The Influence of Uncertain Map Features on Risk Beliefs and Perceived Ambiguity for Maps of Modeled Cancer Risk from Air Pollution

Maps are often used to convey information generated by models, for example, modeled cancer risk from air pollution. The concrete nature of images, such as maps, may convey more certainty than warranted for modeled information. Three map features were selected to communicate the uncertainty of modeled cancer risk: (i) map contours appeared in or out of focus, (ii) one or three colors were used, and (iii) a verbal‐relative or numeric risk expression was used in the legend. Study aims were to assess how these features influenced risk beliefs and the ambiguity of risk beliefs at four assigned map locations that varied by risk level. We applied an integrated conceptual framework to conduct this full factorial experiment with 32 maps that varied by the three dichotomous features and four risk levels; 826 university students participated. Data was analyzed using structural equation modeling. Unfocused contours and the verbal‐relative risk expression generated more ambiguity than their counterparts. Focused contours generated stronger risk beliefs for higher risk levels and weaker beliefs for lower risk levels. Number of colors had minimal influence. The magnitude of risk level, conveyed using incrementally darker shading, had a substantial dose‐response influence on the strength of risk beliefs. Personal characteristics of prior beliefs and numeracy also had substantial influences. Bottom‐up and top‐down information processing suggest why iconic visual features of incremental shading and contour focus had the strongest visual influences on risk beliefs and ambiguity. Variations in contour focus and risk expression show promise for fostering appropriate levels of ambiguity.     

The Distinction Between Risk and Hazard: Understanding and Use in Stakeholder Communication

A major issue in all risk communication efforts is the distinction between the terms “risk” and “hazard.” The potential to harm a target such as human health or the environment is normally defined as a hazard, whereas risk also encompasses the probability of exposure and the extent of damage. What can be observed again and again in risk communication processes are misunderstandings and communication gaps related to these crucial terms. We asked a sample of 53 experts from public authorities, business and industry, and environmental and consumer organizations in Germany to outline their understanding and use of these terms using both the methods of expert interviews and focus groups. The empirical study made clear that the terms risk and hazard are perceived and used very differently in risk communication depending on the perspective of the stakeholders. Several factors can be identified, such as responsibility for hazard avoidance, economic interest, or a watchdog role. Thus, communication gaps can be reduced to a four‐fold problem matrix comprising a semantic, conceptual, strategic, and control problem. The empirical study made clear that risks and hazards are perceived very differently depending on the stakeholders’ perspective. Their own worldviews played a major role in their specific use of the two terms hazards and risks in communication.     

The Role of Emotions in Risk Communication

We present two experiments investigating the role of emotions concerning technological and natural hazards. In the first experiment, technological hazards aroused stronger emotions, and were considered to be riskier than natural hazards. No differences were found between the texts versus audio presentations. However, the presence of pictures aroused stronger emotions and increased the perceived risk. Emotions play a mediating role between hazard types and perceived risk, as well as between pictures and perceived risk. The second experiment adopted real‐world materials from webpages and TV. Emotions again play a mediating role between pictorial information and risk perception. Moreover, specific emotions were found to be associated with different types of action tendencies. For example, loss‐based emotions (e.g., fear, regret) tend to lead to prevention strategies, whereas ethical emotions (e.g., anger) lead to aggressive behavior. We also find that loss‐based emotions in the technical hazard scenario trigger more coping strategies (from prevention to retaliation) than in the natural hazard scenario.     

The Use of Mental Models in Chemical Risk Protection: Developing a Generic Workplace Methodology

We adopted a comparative approach to evaluate and extend a generic methodology to analyze the different sets of beliefs held about chemical hazards in the workplace. Our study mapped existing knowledge structures about the risks associated with the use of perchloroethylene and rosin-based solder flux in differing workplaces. "Influence diagrams" were used to represent beliefs held by chemical experts; "user models" were developed from data elicited from open-ended interviews with the workplace users of the chemicals. The juxtaposition of expert and user understandings of chemical risks enabled us to identify knowledge gaps and misunderstandings and to reinforce appropriate sets of safety beliefs and behavior relevant to chemical risk communications. By designing safety information to be more relevant to the workplace context of users, we believe that employers and employees may gain improved knowledge about chemical hazards in the workplace, such that better chemical risk management, self-protection, and informed decision making develop over time.     

