We identify the impact of local firm concentration on incumbent performance with a quasi natural experiment. When Germany was divided after World War II, many firms in the machine tool industry fled the Soviet occupied zone to prevent expropriation. We show that the regional location decisions...

There are two principal theories of why countries or regions trade: comparative advantage and increasing returns to scale. Yet there is virtually no empirical work that assesses the relative importance of these two theories in accounting for production structure and trade. We use a framework...

We organized business associations for the owner-managers of randomly selected young Chinese firms to study the effect of business networks on firm performance. We randomized 2,800 firms into small groups whose managers held monthly meetings for one year, and into a “no- meetings” control...

We document geographic concentration by both venture capital firms and venture capital-financed companies in three cities - San Francisco, Boston, and New York. We find that firms open new satellite offices based on the success rate of venture capital-backed investments in an area. Geography is...

We provide a general framework for the study of cascade effects created by interconnections between sectors, firms or financial institutions. Focusing on a multi sector economy linked through a supply network, we show how structural properties of the supply network determine both whether...

Whether the danger invoked is nuclear war or genetically modified foods, far more people in some countries than in others say they are afraid. Using data from six surveys, I show that the levels of reported fear of different dangers correlate strongly across both individuals and countries. I...

We develop a spatial model of energy exploitation where energy sources are differentiated by their geographic location and energy density. The spatial setting creates a scaling law that magnifies the importance of differences across energy sources. As a result, renewable sources twice as dense,...

Perhaps the most striking feature of "crowdfunding" is the broad geographic dispersion of investors in small, early-stage projects. This contrasts with existing theories that predict entrepreneurs and investors will be co-located due to distance-sensitive costs. We examine a crowdfunding setting...

We study how the employment effects of enterprise zones vary with their location, implementation, and administration, based on evidence from California. We use new establishment-level data and geographic mapping methods, coupled with a survey of enterprise zone administrators. Overall, the...

We simultaneously assess the contributions to productivity of three sources of research and development spillovers: geographic, technology and product-market proximity. To do this, we construct a new measure of geographic proximity that is based on the distribution of a firm's inventor locations...