Majority rules: how good are we at aggregating convergent opinions?

Mandevillian vices

Bernard Mandeville argued that traits that have traditionally been seen as detrimental or reprehensible, such as greed, ambition, vanity, and the willingness to deceive, can produce significant social goods. He went so far as to suggest that a society composed of individuals who embody these vices would, under certain constraints, be better off than one composed only of those who embody the virtues of self-restraint. In the twentieth century, Mandeville's insights were taken up in economics by John Maynard Keynes, among others. More recently, philosophers have drawn analogies to Mandeville's ideas in the domains of epistemology and morality, arguing that traits that are typically understood as epistemic or moral vices (e.g. closed-mindedness, vindictiveness) can lead to beneficial outcomes for the groups in which individuals cooperate, deliberate, and decide, for instance by propitiously dividing the cognitive labor involved in critical inquiry and introducing transient diversity. We argue that mandevillian virtues have a negative counterpart, mandevillian vices, which are traits that are beneficial to or admirable in their individual possessor, but are or can be systematically detrimental to the group to which that individual belongs. Whilst virtue ethics and epistemology prescribe character traits that are good for every moral and epistemic agent, and ideally across all situations, mandevillian virtues show that group dynamics can complicate this picture. In this paper, we provide a unifying explanation of the main mechanism responsible for mandevillian traits in general and motivate the case for the opposite of mandevillian virtues, namely mandevillian vices.

Sensitivity to Evidential Dependencies in Judgments Under Uncertainty

According to Bayesian models of judgment, testimony from independent informants has more evidential value than dependent testimony. Three experiments investigated learners' sensitivity to this distinction. Each experiment used a social version of the balls‐and‐urns task, in which participants judged which of two urns was the most likely source of evidence presented by multiple informants. Informants either provided independent testimony based solely on their own observations or dependent‐sequential testimony that considered the testimonies of previous informants. Although participants updated their beliefs with additional evidence, this updating was generally insensitive to evidential dependency (Experiments 1 and 2). A notable exception was when individuals were separated according to their beliefs about the relative value of independent and sequential evidence. Those who viewed independent evidence as having greater value subsequently gave more weight to independent testimony in the balls‐and‐urns task (Experiment 3), in line with the predictions of a Bayesian model. Our findings suggest that only a minority of individuals conform to Bayesian predictions in the relative weighting of independent and dependent evidence in judgments under uncertainty.

Overcoming Individual Limitations Through Distributed Computation: Rational Information Accumulation in Multigenerational Populations

Many of the computational problems people face are difficult to solve under the limited time and cognitive resources available to them. Overcoming these limitations through social interaction is one of the most distinctive features of human intelligence. In this paper, we show that information accumulation in multigenerational social networks can be produced by a form of distributed Bayesian inference that allows individuals to benefit from the experience of previous generations while expending little cognitive effort. In doing so, we provide a criterion for assessing the rationality of a population that extends traditional analyses of the rationality of individuals. We tested the predictions of this analysis in two highly controlled behavioral experiments where the social transmission structure closely matched the assumptions of our model. Participants made decisions on simple categorization tasks that relied on and contributed to accumulated knowledge. Success required these microsocieties to accumulate information distributed across people and time. Our findings illustrate how in certain settings, distributed computation at the group level can pool information and resources, allowing limited individuals to perform effectively on complex tasks.

Blurb: Many of the problems people face are difficult to solve under the limited time and resources available to them. We show that individuals can overcome these limitations by following a simple social learning heuristic that yields distributed Bayesian inference at the population level. We test our model in two large behavioral experiments, comparing observed knowledge accumulation with the Bayesian ideal in multigenerational microsocieties.