Varying Risk Comparison Elements: Effects on Public Reactions

Expanding a limited empirical base on effects of risk comparisons, a pilot experiment explored how varying elements of such comparisons might influence public response. The scenario used was a hypothetical trial of an asbestos-installing firm for putting students and staff at a junior high school at "unreasonable risk," first used by Slovic et al. (1990). Study participants played the role of jurors in the trial, asked to rate the risk, the firm's guilt, whether it should be made liable for future health effects, whether the school should be occupied in its current condition, and whether the asbestos should be removed at a cost of 3 million dollars. Opportunity samples of New Jersey residents (n= 309) received information intended to vary four comparison attributes: number of dimensions of comparison; single versus multiple ways of expressing mortality; a narrative to explain and justify the risk comparison; and the hypothetical role of the participant (juror vs. parent). The dependent variable was a hazard scale constructed from four of the five postcomparison judgments. ANOVA found format variations swamped in their effect by concern about asbestos, with the absence of a narrative and the parental role being the only attributes that increased negative risk reactions. Multiple regression analyses found that multidimensionality, narrative, role, and the presence of any risk comparison at all had significant effects when these (plus death formats) were the only independent variables. However, only multidimensionality (which increased negative reactions) retained significance when asbestos concern, risk beliefs (no safe level of exposure to a carcinogen; any exposure leads to cancer), and demographic variables were added to the analysis. Concern and risk beliefs alone explained 33% of variance in hazard scores; adding demographics and risk comparison variables only raised explained variance to 36% (having children at home and being exposed to multidimensional risk comparisons raised scores; age and income lowered them). The results underline the potentially small effect of risk comparison information on risk views (at least between subjects), but offer some insight into aspects of message design left unexplored in empirical literature to date.     

Correlates of Household Seismic Hazard Adjustment Adoption

This study examined the relationships of self-reported adoption of 12 seismic hazard adjustments (pre-impact actions to reduce danger to persons and property) with respondents' demographic characteristics, perceived risk, perceived hazard knowledge, perceived protection responsibility, and perceived attributes of the hazard adjustments. Consistent with theoretical predictions, perceived attributes of the hazard adjustments differentiated among the adjustments and had stronger correlations with adoption than any of the other predictors. These results identify the adjustments and attributes that emergency managers should address to have the greatest impact on improving household adjustment to earthquake hazard.     

Perception of Hazards: The Role of Social Trust and Knowledge

Recent research indicates that social trust of those who manage a hazard is strongly correlated to judgments about the hazard's risk and benefits. The present study investigates the more specific question of “For which hazards is this?” It was postulated that when an individual lacks knowledge about a hazard, social trust of authorities managing the hazard determines perceived risks and benefits. On the other hand, when an individual has personal knowledge about a hazard and therefore does not need to rely on managing authorities, social trust is unrelated to judged risks and benefits. Participants (N = 91) assessed risks, benefits, and trust in managing authorities and personal knowledge associated with 25 hazardous technologies and activities. As expected, strong correlations between social trust and judged risks and benefits were observed for hazards about which people did not possess much knowledge. No significant correlations between social trust and judged risks and benefits were found for hazards about which people were knowledgeable. Results suggest that the lay public relies on social trust when making judgments of risks and benefits when personal knowledge about a hazard is lacking. Replicating findings of other studies, the present study also found negative correlations between perceived risks and perceived benefits. When social trust was controlled for, correlations between perceived risks and benefits diminished. Implications of the results for risk management are discussed.     

Evidence maps: communicating risk assessments in societal controversies: the case of engineered nanoparticles

The transparent and fair characterization of scientific evidence for reporting the results of a hazard assessment is a demanding task. In this article, we present an approach for characterizing evidence--the evidence map approach. The theoretical starting point is to view evidence characterization as a form of argumentation. Thus, evidence maps are designed to depict the evidence base, the pro and con arguments, and the remaining uncertainties, which together lead experts to their conclusions when summarizing and evaluating the scientific evidence about a potential hazard. To illustrate its use, the evidence maps approach is applied to characterizing the health-relevant effects of engineered nanoparticles. Empirical data from an online survey suggests that the use of evidence maps improves the reporting of hazard assessments. Nonexperts prefer to receive the information included in an evidence map in order to come to an informed judgment. Furthermore, the benefits and limitations of evidence maps are discussed in the light of recent literature on risk communication. Finally, the article underlines the need for further research in order to increase quality of evidence reporting.     

