Dan M. Kahan’s research while affiliated with Yale University and other places

This article examines the science-of-science-communication measurement problem. In its simplest form, the problem reflects the use of externally invalid measures of the dynamics that generate cultural conflict over risk and other policy-relevant facts. But at a more fundamental level, the science-of-science-communication measurement problem inheres in the phenomena being measured themselves. The “beliefs” individuals form about a societal risk such as climate change are not of a piece; rather they reflect the distinct clusters of inferences that individuals draw as they engage information for two distinct ends: to gain access to the collective knowledge furnished by science and to enjoy the sense of identity enabled by membership in a community defined by particular cultural commitments. The article shows how appropriately designed “science comprehension” tests—one general and one specific to climate change—can be used to measure individuals’ reasoning proficiency as collective-knowledge acquirers independently of their reasoning proficiency as cultural-identity protectors. Doing so reveals that there is in fact little disagreement among culturally diverse citizens on what science knows about climate change. The source of the climate-change controversy and like disputes over societal risks is the contamination of the science-communication environment with forms of cultural status competition that make it impossible for diverse citizens to express their reason as both collective-knowledge acquirers and cultural-identity protectors at the same time.

This essay seeks to explain what the "science of science communication" is by doing it. Surveying studies of cultural cognition and related dynamics, it demonstrates how the form of disciplined observation, measurement, and inference distinctive of scientific inquiry can be used to test rival hypotheses on the nature of persistent public conflict over societal risks; indeed, it argues that satisfactory insight into this phenomenon can be achieved only by these means, as opposed to the ad hoc story-telling dominant in popular and even some forms of scholarly discourse. Synthesizing the evidence, the essay proposes that conflict over what is known by science arises from the very conditions of individual freedom and cultural pluralism that make liberal democratic societies distinctively congenial to science. This tension, however, is not an "inherent contradiction"; it is a problem to be solved - by the science of science communication understood as a "new political science" for perfecting enlightened self-government.

This paper describes the “Ordinary Science Intelligence” scale (OSI_2.0). Designed for use in the empirical study of public risk perceptions and science communication, OSI_2.0 comprises items intended to measure a latent (unobserved) capacity to recognize and make use of valid scientific evidence in everyday decisionmaking. The derivation of the items, the relationship of them to the knowledge and skills OSI requires, and the psychometric properties of the scale are examined. Evidence of the external validity of OSI_2.0 is also presented. Finally, the utility of OSI_2.0 is briefly illustrated by using it to assess the relationship of standard survey items on evolution and global warming to science comprehension.

This Report presents empirical evidence relevant to assessing the claim — reported widely in the media and other sources — that the public is growing increasingly anxious about the safety of childhood vaccinations. Based on survey and experimental methods (N = 2,316), the Report presents two principal findings: first, that vaccine risks are neither a matter of concern for the vast majority of the public nor an issue of contention among recognizable demographic, political, or cultural subgroups; and second, that ad hoc forms of risk communication that assert there is mounting resistance to childhood immunizations themselves pose a risk of creating misimpressions and arousing sensibilities that could culturally polarize the public and diminish motivation to cooperate with universal vaccination programs. Based on these findings the Report recommends that government agencies, public health professionals, and other constituents of the public health establishment (1) promote the use of valid and appropriately focused empirical methods for investigating vaccine-risk perceptions and formulating responsive risk communication strategies; (2) discourage ad hoc risk communication based on impressionistic or psychometrically invalid alternatives to these methods; (3) publicize the persistently high rates of childhood vaccination and high levels of public support for universal immunization in the U.S.; and (4) correct ad hoc communicators who misrepresent U.S. vaccination coverage and its relationship to the incidence of childhood diseases.

Neglecting the science of science communication puts the value of decision-relevant science at risk.

The resistance of law enforcers sometimes confounds the efforts of law makers to change social norms. Thus, as legislators expand liability for date rape, domestic violence, and drunk driving, police become less likely to arrest, prosecutors to charge, jurors to convict, and judges to sentence severely. The conspicuous resistance of these decisionmakers in turn reinforces the norms that law makers intended to change. Can this ?sticky norms? pathology be effectively treated? It can be, this article argues, if law makers apply ?gentle nudges? rather than ?hard shoves.? When the law embodies a relatively mild degree of condemnation, the desire of most decisionmakers to discharge their civic duties will override their reluctance to enforce a law that attacks a widespread social norm. The willingness of most decisionmakers to enforce can initiate a self-reinforcing wave of condemnation, thereby allowing lawmakers to increase the severity of the law in the future without prompting resistance from most decisionmakers. The article presents a formal model of this strategy for norm reform, illustrates it with real world examples, and identifies its normative and prescriptive implications.

Decision scientists have identified various plausible sources of ideological polarization over climate change, gun violence, national security, and like issues that turn on empirical evidence. This paper describes a study of three of them: the predominance of heuristic-driven information processing by members of the public; ideologically motivated reasoning; and the cognitive-style correlates of political conservativism. The study generated both observational and experimental data inconsistent with the hypothesis that political conservatism is distinctively associated with either un-reflective thinking or motivated reasoning. Conservatives did no better or worse than liberals on the Cognitive Reflection Test (Frederick, 2005), an objective measure of information-processing dispositions associated with cognitive biases. In addition, the study found that ideologically motivated reasoning is not a consequence of over-reliance on heuristic or intuitive forms of reasoning generally. On the contrary, subjects who scored highest in cognitive reflection were the most likely to display ideologically motivated cognition. These findings corroborated an alternative hypothesis, which identifies ideologically motivated cognition as a form of information processing that promotes individuals' interests in forming and maintaining beliefs that signify their loyalty to important affinity groups. The paper discusses the practical significance of these findings, including the need to develop science communication strategies that shield policy-relevant facts from the influences that turn them into divisive symbols of political identity.

Promoting public comprehension of science is only one aim of the science of science communication and is likely not the most important one for the well-being of a democratic society. Ordinary citizens form quadrillions of correct beliefs on matters that turn on complicated scientific principles they cannot even identify much less understand. The reason they fail to converge on beliefs consistent with scientific evidence on certain other consequential matters—from climate change to genetically modified foods to compusory adolescent HPV vaccination—is not the failure of scientists or science communicators to speak clearly or the inability of ordinary citizens to understand what they are saying. Rather, the source of such conflict is the proliferation of antagonistic cultural meanings. When such associations become attached to particular facts that admit of scientific investigation, these meanings are a kind of pollution of the science communication environment that disables the faculties ordinary citizens use to reliably absorb collective knowledge from their everyday interactions. The quality of the science communication environment is thus just as critical for enlightened self-government as the quality of the natural environment is for the physical health and well-being of a society’s members. Understanding how this science communication environment works, fashioning procedures to prevent it from becoming contaminated with antagonistic meanings, and formulating effective interventions to detoxify it when protective strategies fail—those are the most critical functions science communication can perform in a democratic society.