The authors study the performance of the rational expectations hypothesis in multiperiod experimental markets with multiple assets. They find that the markets are generally inefficient from the point of view of full information aggregation. However, arbitrage relationships hold and it is not possible to detect the informational inefficiency by using some standard tests of market efficiency. These findings suggest that the lack of arbitrage opportunities and the failure of common tests to reject inefficiency are not sufficient to conclude that a market is informationally efficient.

We study the performance of the rational expectations hypothesis in multiperiod experimental markets with multiple assets. We find that the markets are generally inefficient from the point of view of full information aggregation. However, arbitrage relationships hold, and it is not possible to detect the informational inefficiency by using some standard tests of market efficiency. These findings suggest that the lack of arbitrage opportunities and the failure of common tests to reject inefficiency are not sufficient to conclude that a market is informationally efficient.

This paper characterizes conditions under which asset returns and consumption are consistent with risk‐averse preferences. It is shown that risk aversion is equivalent to “zero arbitrage” on a transformation of the payoff space. The implicit state prices which are dual to this no‐arbitrage condition can be interpreted as prices of “pure consumption hedges.” This zero‐arbitrage restriction implies the usual restrictions associated with nonsatiation. The analysis holds in both complete and incomplete market settings.

This paper characterizes conditions under which asset returns and consumption are consistent with risk-averse preferences. It is shown that risk aversion is equivalent to “zero arbitrage” on a transformation of the payoff space. The implicit state prices which are dual to this no-arbitrage condition can be interpreted as prices of “pure consumption hedges.” This zero-arbitrage restriction implies the usual restrictions associated with nonsatiation. The analysis holds in both complete and incomplete market settings.