Belief Polarization Research Articles

How rational inference about authority debunking can curtail, sustain, or spread belief polarization.

In polarized societies, divided subgroups of people have different perspectives on a range of topics. Aiming to reduce polarization, authorities may use debunking to lend support to one perspective over another. Debunking by authorities gives all observers shared information, which could reduce disagreement. In practice, however, debunking may have no effect or could even contribute to further polarization of beliefs. We developed a cognitively inspired model of observers' rational inferences from an authority's debunking. After observing each debunking attempt, simulated observers simultaneously update their beliefs about the perspective underlying the debunked claims and about the authority's motives, using an intuitive causal model of the authority's decision-making process. We varied the observers' prior beliefs and uncertainty systematically. Simulations generated a range of outcomes, from belief convergence (less common) to persistent divergence (more common). In many simulations, observers who initially held shared beliefs about the authority later acquired polarized beliefs about the authority's biases and commitment to truth. These polarized beliefs constrained the authority's influence on new topics, making it possible for belief polarization to spread. We discuss the implications of the model with respect to beliefs about elections.

The truth or your truth: polarization in Arctic climate change on X (Twitter)

ABSTRACT Political polarization is increasingly undermining citizen trust. As authorities and science lose legitimacy due to the intensification of polarization, the barriers to finding policy solutions, particularly on divisive issues like climate change, become more daunting. Exacerbating this problem, by drawing on diverse sources of validation, including scientific findings and traditional and social media, opposing sides construct their own ‘truth,’ often fueled by misinformation and misperceptions. This phenomenon, known as factual belief polarization, is exacerbated by selective exposure within echo chambers on social media, where individuals are insulated from alternative perspectives. This paper examines polarization in public debate on climate change in the Arctic, focusing on the role of social media via X (Twitter). Through an analysis of top retweets between the period of May 2021 to April 2022, key themes related to climate change are identified and the degree of polarization assessed. In combination with an overview of the content of the tweets, the paper elucidates whether polarization is similar to general debates over climate change and what type of argumentation is made by both climate change advocates and deniers.

Factual belief polarization between Democrats and Republicans: source or epiphenomenon of ideological and affective polarization?

Democrats and Republicans have polarized in their attitudes (i.e., ideological polarization) and their feelings toward each other (i.e., affective polarization). Simultaneously, both groups also seem to diverge in their factual beliefs about reality. This preregistered survey experiment among 2,253 American citizens examined how this factual belief polarization may or may not fuel ideological and affective polarization around four key issues: income differences, immigration, climate change, and defense spending. On all issues except immigration, Democrats and Republicans were equally or more divided in their factual beliefs about the present than in their ideals for the future. Corrective information decreased partisan polarization over some ideals, but not directional policy attitudes. Priming respondents' factual beliefs conversely increased polarization around defense spending, but not other issues. Much remains unclear about the complex relation between factual beliefs and polarization, but measuring ideals and priming beliefs could be promising avenues for future research.

Tracking politically motivated reasoning in the brain: the role of mentalizing, value-encoding, and error-detection networks.

Susceptibility to misinformation and belief polarization often reflect people's tendency to incorporate information in a biased way. Despite the presence of competing theoretical models, the underlying neurocognitive mechanisms of motivated reasoning remain elusive as previous empirical work did not properly track the belief formation process. To address this problem, we employed a design that identifies motivated reasoning as directional deviations from a Bayesian benchmark of unbiased belief updating. We asked members of a pro-immigration or an anti-immigration group how much they endorse factual messages on foreign criminality, a polarizing political topic. Both groups exhibited a desirability bias by over-endorsing attitude-consistent messages and under-endorsing attitude-discrepant messages and an identity bias by over-endorsing messages from ingroup members and under-endorsing messages from outgroup members. In both groups, neural responses to the messages predicted subsequent expression of desirability and identity biases suggesting a common neural basis of motivated reasoning across ideologically opposing groups. Specifically, brain regions implicated in encoding value, error detection, and mentalizing tracked the degree of desirability bias. Less extensive activation in the mentalizing network tracked the degree of identity bias. These findings illustrate the distinct neurocognitive architecture of desirability and identity biases and inform existing cognitive models of politically motivated reasoning.

Calculated Comparisons: Manufacturing Societal Causal Judgments by Implying Different Counterfactual Outcomes.

How do people come to opposite causal judgments about societal problems, such as whether a public health policy reduced COVID-19 cases? The current research tests an understudied cognitive mechanism in which people may agree about what actually happened (e.g., that a public health policy was implemented and COVID-19 cases declined), but can be made to disagree about the counterfactual, or what would have happened otherwise (e.g., whether COVID-19 cases would have declined naturally without intervention) via comparison cases. Across two preregistered studies (total N = 480), participants reasoned about the implementation of a public policy that was followed by an immediate decline in novel virus cases. Study 1 shows that people's judgments about the causal impact of the policy could be pushed in opposite directions by emphasizing comparison cases that imply different counterfactual outcomes. Study 2 finds that people recognize they can use such information to influence others. Specifically, in service of persuading others to support or reject a public health policy, people systematically showed comparison cases implying the counterfactual outcome that aligned with their position. These findings were robust across samples of U.S. college students and politically and socioeconomically diverse U.S. adults. Together, these studies suggest that implied counterfactuals are a powerful tool that individuals can use to manufacture others' causal judgments and warrant further investigation as a mechanism contributing to belief polarization.