Determinants and Mapping of Collective Perceptions of Technological Risk: The Case of the Second Nuclear Power Plant in Taiwan

Nuclear power is a highly controversial and salient example of environmental risk. The siting or operating of a nuclear power plant often faces widespread public opposition. Although studies of public perceptions of nuclear power date back to 1970s, little research attempts to explain the spatial heterogeneity of risk attitude toward nuclear power among individuals or communities. This article intends to improve the knowledge about the major factors contributing to nuclear power plant risk perceptions by mapping the geographical patterns of local risk perception and examining the determinants in forming the nature and distribution of the perceived risk among potentially affected population. The analysis was conducted by a case study of the Second Nuclear Power Plant (SNPP) in Taiwan by using a novel methodology that incorporates a comprehensive risk perception (CRP) model into an ethnographic approach called risk perception mapping (RPM). First, we examined the determinants of local nuclear power risk perceptions through the CRP model and multivariate regression analysis. Second, the results were integrated with the RPM approach to map and explain the spatial pattern of risk perceptions. The findings demonstrate that the respondents regard the nuclear power plant as an extremely high‐risk facility, causing them to oppose the SNPP and reject the compensation payment to accept its continuing operation. Results also indicate that perceptions of nuclear power risk were mainly influenced by social trust, psychological and socioeconomic attributes, proximity, and the perceived effects of the SNPP on the quality of everyday life.     

The Roles of Group Membership, Beliefs, and Norms in Ecological Risk Perception

Variability in ecological risk perceptions was investigated by surveying members of four stakeholder groups commonly involved in environmental policy debates. Fifty-six individuals from government, industry, environmental, and general-public groups completed a risk-perception survey in which they evaluated 34 environmental hazards on 17 attributes and also evaluated the riskiness and acceptability of each hazard. In addition, participants reported their environmental beliefs and norms using Dunlap et al.'s revised New Ecological Paradigm Scale and modified versions of Schwartz's Awareness of Consequences and Personal Norms Scales. Group membership was predictive of participants' scores on the belief and norm scales. Factor analysis of attribute ratings (averaged across participants) revealed the anticipated three oblique factors: ecological impacts, scientific understanding, and aesthetic impacts. Factor patterns were very similar for the four stakeholder groups. Factors from the aggregate analysis were predictive of individuals' riskiness judgments, but these relationships were moderated by participants' group membership, beliefs, and norms. Compared to members of other groups, members of the general public placed less emphasis on ecological impacts and more emphasis on the other two factors when judging the ecological riskiness of hazards. To our knowledge, these results represent the first formal tests of interactions between hazard characteristics and participant characteristics in determining riskiness judgments, and illustrate how traditional psychometric analyses can be successfully coupled with individual-difference measures to improve the understanding of risk perception.     

Some Criteria for Evaluating Risk Messages

Seven criteria are presented for use in evaluating communications designed to explain the magnitude of a risk. The criteria are: (1) comprehension (Does the audience understand the content of the communication?); (2) agreement (Does the audience agree with the recommendation or interpretation contained in the message?); (3) dose-response consistency (Do people facing a higher dose of a hazard perceive the risk as greater and/or show a greater readiness to take action than people exposed to a lower dose of this hazard?); (4) hazard-response consistency (Do people facing a hazard that is higher in risk perceive the risk as greater and/or show a greater readiness to take action than people exposed to a hazard that is lower in risk?); (5) uniformity (Do audience members exposed to the same level of risk tend to have the same responses to this risk?); (6) audience evaluation (Does the audience judge the message to have been helpful, accurate, clear, etc.?); and (7) types of communication failures (When different types of failures are possible, are the failures that occur generally of the more acceptable variety?). Each of these criteria is illustrated with data collected in a test of message formats designed to explain the risk presented by radon gas in a home.     

Hazard Experience,Geophysical Vulnerability,and Flood Risk Perceptions in a Postdisaster City,the Case of New Orleans

This article investigates the determinants of flood risk perceptions in New Orleans, Louisiana (United States), a deltaic coastal city highly vulnerable to seasonal nuisance flooding and hurricane‐induced deluges and storm surges. Few studies have investigated the influence of hazard experience, geophysical vulnerability (hazard proximity), and risk perceptions in cities undergoing postdisaster recovery and rebuilding. We use ordinal logistic regression techniques to analyze experiential, geophysical, and sociodemographic variables derived from a survey of 384 residents in seven neighborhoods. We find that residents living in neighborhoods that flooded during Hurricane Katrina exhibit higher levels of perceived risk than those residents living in neighborhoods that did not flood. In addition, findings suggest that flood risk perception is positively associated with female gender, lower income, and direct flood experiences. In conclusion, we discuss the implications of these findings for theoretical and empirical research on environmental risk, flood risk communication strategies, and flood hazards planning.     

