This monograph studies multi-member households or, more generally, socio-economic groups from a purely theoretical perspective and within a general equilibrium framework, in contrast to a sizeable empirical literature. The approach is based on the belief that households, their composition,...

We consider competitive markets for multiple commodities with endogenous formation of one- or two-person households. Within each two-person household, externalities from the partner's commodity consumption and unpriced actions are allowed. Each individual has two types of traits: observable...

We study the allocation of commodities through a two-stage hierarchy of competitive markets. Groups or countries trade at global prices while individuals within a group trade at local prices. We identify the free trade and the autarky equilibrium as polar cases. We show that no other two-stage...

We propose a formal concept of the power of voice in the context of a simple model where individuals form groups and trade in competitive markets. Individuals use outside options in two different ways. Actual outside options reflect the possibility to exit or to join other existing groups....