In reality, it is often groups rather than individuals that make decisions. In previous experiments, groups have frequently been shown to act differently from individuals in several ways. It has been claimed that inter-group interactions may be (1) more competitive, (2) more rational, or (3)...

In reality, it is often groups rather than individuals that make decisions. In previous experiments, groups have frequently been shown to act differently from individuals in several ways. It has been claimed that inter-group interactions may be (1) more competitive, (2) more rational, or (3)...

A typical empirical study involves choosing a sample, a research design, and an analysis path. Variation in such choices across studies leads to heterogeneity in results that introduce an additional layer of uncertainty not accounted for in reported standard errors and confidence intervals. We...