We show that, in a two-period economy with uncertainty in the second period, if an allocation is Pareto optimal for a given set of beliefs and remains optimal when these beliefs are changed, then the set of optimal allocations of the two economies must actually coincide. We identify equivalence classes of beliefs giving rise to the same set of Pareto optimal allocations. Journal of Economic Lit...

We analyze an exchange economy in which (i) all commodities except money are indivisible, (ii) agents' preferences can be described by a reservation value for each bundle of indivisible objects, and (iii) all agents are price-takers. We obtain a necessary and sufficient condition under which market clearing prices exist. Implications for market mechanisms are discussed. Journal of Economic Lite...

The distributions of income and wealth in countries across the world are found to possess some robust and stable features independent of the specific economic, social and political conditions of the countries. We discuss a few physics-inspired multiagent dynamic models along with their microeconomic counterparts, that can produce the statistical features of the distributions observed in reality...

We argue that, in exchange economies, various versions of the bargaining set cannot be implemented in Nash equilibrium. We then propose an extensive form mechanism that exactly implements the Aumann–Davis–Maschler bargaining set in subgame perfect equilibrium. The mechanism corresponds closely to the description of the bargaining set and respects feasibility in and out of equilibrium. Journal o...

We show the robustness of the Walrasian result obtained in models of bargaining in pairwise meetings. Restricting trade to take place only in pairs, most of the assumptions made in the literature are dispensed with. These include assumptions on preferences (differentiability, monotonicity, strict concavity, bounded curvature), on the set of agents (dispersed characteristics) or on the consumpti...

We consider a continuum economy with infinitely many commodities and show that, for any positive =, the core of the economy coincides with the set of allocations which are not blocked by any coalition with measure less than =. Actually, our main result is an extension of Grodal's (1972, Econometrica 40, 581 583) result and, therefore, Schmeidler's (1972, Econometrica 40, 579 580) result to econ...

We present a General Equilibrium model with incomplete markets in which assets pay in units of a single good. In our model, agents are constrained to negotiate the same amount of assets at different states of the world. Differently from the standard result of economies with real assets, our model shows the existence of real indeterminacy. The presence of multiple equilibria raises issues relate...

In the present paper, the issue of the existence of optimal barter steady states is addressed in a stationary overlapping generations model with many commodities and many different long-lived consumers. A general characterization of the individual endowments leading to an optimal barter steady state is obtained. The result, which is a generalization of Benveniste and Cass (1986), is obtained as...

This introduces the symposium on sunspots and lotteries. Two stochastic generalequilibrium concepts, sunspot equilibrium (SE) and lottery equilibrium (LE), are compared. It is shown that, for some general, pure-exchange economies which allow for consumption nonconvexities or moral hazards, the set of LE allocations is equivalent to the set of SE allocations provided that the randomizing device ...