Methodological Approaches to Assessing Risk Perceptions Associated with Food-Related Hazards

The psychometric approach developed by Slovic and his co-workers has been effectively used to assess risk perceptions associated with different food-related hazards. However, further examination (using questionnaire data and partial correlation techniques) has indicated that technological hazards are highly differentiated from lifestyle hazards, in terms of both hazard control and knowledge about the hazard. Optimistic bias was also seen to vary between hazards. Further research has focused on a particular hazard, genetic engineering. Risk perceptions associated with genetic engineering are underpinned by ethical concern and questions relating to perceived need for the technology, as well as perceptions of risk or harm. However, increasing the specificity of hazard stimuli was found to alter the factor structure of underlying risk perceptions. The utility of preference mapping procedures in determining individual differences in trust in risk regulators is also discussed.     

Taxonomic Analysis of Perceived Risk: Modeling Individual and Group Perceptions Within Homogeneous Hazard Domains

Previous studies of risk perception have typically focused on the mean judgments of a group of people regarding the riskiness (or safety) of a diverse set of hazardous activities, substances, and technologies. This paper reports the results of two studies that take a different path. Study 1 investigated whether models within a single technological domain were similar to previous models based on group means and diverse hazards. Study 2 created a group taxonomy of perceived risk for only one technological domain, railroads, and examined whether the structure of that taxonomy corresponded with taxonomies derived from prior studies of diverse hazards. Results from Study 1 indicated that the importance of various risk characteristics in determining perceived risk differed across individuals and across hazards, but not so much as to invalidate the results of earlier studies based on group means and diverse hazards. In Study 2, the detailed analysis of railroad hazards produced a structure that had both important similarities to, and dissimilarities from, the structure obtained in prior research with diverse hazard domains. The data also indicated that railroad hazards are really quite diverse, with some approaching nuclear reactors in their perceived seriousness. These results suggest that information about the diversity of perceptions within a single domain of hazards could provide valuable input to risk-management decisions.     

Human and Nature‐Caused Hazards: The Affect Heuristic Causes Biased Decisions

People are more concerned about the negative consequences of human hazards compared with natural hazards. Results of four experiments show that the same negative outcome (e.g., number of birds killed by an oil spill) was more negatively evaluated when caused by humans than when caused by nature. Results further show that when identical risk information was provided, participants evaluated nuclear power more negatively compared with solar power. The affect associated with the hazard per se influenced the interpretation of the new information. Furthermore, the affect experienced in the situation fully mediated the evaluation of the negative outcomes of a hazard. People's reliance on the affect heuristic is a challenge for acceptance of cost‐benefit analyses because equally negative outcomes are differently evaluated depending on the cause. Symbolically significant information and the affect evoked by this information may result in biased and riskier decisions.     

Efficacy,Action, and Support for Reducing Climate Change Risks

A growing body of research demonstrates that believing action to reduce the risks of climate change is both possible (self‐efficacy) and effective (response efficacy) is essential to motivate and sustain risk mitigation efforts. Despite this potentially critical role of efficacy beliefs, measures and their use vary wildly in climate change risk perception and communication research, making it hard to compare and learn from efficacy studies. To address this problem and advance our understanding of efficacy beliefs, this article makes three contributions. First, we present a theoretically motivated approach to measuring climate change mitigation efficacy, in light of diverse proposed, perceived, and previously researched strategies. Second, we test this in two national survey samples (Amazon's Mechanical Turk N = 405, GfK Knowledge Panel N = 1,820), demonstrating largely coherent beliefs by level of action and discrimination between types of efficacy. Four additive efficacy scales emerge: personal self‐efficacy, personal response efficacy, government and collective self‐efficacy, and government and collective response efficacy. Third, we employ the resulting efficacy scales in mediation models to test how well efficacy beliefs predict climate change policy support, controlling for specific knowledge, risk perceptions, and ideology, and allowing for mediation by concern. Concern fully mediates the relatively strong effects of perceived risk on policy support, but only partly mediates efficacy beliefs. Stronger government and collective response efficacy beliefs and personal self‐efficacy beliefs are both directly and indirectly associated with greater support for reducing the risks of climate change, even after controlling for ideology and causal beliefs about climate change.     

