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Deroïan
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Îlot Bernard du Bois
Publications
We consider a model of interdependent efforts, with linear interaction and lower bound on effort. Our setting encompasses asymmetric interaction and heterogeneous agents’ characteristics. We examine the impact of a rise of cross-effects on aggregate efforts. We show that the sign of the comparative static effects is related to a condition of balancedness of the interaction. Moreover, we point out that asymmetry and heterogeneous characteristics are sources of non-monotonic variation of aggregate efforts.
We examine the impact of informal risk sharing on risk taking incentives when transfers are organized through a social network. A bilateral partial sharing rule satisfies that neighbors share equally a part of their revenue. In such a society, correlated technologies generate interdependent risk levels. We obtain three findings. First, there is a unique and interior Nash-equilibrium risk profile, and it is in general differentiated and related to the Bonacich measure of the risk sharing network. Second, more revenue sharing enhances risk taking on average, although some agents may lower their risk level. Last, we find that under investment might often be observed.
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 in order to reduce the social dilemma.
We study the formation of a directed communication network in which agents distribute a fixed amount of resource over links. Indirect benefits transit through the path maximizing the product of link strength. In this environment, the wheel architecture is shown to be both the unique efficient and the unique Nash architecture.
Firms raise cost-reducing alliances before competing with each other, but cannot fully appropriate the shared knowledge. When spillovers disseminate through the network of alliances, link formation enables firms to capture more spillovers, but by doing so they become intermediary in the spreading of spillovers to other firms. This leads to the emergence of asymmetric networks.
We study rival firms' incentives in quality-improving Research and Development (R&D) networks. The analysis stresses the role of free riding associated to collaboration and three major consequences emerge: R&D efforts decrease with the number of partners, networks of alliances are over-connected as compared to the social optimum and the profitmaximizing number of alliances is possibly non monotonic (decreasing then increasing) with respect to inverse measure of product differentiation.
We study the formation of a communication network under perfect foresight. We show the existence of a non-monotonic relationship between the cost of link formation and the total number of links created in stable networks. This result enhances a dilemma between stable and efficient networks. Copyright Springer 2006
In a vertically differentiated oligopoly, firms raise cost-reducing alliances before competing with each other. It is shown that heterogeneity in quality and in cost functions reduces individual incentives to form links. Furthermore, both differentiated Cournot and Bertrand competition qualitatively similar incitations to form alliances.
We explore collective behaviors in a deterministic mode of interacting agents. We relate unanimity of diversity to the structura conditions of the interaction network.
No abstract is available for this item.