The acquisition and dispersion of information, a critical aspect of economic decisions, can occur through a network of agents (Jackson, 2009). Empirical and theoretical findings suggest that an efficient information dispersion network takes the form of a star: small numbers of agents gather information and distribute it to a large group. Despite these findings, controlled tests of this theory f...

This paper studies bilateral insurance schemes across networks of individuals. While transfers are based on social norms, each individual must have the incentive to abide by those norms, and so we investigate the structure of self-enforcing insurance networks. Network links play two distinct and possibly conflictual roles. First, they act as conduits for transfers. Second, they act as conduits ...

We study learning and influence in a setting where agents communicate according to an arbitrary social network and näıvely update their beliefs by repeatedly taking weighted averages of their neighbors’ opinions. A focus is on conditions under which beliefs of all agents in large societies converge to the truth, despite their näıve updating. We show that this happens if and only if the influenc...

We develop a new class of random-graph models for the statistical estimation of network formation that allow for substantial correlation in links. Various subgraphs (e.g., links, triangles, cliques, stars) are generated and their union results in a network. The challenge in estimating the frequencies with which subgraphs ‘truly’ form is that subgraphs can overlap and may also incidentally gener...

We investigate the impact of agent communication networks on prices in an artificial stock market. Networks with different centralization measures are tested for their effect on the volatility of prices. Trading strategies diffuse through the different network topologies, mimetic contagion arises through the adaptive behavior of the heterogeneous agents. Short trends may trigger cascades of buy...

Heterogeneity in Nash networks with two-way flow can arise due to differences in the following four variables: (i) the value of information held by players, (ii) the rate at which information decays as it traverses the network, (iii) the probability with which a link transmits information, and (iv) the cost of forming a link. Observe that the second and third forms of heterogeneity are also ins...

We analyze a team formation process that generalizes matching models and network formation models, allowing for overlapping teams of heterogeneous size. We define a weak concept of stability, called myopic team-wise stability, which extends to our setup the concept of pair-wise stability used in network formation models. Then we refine it in two ways: (i) through stochastic stability, where age...

We study a dynamic learning model in which heterogeneously connected Bayesian players choose between two activities: learning from one’s own experience (work) or learning from the experience of others (search). Players who work produce an inflow of information which is local and dispersed across the society. Players who search aggregate the information produced by others and facilitate its diff...

The acquisition and dispersion of information, a critical aspect of economic decisions, can occur through a network of agents (Jackson, 2009). Empirical and theoretical findings suggest that an efficient information dispersion network takes the form of a star: small numbers of agents gather information and distribute it to a large group. Controlled tests of this theory, however, have typically ...

Observational learning is typically examined when agents have precise information about their position in the sequence of play. We present a model in which agents are uncertain about their positions. Agents are allowed to have arbitrary ex-ante beliefs about their positions: they may observe their position perfectly, imperfectly, or not at all. Agents sample the decisions of past individuals an...