Does Communicating (Flood) Risk Affect (Flood) Risk Perceptions? Results of a Quasi‐Experimental Study

People's risk perceptions are generally regarded as an important determinant of their decisions to adjust to natural hazards. However, few studies have evaluated how risk communication programs affect these risk perceptions. This study evaluates the effects of a small-scale flood risk communication program in the Netherlands, consisting of workshops and focus group discussions. The effects on the workshop participants' ( n  = 24) and focus group participants' ( n  = 16) flood risk perceptions were evaluated in a pretest-posttest control group ( n  = 40) design that focused on two mechanisms of attitude change—direct personal experience and attitude polarization. We expected that (H1) workshop participants would show greater shifts in their flood risk perceptions compared with control group participants and that (H2) focus groups would rather produce the conditions for attitude polarization (shifts toward more extreme attitudinal positions after group discussion). However, the results provide only modest support for these hypotheses, perhaps because of a mismatch between the sessions' contents and the risk perception measures. An important contribution of this study is that it examined risk perception data by both conventional tests of the mean differences and tests for attitude polarization. Moreover, the possibility that attitude polarization could cause people to confirm their preexisting (hazard) beliefs could have important implications for risk communication.     

Risk Perception,Experience, and Objective Risk: A Cross‐National Study with European Emergency Survivors

Understanding public risk perceptions and their underlying processes is important in order to learn more about the way people interpret and respond to hazardous emergency events. Direct experience with an involuntary hazard has been found to heighten the perceived risk of experiencing the same hazard and its consequences in the future, but it remains unclear if cross‐over effects are possible (i.e., experience with one hazard influencing perceived risk for other hazards also). Furthermore, the impact of objective risk and country of residence on perceived risk is not well understood. As part of the BeSeCu (Behavior, Security, and Culture) Project, a sample of 1,045 survivors of emergencies from seven European countries (i.e., Germany, the Czech Republic, Poland, Sweden, Spain, Turkey, and Italy) was drawn. Results revealed heightened perceived risk for emergency events (i.e., domestic and public fires, earthquakes, floods, and terrorist attacks) when the event had been experienced previously plus some evidence of cross‐over effects, although these effects were not so strong. The largest country differences in perceived risk were observed for earthquakes, but this effect was significantly reduced by taking into account the objective earthquake risk. For fires, floods, terrorist attacks, and traffic accidents, only small country differences in perceived risk were found. Further studies including a larger number of countries are welcomed.     

Do People Believe Combined Hazards Can Present Synergistic Risks?

The risk attributable to some hazard combinations can be greater than the sum of the risk attributable to each constituent hazard. Such "synergistic risks" occur in several domains, can vary in magnitude, and often have harmful, even life-threatening, outcomes. Yet, the extent to which people believe that combined hazards can present synergistic risks is unclear. We present the results of two experimental studies aimed at addressing this issue. In both studies, participants examined synergistic and additive risk scenarios, and judged whether these were possible. The results indicate that the proportion of people who believe that synergistic risks can occur declines linearly as the magnitude of the synergistic risk increases. We also find that people believe, despite scientific evidence to the contrary, that certain hazard combinations are more likely to present additive or weakly synergistic risks than synergistic risks of higher magnitudes. Furthermore, our findings did not vary as a simple function of hazard domain (health vs. social), but varied according to the characteristics of the specific hazards considered (specified vs. unspecified drug combinations). These results suggest that many people's beliefs concerning the risk attributable to combined hazards could lead them to underestimate the threat posed by combinations that present synergistic risks, particularly for hazard combinations that present higher synergistic risk magnitudes. These findings highlight a need to develop risk communications that can effectively increase awareness of synergistic risks.     

Influence of Risk Perception on Attitudes and Norms Regarding Electronic Cigarettes

The use of electronic cigarettes has grown substantially over the last few years. Currently, about 4% of adults use electronic cigarettes, about 16% of high school students report use in the past 30 days, as do approximately 11–25% of college students. A hallmark of the reduction in tobacco use has been the shift in social norms concerning smoking in public. Such norms may also drive views on acceptability of public electronic cigarette use. While normative factors have been given attention, little substantive application of the literature on risk perception has been brought to bear. The overall aim of this study was to place a cognitive–affective measure of risk perception within a model that also includes social cues for e‐cigarettes, addictiveness beliefs, and tobacco use to predict perceived social acceptability for public use of e‐cigarettes. To do so, a cross‐sectional study using an online survey was conducted among a sample of undergraduate students at a Western university (n = 395). A structural equation model showed that the acceptability of public e‐cigarette use was influenced by social cues, beliefs about addiction, and cognitive risk perception, even after controlling for nicotine use. What is revealed is that cognitive assessment of e‐cigarette risk and perception of addictiveness had a suppressing effect on perceived acceptability of public vaping, while greater exposure to social cues exerted a countervailing effect. This is evidence of the role that risk perception and social norms may play in the increases in electronic cigarette use that have been observed.