We show in this paper how, in a model of assets exchange in complete competitive markets, heterogeneity of the agent’s sub jective probabilities generates aggregate expenditures for Arrow-Debreu securities that have the gross substitutability property, with the consequences that competitive...

Ascending price auctions typically involve a single price path with buyers paying their final bid price. Using this traditional definition, no ascending price auction can achieve the Vickrey-Clarke-Groves (VCG) outcome for general private valuations in the combinatorial auction setting. We relax...

Individuals exchange contracts for the deliveryof commodities in competitive markets and, simultaneously, act strategically; actions affect utilities across individuals directlyor through the payoffs of contracts. This encompasses economies with asymmetric information. Nash-Walras equilibria...

Markets are incomplete when the assets available to the agents do not span the space of future contingencies. Efficiency is then assessed by the weak criterion of "constrained efficiency" (efficiency relative to the set of allocations compatible with the asset structure). That criterion requires...

For an overlapping generations economy with varying life-cycle productivity, non-stationary endowments, continuous time starting at _∞ (hence allowing for full anticipation), constant-returns-to-scale production and CES utility we fully characterise equilibria where output is higher than...

The main result is that the golden rule equilibrium (GRE) is Pareto optimal (in the classical sense) in an overlapping generations (OG) model with constant-returns-to-scale production, transfers, arbitrary life-time productivity and CES instantaneous felicity. In addition, we extend Cass and...

In an exogenous-growth economy with overlapping generations (OG) we analyse local stability of the balanced growth equilibria with respect to perturbations of consumption endowments, thought of as the "monetised" value of a government policy to individuals. We show that perturbed economies have...

At a Nash - Walras equilibrium, individuals exchange commodities competitively, and, simultaneously, they interact strategically. Under standard assumptions, NashWalras equilibria exist, equilibrium profiles of actions are, typically, determinate but Pareto suboptimal, though not constrained...

We analyse the consequences of an increase of information (say as a consequence of the internet), on the equilibrium of a pure exchange economy with n goods and m agents. We assume that such an increase modifies the characteristics of goods la Lancaster and has a positive effect on utility. We...

The generic existence of competitive equilibria when the asset market is incomplete extends to economies with restricted participation.