Nowadays many employers offer their employees the possibility of an insurance against too large losses in income when retiring or becoming disabled. This paper models the optimization problem of the employer when setting up such a so-called pension fund. not surprisingly, it turns out that the...

We consider a network economy in which economic agents are connected within a structure of value-generating relationships. Agents are assumed to be able to participate in three types of economic activities: autarkic self-provision; binary matching interactions; and multi-person cooperative...

We consider a relational economy in which economic agents participate in three types of relational economic activities: autarkic activities; binary matching activities; and plural cooperative activities. We introduce a stability notion and characterize stable interaction structures, both in the...

Limit core allocations are the ones that remain in the core of a replicated economy.An equivalent notion for economies with public goods is Schweizer s concept of club e ciency under a variable number of economic agents.We extend this notion to economies with goods that have a semi-public...

In this paper we axiomatically characterize two recursive procedures for defining a social group.The first procedure starts with the set of all individuals who define themselves as members of the social group, while the starting point of the second procedure is the set of all individuals who are...

Impersonal exchange has been a major driver of economic development. But transactors with no stake in maintaining an ongoing relationship have little incentive to honor deals. Therefore, all economies have developed institutions to support honest trade and realize the gains of impersonal...

Recent work by Kasher and Rubinstein (1997) considers the problem of group identification from a social choice perspective.These authors provide an axiomatic characterization of a liberal aggregator whereby the group consist of those and only those individuals each of which views oneself a...