Suckers Are Born but Markets Are Made: Individual Rationality, Arbitrage, and Market Efficiency on an Electronic Futures Market

The Iowa Electronic Markets are specially designed futures markets that appear to aggregate information efficiently to predict events such as election outcomes. Yet, in theory, perfect information aggregation is impossible. Further, the markets are populated by a nonrepresentative sample of mistake-prone and biased traders. That is, traders are prone to the behavioral anomalies predicted by behavioral finance. How can this be reconciled with...