The overlapping expectations and the collective absence of arbitrage conditions introduced in the economic literature to insure existence of Pareto optima and equilibria with short-selling when investors have a single belief about future returns, is reconsidered. Investors use measures of risk....

The theory of existence of equilibrium with short-selling is reconsidered under risk and ambiguity modelled by risk averse variational preferences. No-arbitrage conditions are given in terms of risk adjusted priors. A sufficient condition for existence of efficient allocations is the overlapping...

In this paper we first prove an equilibrium existence theorem for finite dimensional economies with unbounded below consumption sets. We only assume that the individually rational utility set is compact and use the demand approach instead of the standard Negishi's approach. We next compare the...

The theory of existence of equilibrium with short-selling is reconsidered under risk and ambiguity modelled by risk averse variational preferences. A sufficient condition for existence of efficient allocations is that the relative interiors of the risk adjusted sets of expectations overlap. This...

In finite dimensional economies, it was proven by Werner [Werner, J., 1987. Arbitrage and the existence of competitive equilibrium. Econometrica 55, 1403–1418.], that if there exists a no-arbitrage price (equivalently, under standard assumptions on agents' utilities, if aggregate demand exists...