The theoretical literature on platforms and network effects predicts that the initial growth and takeoff of a platform crucially depends on the market’s expectations of the future installed base. This paper tests this claim, reporting on a field experiment in which invitations to join a newly...

Digital platforms are increasingly the subject of regulatory scrutiny. In comparison to multiple competitors, a single platform may increase consumer welfare if network effects are large or may decrease welfare due to higher prices or reduction in platform variety. We study the net effect of...

This Chapter provides a survey of the economics literature on multi-sided platforms with particular focus on competition policy issues, including market definition, mergers, monopolization, and coordinated behavior. It provides a survey of the general industrial organization theory of...

Online markets reduce certain transaction costs related to global outsourcing. We focus on the role of verified work experience information in affecting online hiring decisions. Prior research shows that additional information about job applicants may disproportionately help or hinder...

We evaluate the consequences of narrow hospital networks in commercial health care markets. We develop a bargaining solution, Nash-in-Nash with Threat of Replacement, that captures insurers' incentives to exclude, and combine it with California data and estimates from Ho and Lee (2017) to...

The paper uses disaggregated data on asset holdings and liabilities to estimate a general equilibrium model where each institution determines the diversification and size of the asset and liability sides of its balance-sheet. The model endogenously generates two types of financial networks: (i)...

This paper studies how interest groups allocate campaign contributions when congressmen are connected by social ties. We establish conditions for the existence of a unique Nash equilibrium in pure strategies for the contribution game and characterize the associated allocation of the interest...

Using staggered entry of two dockless bikesharing firms, we find the entrant expands the market for the incumbent. The entry helps the incumbent to serve a greater number of trips, make more bike investment, achieve higher revenue per trip, improve bike utilization rate, and form a wider and...

In order to induce farmers to adopt a productive new agricultural technology, we apply simple and complex contagion diffusion models on rich social network data from 200 villages in Malawi to identify seed farmers to target and train on the new technology. A randomized controlled trial compares...

This paper studies how changes in deportation fear induced by the roll-out of Secure Communities (SC), a far-reaching immigration enforcement program, affected the demand for safety net programs in the United States. We estimate the spillover effect of SC on the take-up of federal means-tested...