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Many epistemologists have argued that there is some degree of independence between individual and collective reliability. The question, then, is: To what extent are the two independent of each other? And in which contexts do they come apart? In this paper, I present a new case confirming the independence between individual and collective reliability optimization. I argue that, in voting groups, optimizing individual reliability can conflict with optimizing collective reliability. This can happen even if various conditions are held constant, such as: the evidence jurors have access to, the voting system, the number of jurors, some independence conditions between voters, and so forth. This observation matters in many active debates on, e.g., epistemic dilemmas, the wisdom of crowds, independence theses, epistemic democracy, and the division of epistemic labour. [ABSTRACT FROM AUTHOR]

Adding candidates to a one-dimensional common-interest voting model, this paper shows that catering to centrist voters can lower social welfare. The electoral benefit of doing so is weak, so candidates polarize substantially in equilibrium, resolving a long-standing empirical puzzle. [ABSTRACT FROM AUTHOR]

In this spatial model of common-value elections, votes convey citizens' private opinions regarding which policies are socially optimal, and the winning candidate utilizes this information in choosing policy. In equilibrium, large margins of victory convey mandates for candidates to make bold policy changes. To communicate extreme policy views, citizens support extreme parties that may be unlikely to win office. To convey moderate views, citizens deliberately abstain from voting, thereby avoiding the signaling voter's curse of encouraging overextremism. In large elections, mandates can identify the optimal policy from an entire continuum, thereby greatly strengthening Condorcet's (1785) classic “jury” theorem. Behavioral patterns are consistent with otherwise puzzling empirical features of elections, and can also apply to other political activities, such as public protests or writing letters to elected officials. [ABSTRACT FROM AUTHOR]

This article analyzes participation and information aggregation in a common-value election with continuous private signals. In equilibrium, some citizens ignore their private information and abstain from voting, in deference to those with higher-quality signals. Even as the number of highly informed peers grows large, however, citizens with only moderate expertise continue voting, so that voter participation remains at realistic levels (e.g. 50 to 60 percent, for simple examples). The precise level of voter turnout, along with the margin of victory, are determined by the distribution of expertise. Improving a voter's information makes her more willing to vote, consistent with a growing body of empirical evidence, but makes her peers more willing to abstain, providing a new explanation for various empirical patterns of voting. Equilibrium participation is optimal, even though the marginal voter may have very little (e.g. below-average) expertise, and even though nonvoters' information is not utilized. [ABSTRACT FROM AUTHOR]

Condorcet’s jury theorem provides a possible explanation for the success of democracies relative to other forms of government. In its modern form, the jury theorem predicts that majority decisions are well informed, because they are based upon far more information than possessed by any single individual. On the other hand, it is evident that democratic politicians and policies are not always as good as the jury theorem implies they should be. This paper uses simulated elections to explore the power and limitations of majority rule as an estimator of candidate quality or policy effectiveness. The simulations demonstrate that slightly informed voters can make very accurate choices among candidates using majority rule. However, as the ratio of slightly informed voters relative to ignorant voters falls, the accuracy of majority decisions declines. The latter implies that institutions, policies, and technologies that promote the dissemination of information also tend to improve the efficiency of democratic governance. [ABSTRACT FROM AUTHOR]

Group decision making is commonly used injuries, businesses, and in politics to increase the informational basis for a decision and to improve judgment accuracy. Recent work on generalizing Condercet's jury theorem provides a compelling justification for using groups in this manner. But these theories rely on a model of the individual as an optimal Bayesian decision maker. Do groups effectively aggregate information when the individuals arc the flawed. non-Bayesian decision makers that actually populate acting groups? We first survey the evidence that individuals systematically violate Bayes' theorem under certain conditions. We then report two experiments designed to test whether individuals follow Bayesian reasoning and whether groups are able to overcome biased individual information processing. The experiments show that under certain conditions, with extreme probabilities and with signals that vary in diagnositicity, that individual accuracy actually deteriorates as information increases. For certain problems. majority rule effectively aggregates individual information. For the most difficult problems. majority rule fails to attenuate individual bias. The implications of these findings for research on individual and group judgment are discussed. [ABSTRACT FROM AUTHOR]