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....

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...

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...