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...

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...