This paper analyzes statistical issues arising from networks based on non-representative samples of the population. We first characterize the biases in both network statistics and estimates of network effects under non-random sampling theoretically and numerically. Sampled network data...

This paper presents and structurally estimates a model of endogenous network formation and legislative activity of career-motivated politicians. Employing data on socialization and legislative effort of members of the 105th-110th U.S. Congresses, our model reconciles a set of empirical...

Social and economic networks are ubiquitous, serving as contexts for job search, technology diffusion, the accumulation of human capital and even the formulation of norms and values. The systematic empirical study of network formation - the process by which agents form, maintain and dissolve...

We develop a theoretical model of security investments in a network of interconnected agents. Network connections introduce the possibility of cascading failures due to an exogenous or endogenous attack depending on the profile of security investments by the agents. The general presumption in...

We develop and analyze a tractable empirical model for strategic network formation that can be estimated with data from a single network at a single point in time. We model the network formation as a sequential process where in each period a single randomly selected pair of agents has the...

We develop a model of informal financial networks and present corroborating evidence by studying the role of professional property brokers in the U.S. commercial real estate market. Our model demonstrates how service intermediaries, who do not supply finance themselves, can facilitate their...

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...

Many economic activities are embedded in networks: sets of agents and the (often) rivalrous relationships connecting them to one another. Input sourcing by firms, interbank lending, scientific research, and job search are four examples, among many, of networked economic activities. Motivated by...

We study factors influencing individuals' decisions to purchase Citibank stock during the 1920s. Citibank stock had a very high price per share and was only an investment option for wealthy people. The willingness to own shares was encouraged by proximity to New York, but constraints related to...

We explore the links between social capital and labor market networks at the neighborhood level. We harness rich data taken from multiple sources, including matched employer-employee data with which we measure the strength of labor market networks, data on behavior such as voting patterns that...