Interthematic Polarization

Abstract In recent epistemology, belief polarization is generally defined as a process by which a disagreement on a single proposition becomes more extreme over time. Outside of the philosophical literature, however, “polarization” is often used for a different epistemic phenomenon, namely the process by which people's beliefs on unrelated topics become increasingly correlated over time. This paper argues that the latter type of polarization, here labeled interthematic polarization, is often rational from each individual's point of view. This suggests that belief polarization is not necessarily a failure of individual rationality, but instead a failure of the social structures within which we live our epistemic lives.

Online Interaction Turns the Congeniality Bias Into an Uncongeniality Bias.

Online phenomena like echo chambers and polarization are believed to be driven by humans' penchant to selectively expose themselves to attitudinally congenial content. However, if like-minded content were the only predictor of online behavior, heated debate and flaming on the Internet would hardly occur. Research has overlooked how online behavior changes when people are given an opportunity to reply to dissenters. Three experiments (total N = 320; convenience student samples from Germany) and an internal meta-analysis show that in a discussion-forum setting where participants can reply to earlier comments larger cognitive conflict between participant attitude and comment attitude predicts higher likelihood to respond (uncongeniality bias). When the discussion climate was friendly (vs. oppositional) to the views of participants, the uncongeniality bias was more pronounced and was also associated with attitude polarization. These results suggest that belief polarization on social media may not only be driven by congeniality but also by conflict.

Factors influencing the update of beliefs regarding controversial political issues

ABSTRACT Selectively integrating new information contributes to belief polarization and compromises public discourse. To better understand factors that underlie biased belief updating, I conducted three pre-registered studies covering different controversial political issues. The main hypothesis was that cognitively devaluing new information hinders belief updating. Support for this hypothesis was found in only one of the three issues. The only factor that consistently influenced belief updating across issues was the discrepancy between prior beliefs and new information. These results suggest that usually people do use evidence to correct their beliefs, but may refuse to do so if doubts about its generalizability arise.

Moralization and extremism robustly amplify myside sharing.

We explored whether moralization and attitude extremity may amplify a preference to share politically congruent ("myside") partisan news and what types of targeted interventions may reduce this tendency. Across 12 online experiments (N = 6,989), we examined decisions to share news touching on the divisive issues of gun control, abortion, gender and racial equality, and immigration. Myside sharing was systematically observed and was consistently amplified when participants (i) moralized and (ii) were attitudinally extreme on the issue. The amplification of myside sharing by moralization also frequently occurred above and beyond that of attitude extremity. These effects generalized to both true and fake partisan news. We then examined a number of interventions meant to curb myside sharing by manipulating (i) the audience to which people imagined sharing partisan news (political friends vs. foes), (ii) the anonymity of the account used (anonymous vs. personal), (iii) a message warning against the myside bias, and (iv) a message warning against the reputational costs of sharing "mysided" fake news coupled with an interactive rating task. While some of those manipulations slightly decreased sharing in general and/or the size of myside sharing, the amplification of myside sharing by moral attitudes was consistently robust to these interventions. Our findings regarding the robust exaggeration of selective communication by morality and extremism offer important insights into belief polarization and the spread of partisan and false information online.

Learning from Shared News: When Abundant Information Leads to Belief Polarization

AbstractWe study learning via shared news. Each period agents receive the same quantity and quality of firsthand information and can share it with friends. Some friends (possibly few) share selectively, generating heterogeneous news diets across agents. Agents are aware of selective sharing and update beliefs by Bayes’s rule. Contrary to standard learning results, we show that beliefs can diverge in this environment, leading to polarization. This requires that (i) agents hold misperceptions (even minor) about friends’ sharing and (ii) information quality is sufficiently low. Polarization can worsen when agents’ friend networks expand. When the quantity of firsthand information becomes large, agents can hold opposite extreme beliefs, resulting in severe polarization. We find that news aggregators can curb polarization caused by news sharing. Our results hold without media bias or fake news, so eliminating these is not sufficient to reduce polarization. When fake news is included, it can lead to polarization but only through misperceived selective sharing. We apply our theory to shed light on the polarization of public opinion about climate change in the United States.

Understanding factual belief polarization: the role of trust, political sophistication, and affective polarization

Political opponents are often divided not only in their attitudes (i.e., ideological polarization) and their feelings toward each other (i.e., affective polarization), but also in their factual perceptions of reality (i.e., factual belief polarization). This paper describes factual belief polarization in the Netherlands around three core issues. Furthermore, this paper examines who are most susceptible to this type of polarization. Analyses on the 2021 Dutch Parliamentary Election Study reveal that citizens hold different perceptions than their political opponents about income inequality, immigration, and climate change. This type of polarization is strongest among citizens who have hostile feelings toward their political opponents and, paradoxically, among those who are highly educated and interested in politics. Trust in epistemic authorities did not mitigate factual belief polarization, perhaps because this trust has itself become politicized. These findings underline that factual belief polarization constitutes a core pillar of political polarization, alongside ideological and affective polarization.

