suited for these purposes. This chapter reviews the US immigration policy environment that governs how skilled migrants move to America for employment-based purposes. We...