“Worse Than What I Read?” The External Effect of Review Ratings on the Online Review Generation Process: An Empirical Analysis of Multiple Product Categories Using Amazon.com Review Data

In this paper, we study the online consumer review generation process by analyzing 37.12 million online reviews across nineteen product categories obtained from Amazon.com. This study revealed that the discrepancy between ratings by others and consumers’ post-purchasing evaluations significantly influenced both the valence and quantity of the reviews that consumers generated. Specifically, a negative discrepancy (‘worse than what I read’) significantly accelerates consumers to write negative reviews (19/19 categories supported), while a positive discrepancy (‘better than what I read’) accelerates consumers to write positive reviews (16/19 categories supported). This implies that others’ ratings play an important role in influencing the review generation process by consumers. More interestingly, we found that this discrepancy significantly influences consumers’ neutral review generation, which is known to amplify the effect of positive or negative reviews by affecting consumers’ search behavior or the credibility of the information. However, this effect is asymmetric. While negative discrepancies lead consumers to write more neutral reviews, positive discrepancies help reduce neutral review generation. Furthermore, our findings provide important implications for marketers who tend to generate fake reviews or selectively generate reviews favorable to their products to increase sales. Doing so may backfire on firms because negative discrepancies can accelerate the generation of objective or negative reviews.

Ecological Values Theory: Beyond Conformity, Goal-Seeking, and Rule-Following in Action and Interaction

Values have long been considered important for psychology but are frequently characterized as beliefs, goals, rules, or norms. Ecological values theory locates them, not in people or in objects, but in ecosystem relationships and the demands those relationships place on fields of action within the system. To test the worth of this approach, we consider skilled coordination tasks in social psychology (e.g., negotiating disagreements, synchrony and asynchrony in interactions, and selectivity in social learning) and perception-action (e.g., driving vehicles and carrying a child). Evidence suggests that a diverse array of values (e.g., truth, social solidarity, justice, flexibility, safety, and comfort) work in a cooperative tension to guide actions. Values emerge as critical constraints on action that differ from goals, rules, and natural laws, and yet provide the larger context in which they can function effectively. Prospects and challenges for understanding values and their role in action, including theoretical and methodological issues, are considered.

Cultural diversity and wisdom of crowds are mutually beneficial and evolutionarily stable

The ability to learn from others (social learning) is often deemed a cause of human species success. But if social learning is indeed more efficient (whether less costly or more accurate) than individual learning, it raises the question of why would anyone engage in individual information seeking, which is a necessary condition for social learning's efficacy. We propose an evolutionary model solving this paradox, provided agents (i) aim not only at information quality but also vie for audience and prestige, and (ii) do not only value accuracy but also reward originality-allowing them to alleviate herding effects. We find that under some conditions (large enough success rate of informed agents and intermediate taste for popularity), both social learning's higher accuracy and the taste for original opinions are evolutionarily-stable, within a mutually beneficial division of labour-like equilibrium. When such conditions are not met, the system most often converges towards mutually detrimental equilibria.

Learning from multiple informants: Children's response to epistemic bases for consensus judgments

Consensus has both social and epistemic value. Children conform to consensus judgments in ways that suggest they are sensitive to the social value of consensus. Here we report two experiments providing evidence that 4-year-old children also are sensitive to the epistemic value of consensus. When multiple informants gave the same judgment concerning the hidden contents of a container, based on the observation of one of their members, children's own judgments tended to align with the consensus judgment over the judgment of a lone character, whose observation received no endorsements. This tendency was reduced, however, when children were shown that the group consensus lacked epistemic warrant. Together, the findings provide evidence that young children are sensitive to the epistemic basis of consensus reports.

Obstacles to the spread of unintuitive beliefs

Many socially significant beliefs are unintuitive, from the harmlessness of GMOs to the efficacy of vaccination, and they are acquired via deference toward individuals who are more confident, more competent or a majority. In the two-step flow model of communication, a first group of individuals acquires some beliefs through deference and then spreads these beliefs more broadly. Ideally, these individuals should be able to explain why they deferred to a given source - to provide arguments from expertise - and others should find these arguments convincing. We test these requirements using a perceptual task with participants from the US and Japan. In Experiment 1, participants were provided with first-hand evidence that they should defer to an expert, leading a majority of participants to adopt the expert's answer. However, when attempting to pass on this answer, only a minority of those participants used arguments from expertise. In Experiment 2, participants receive an argument from expertise describing the expert's competence, instead of witnessing it first-hand. This leads to a significant drop in deference compared with Experiment 1. These experiments highlight significant obstacles to the transmission of unintuitive beliefs.