We study cost sharing problems where gains from cooperation can come from the presence of other agents, such as when agents share their technologies. A simple model is built, where economies of scale are eliminated in order to study this effect. We use as the key axiom the property that, if an...

We examine network problems where agents have to be connected to a source in order to obtain goods, and in which costs on different arcs are a function of the flow of goods. When all cost functions are concave, the resulting game might have an empty core. We introduce a set of problems with...

We consider an extension of minimum cost spanning tree (mcst) problems where some agents do not need to be connected to the source, but might reduce the cost of others to do so. Even if the cost usually cannot be computed in polynomial time, we extend the characterization of the Kar solution...

Minimum cost spanning tree (mcst) problems try to connect agents efficiently to a source when agents are located at different points in space and the cost of using an edge is fixed. We introduce a new cost sharing solution that always selects a point in the core and that is more responsive to...

Minimum cost spanning tree problems connect agents efficiently to a source with the cost of using an edge fixed. We revisit the dispute between the Kar and folk solutions, two solution concepts to divide the common cost of connection based on the Shapley value. We introduce a property called...

This paper studies matching markets in the presence of middlemen. In our framework, a buyer–seller pair may either trade directly or use the services of a middleman; and a middleman may serve multiple buyer–seller pairs. For each such market, we examine the associated TU game. We first show...