We quantify the effect of deliberation on the decisions of US appellate courts. We estimate a model in which strategic judges communicate before casting their votes and then compare the probability of mistakes in the court with deliberation with a counterfactual of no communication. The model has multiple equilibria, and preferences and information parameters are only partially identified. We find that there is a range of parameters in the identified set—when judges tend to disagree ex ante or their private information is imprecise—in which deliberation can be beneficial; otherwise, deliberation reduces the effectiveness of the court.

We introduce a measure of the severity of violations of the revealed preference axioms, the money pump index (MPI). The MPI is the amount of money one can extract from a consumer who violates the axioms. It is also a statistical test for the hypothesis that a consumer is rational when behavior is observed with error. We present an application using a panel data set of food expenditures. The data exhibit many violations of the axioms. Mostly, the MPI for these violations is small. The MPI indicates that the hypothesis of consumer rationality cannot be rejected.

A new information aggregation mechanism (IAM), developed via laboratory experimental methods, is implemented inside Intel Corporation in a long-running field test. The IAM, incorporating features of pari-mutuel betting, is uniquely designed to collect and quantize as probability distributions dispersed, subjectively held information. IAM participants’ incentives support timely information revelation and the emergence of consensus beliefs over future outcomes. Empirical tests demonstrate the robustness of experimental results and the IAM’s practical usefulness in addressing real-world problems. The IAM’s predictive distributions forecasting sales are very accurate, especially for short horizons and direct sales channels, often proving more accurate than Intel’s internal forecast.