Social networks, be it on the internet or in real life, facilitate information flows. We model this by giving agents incentives to link with others and receive information through those links. In many networks agents will value confirmation of the information they receive from others. Our paper...

The novelty of our model is to combine models of collective action on networks with models of social learning. Agents are connected according to an undirected graph, the social network, and have the choice between two actions: either to adopt a new behavior or technology or stay with the default...

We consider a co-evolutionary model of social coordination and network formation where agents may decide on an action in a 2x2 - coordination game and on whom to establish costly links to. We fi nd that a payo ff dominant convention is selected for a wider parameter range when agents may only...

We investigate the trade-off between the risk-sharing gains enjoyed by more interconnected firms and the costs resulting from an increased risk exposure. We find that when the shock distribution displays “fat” tails, extreme segmentation into small components is optimal, while minimal...

We investigate the scope for cooperation within a community engaged in repeated reciprocal interactions. Players seek the help of others and approach them sequentially according to some fixed order, that is, a ranking profile. We study the ranking profiles that are most effective in sustaining...

This paper studies a noncooperative model of network formation. Built upon the two-way flow model of Bala and Goyal (2000a), it assumes that information decay as it flows through each agent, and the decay is increasing and concave in the number of his links. This assumption results in the fact...

We develop a model of information exchange through communication and investigate its implications for information aggregation in large societies. An \textit{underlying state} determines payoffs from different actions. Agents decide which others to form a costly \textit{communication link} with,...

The paper discusses community enforcement in infinitely repeated, two-action games with local interaction and uncertain monitoring. Each player interacts with and observes only a fixed set of opponents, of whom he is privately informed. The main result shows that when beliefs about the...

This paper develops a simple model in which a social hierarchy emerges endogenously when agents form a network for complementary interaction (``activity''). Specifically, we assume that agents are ex ante identical and their best response activity, as well as their value function, increases...

We address the problem of a planner looking for the efficient network when agents play a network game with local complementarities and links are costly. We show that for general network cost functions, efficient networks belong to the class of Nested-Split Graphs. Next, we refine our results and...