Technological progress builds upon itself, with the expansion of invention in one domain propelling future work in linked fields. Our analysis uses 1.8 million U.S. patents and their citation properties to map the innovation network and its strength. Past innovation network structures are...

We study the relationship between ethnicity, occupational choice, and entrepreneurship. Immigrant groups in the United States cluster in specific business sectors. For example, the concentration of Korean self-employment in dry cleaners is 34 times greater than other immigrant groups, and...

We study stable matchings on exogenously given or endogenously formed bipartite graphs that reflect constraints on matching. The effects of a change of the exogenously given graph (constraints) are investigated. Specifically, we examine to what extent individuals gain or lose from relaxing...

We present a multi-country theory of economic growth in which countries are connected by a network of mutual knowledge exchange. Knowledge in any country depends on the human capital of the countries it exchanges knowledge with. The diffusion of knowledge throughout the world explains a period...

Government or company decisions on whom to hire are mostly delegated to politicians, public sector officials or human resources and procurement managers. Due to anti-corruption laws, agents cannot sell contracts or positions that they are delegated to decide upon. Even if bribing is ruled out,...

This paper defines isomorphism for network formation that is not mathematically isomorphic. Once the pattern of network formation is characterized, one can test for (i) location fixed effects, (ii) heterogeneity, (iii) private information allowing for long-term contracts. The paper provides...