Intertemporal efficiency does not imply a common price forecast

Abstract

Do price forecasts of rational economic agents need to coincide in perfectly competitive complete markets? To address this question, we define an efficient temporary equilibrium (ETE) within the framework of a two period economy. Although an ETE allocation is intertemporally efficient and is obtained by perfect competition, it can arise without the agents forecasts being coordinated on a perfect foresight price. We show that there is a one dimensional set of such Pareto efficient allocations for generic endowments.