We provide existence results in a game with local spillovers where the payoff function satisfies both convexity and the strategic substitutes property. We show that there always exists a stable pairwise network in this game, and provide a condition which ensures the existence of pairwise equilibrium networks. Moreover, our existence proof allows us to characterize a pairwise equilibrium of thes...

We present a model of directed communication network with endogenous link strength. Agents are endowed with a fixed amount of resource which they can distribute over links. They obtain indirect benefit by the path maximizing the product of link strength. In this environment, the wheel architecture is shown to be not only the unique efficient architecture but also the unique Nash architecture. J...

This article explores individual incentives to produce information on communication networks. In our setting, efforts are strategic complements along communication paths with convex decay. We analyze Nash equilibria on a set of networks which are unambiguous in terms of centrality. We first characterize both dominant and dominated equilibria. Second, we examine the issue of social coordination ...

This paper uses a mechanism design framework to characterize how an intermediary can design profit-maximizing matching markets when agents have private information about their quality. When match surpluses are supermodular, sufficient conditions are provided that ensure positive assortative matching is profit maximizing. Under these conditions, two-sided position auctions are characterized that...

In this paper, we analyze the cost allocation problem when a group of agents or nodes have to be connected to a source, and where the cost matrix describing the cost of connecting each pair of agents is not necessarily symmetric, thus extending the well-studied problem of minimum cost spanning tree games, where the costs are assumed to be symmetric. The focus is on rules which satisfy axioms re...

In this paper, we analyze the cost allocation problem when a group of agents or nodes have to be connected to a source, and where the cost matrix describing the cost of connecting each pair of agents is not necessarily symmetric, thus extending the well-studied problem of minimum cost spanning tree games, where the costs are assumed to be symmetric. The focus is on rules which satisfy axioms re...

This paper considers the formation of risk-sharing networks. Following empirical findings, we build a model where pairs form links, but a population cannot coordinate links. As a benchmark, individuals commit to share monetary holdings equally with linked partners. We find efficient networks can (indirectly) connect all individuals and involve full insurance. But equilibrium networks connect fe...

Social network formation models are often compared by their network structures, which satisfy specific equilibrium or welfare properties. Here, we concentrate on welfare criteria and define properties of utility function which are causal for certain network structures. We hope the identification of different properties of utility function will enhance the understanding of the relationship of di...

Heterogeneity in Nash networks can arise due to differences in the following four variables: (i) the value of information held by agents, (ii) the rate at which information decays or loses its value as it traverses the network, (iii) the probability with which a links transmits information, and (iv) the cost of forming a link. In this paper we examine Nash networks, efficient networks and the e...

We study a simple model of a population of agents whose interaction network co-evolves with knowledge diffusion and accumulation. Diffusion takes place along the current network and, reciprocally, network formation depends on the knowledge profile. Diffusion makes neighboring agents tend to display similar knowledge levels. On the other hand, similarity in knowledge favors network formation. Th...