We study a vertically differentiated market where two firms simultaneously choose the quality and price of the good they sell and where consumers also care for the average quality of the goods supplied. Firms are composed of two factions whose objectives differ: one is maximizing profit while...

A feasible social state is irreducible if and only if, for any non-trivial partition of individuals with two groups, there exists another feasible social state at which every individual in the first group is equally well-off and someone strictly better-off. Competitive equilibria decentralize...

This paper assumes that groups of consumers in network markets can coordinate their choices when it is in their best interest to do so, and when coordination does not require communication. It is shown that multiple asymmetric networks can coexist in equilibrium if consumers have heterogeneous...

The random priority (random serial dictatorship) mechanism is a common method for assigning objects to individuals. The mechanism is easy to implement and strategy-proof. However this mechanism is inefficient, as the agents may be made all better off by another mechanism that increases their...

In incomplete information environments with transferable utility, efficient outcomes are generally implementable unless interim or ex post participation constraints are imposed on the problem. In this paper we show that linking a sufficiently large number of independent but possibly unrelated...

We study the problem of how to allocate a set of indivisible objects like jobs or houses and an amount of money among a group of people as fairly and as efficiently as possible. A particular constraint for such an allocation is that every person should be assigned with the same number of objects...