Behavioral Social Choice, first published in 2006, looks at the probabilistic foundations of collective decision-making rules. The authors challenge much of the existing theoretical wisdom about social choice processes, and seek to restore faith in the possibility of democratic decision-making. In particular, they argue that worries about the supposed prevalence of majority rule cycles that would preclude groups from reaching a final decision about what alternative they prefer have been greatly overstated. In practice, majority rule can be expected to work well in most real-world settings. Furthermore, if there is a problem, they show that the problem is more likely to be one of sample estimates missing the majority winner in a close contest (e.g., Bush-Gore) than a problem about cycling. The authors also provide new mathematical tools to estimate the prevalence of cycles as a function of sample size and insights into how alternative model specifications can change our estimates of social orderings.
• Challenges existing wisdom (stemming from Arrow's Impossibility Theorem) that democratic decision-making is inherently flawed • Close link between theory and empirical applications, including data on real-world elections in US and Europe • New mathematical tools to estimate majority rule relationship from sample data
Part I. Probabilistic Models of Social Choice Behavior: 1. The lack of theoretical and practical support for majority cycles; 2. A general concept of majority rule; Part II. Applications of Probabilistic Models to Empirical Data: 3. On the model dependence versus robustness of social choice results; 4. Constructing majority preferences from subset choice data; Part III. A General Statistical Sampling and Bayesian Inference Framework: 5. Majority rule in a statistical sampling and Bayesian inference framework; 6. Conclusions and directions for future behavioral social choice research.