From Belief Polarization to Echo Chambers: A Rationalizing Account

AbstractBelief polarization (BP) is widely seen to threaten havoc on our shared political lives. It is often assumed that BP is the product of epistemically irrational behaviors at the individual level. After distinguishing between BP as it occurs in intra-group and inter-group settings, this paper argues that neither process necessarily reflects individual epistemic irrationality. It is true that these processes can work in tandem to produce so-called “echo chambers.” But while echo chambers are often problematic from the point of view of collective rationality, it doesn't follow that individuals are doing anything wrong, epistemically speaking, in seeking them out. In non-ideal socio-epistemic contexts, echo chamber construction might provide one's best defense against systematic misinformation and deception.

The relationship between visual confirmation bias, belief consistency, and belief polarization

ABSTRACT Video evidence depicting physical altercations has polarized public opinions and courtroom decisions about social issues including race relations and police use-of-force, we believe, in part because of the way people process dynamic visual stimuli across repeated viewing opportunities. We reanalyzed two studies that covertly collected eye-tracking data to quantify and model visual confirmation bias (VCB) – the degree to which eye movements replicate previous patterns of looking across multiple viewing opportunities. We tracked the location of eye gaze when participants (N1 = 320; N2 = 212) watched the same video twice depicting an altercation between an officer and a civilian (Study 1) or a Black and a White actor (Study 2). In pilot tests, we provided evidence regarding the construct validity of statistical measures of concordance tracking similarities in where perceivers directed eye gaze across viewings as an index of VCB. In our pre-registered analytic plan, we used these metrics to probe for relationships with punishment decisions made about targets after the first and second viewings. Contrary to predictions, our pre-registered analyses found no associations between VCB, consistency, and polarization in punishment. We present exploratory analyses probing potential moderators of the association between VCB and these outcome measures. We offer practical suggestions for researchers measuring and modeling eye gaze during the presentation of dynamic stimuli across multiple viewings, particularly in the context of intergroup decision research.

Belief Polarization and COVID-19

Belief Polarization and COVID-19

Belief Polarization, Unconscious Biases, and Financial Markets

Belief Polarization, Unconscious Biases, and Financial Markets

Discourse Uncertainty and Belief Polarization in Financial Markets: Evidence from Equity Analysts

Discourse Uncertainty and Belief Polarization in Financial Markets: Evidence from Equity Analysts

Group-Managed Real Options

Abstract We study a standard real-option problem in which sequential decisions are made through voting by a group of members with heterogeneous beliefs. We show that, when facing both investment and abandonment timing decisions, the group behavior cannot be replicated by that of a representative “median” member. As a result, members’ disagreement generates inertia—the group delays investment relative to a single-agent case—and underinvestment—the group rejects projects that are supported by a majority of members, acting in autarky. These coordination frictions hold in groups of any size, for general voting protocols, and are exacerbated by belief polarization.

Belief polarization in a complex world: A learning theory perspective

We present two models of how people form beliefs that are based on machine learning theory. We illustrate how these models give insight into observed human phenomena by showing how polarized beliefs can arise even when people are exposed to almost identical sources of information. In our first model, people form beliefs that are deterministic functions that best fit their past data (training sets). In that model, their inability to form probabilistic beliefs can lead people to have opposing views even if their data are drawn from distributions that only slightly disagree. In the second model, people pay a cost that is increasing in the complexity of the function that represents their beliefs. In this second model, even with large training sets drawn from exactly the same distribution, agents can disagree substantially because they simplify the world along different dimensions. We discuss what these models of belief formation suggest for improving people's accuracy and agreement.

The Status Quo and Belief Polarization of Inattentive Agents: Theory and Experiment

We show that rational but inattentive agents can become polarized, even in expectation. This is driven by agents’ choice of not only how much information to acquire, but also what type of information. We present how optimal information acquisition, and subsequent belief formation, depends crucially on the agent-specific status quo valuation. Beliefs can systematically update away from the realized truth and even agents with the same initial beliefs might become polarized. We design a laboratory experiment to test the model’s predictions; the results confirm our predictions about the mechanism (rational information acquisition) and its effect on beliefs (systematic polarization). Keywords: polarization, beliefs updating, rational inattention, status quo, experiment. JEL codes: C92, D72, D83, D84, D91

The Distribution of Investor Beliefs, Stock Ownership and Stock Returns

We study theoretically and empirically the relationship between investor beliefs, ownership dispersion and stock returns. We find that high dispersion, measured by high breadth or low Herfindahl index, forecasts returns positively for large stocks, as in Chen, Hong and Stein (2002), but negatively for small stocks. We explain that relationship in a difference-of-opinion model in which stocks differ in the size of investor disagreements and the extent of belief polarization. These differences are characterized by range and kurtosis, respectively. Proxying investor beliefs by analyst forecasts, we find that range and kurtosis affect ownership dispersion in the way that our model predicts. Institutional subscribers to the NBER working paper series, and residents of developing countries may download this paper without additional charge at www.nber.org.