Judged Lethality: How Much People Seem to Know Depends Upon How They Are Asked

Four formally equivalent response modes were used to elicit laypeople's beliefs regarding the lethality of various potential causes of death. Results showed that respondents had an articulated core of beliefs about lethality that yielded similar orderings of maladies by lethality regardless of the response mode used. Moreover, this subjective ordering was fairly similar to that revealed by public health statistics. However, the absolute estimates of lethality produced by the different response modes varied enormously. Depending upon the mode used, respondents were seen to greatly overestimate or greatly underestimate lethality. The implications of these discrepancies for public education and risk analysis are explored.     

A Deliberative Method for Ranking Risks (II): Evaluation of Validity and Agreement among Risk Managers

A deliberative method for ranking risks was evaluated in a study involving 218 risk managers. Both holistic and multiattribute procedures were used to assess individual and group rankings of health and safety risks facing students at a fictitious middle school. Consistency between the rankings that emerged from these two procedures was reasonably high for individuals and for groups, suggesting that these procedures capture an underlying construct of riskiness. Participants reported high levels of satisfaction with their groups' decision-making processes and the resulting rankings, and these reports were corroborated by regression analyses. Risk rankings were similar across individuals and groups, even though individuals and groups did not always agree on the relative importance of risk attributes. Lower consistency between the risk rankings from the holistic and multiattribute procedures and lower agreement among individuals and groups regarding these rankings were observed for a set of high-variance risks. Nonetheless, the generally high levels of consistency, satisfaction, and agreement suggest that this deliberative method is capable of producing risk rankings that can serve as informative inputs to public risk-management decision making.     

Editors' Introduction: Elicitation of Preferences

Journal of Risk and Uncertainty -     

Social stigma and negative consequences: factors that influence college students' decisions to seek testing for sexually transmitted infections

College students often delay or avoid seeking testing for sexually transmitted infections (STIs), even if the services are readily available. We used in-depth, semistructured interviews to survey 41 college students aged 18 to 23 years about factors that influence decisions about STI testing. We grouped statements into 9 themes that represent influences on the decision. The most frequently mentioned factors were negative consequences of testing and perceived vulnerability to infection; other issues that influenced decision making included perceived benefits, perceived severity of diseases, public knowledge and opinion, social norms, provider characteristics, test-site characteristics, and personal considerations. Social stigmas and negative consequences appear to represent significant barriers to college students' being tested, which could increase the risk of spreading infections to others. Clinicians and health educators should raise students' awareness of the need for screening and should work to reduce the barriers to screening, including social stigmas and negative consequences.     

Travel Risks in a Time of Terror: Judgments and Choices

Shortly after the 2002 terrorist attacks in Bali, readers of Conde Nast Traveler magazine were surveyed regarding their views on the risks of travel to various destinations. Their risk estimates were highest for Israel, and lowest for Canada. Estimates for the different destinations correlated positively with (1) one another, (2) concern over aspects of travel that can make one feel at risk (e.g., sticking out as an American), (3) worries about other travel problems (e.g., contracting an infectious disease), and (4) attitudes toward risk. Respondents' willingness to travel to a destination was predicted well by whether their estimate of its risk was above or below their general threshold for the acceptability of travel risks. Overall, the responses suggest orderly choices, based on highly uncertain judgments of risks. Worry played a significant role in these choices, even after controlling for cognitive considerations, thereby supporting the recently proposed "risk as feelings" hypothesis. Thus, even among people who have generally consistent and defensible beliefs, emotions may affect choices. These results emerged with people selected for their interest in and experience with the decision domain (travel), but challenged to incorporate a new concern (terror).     

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.     

Embedding effects: Stimulus representation and response mode

Thecontingent valuation (CV) methodology assigns prices to environmental amenities by asking people how much they would be willing to pay in order to preserve or acquire those amenities. If this measurement procedure is valid, then responses should be sensitive to relevant changes in the amenities being judged and insensitive to irrelevant changes. One apparent demonstration of inappropriate insensitivity is theembedding effect: the observation that people are apparently willing to pay the same amount of money for a good as for a minor subset of that good. This study examined the possibility that the source of this effect lies with each of two (potentially treatable) methodological problems: 1) subjects have difficulty using quantitative (dollar) response modes to express their values; and 2) subjects have difficulty absorbing the essential details of the CV scenarios describing those goods. The study found that 1) subjects showed considerable embedding both with a simple paired-comparison response mode and with a more demanding one requiring direct dollar estimates; 2) embedding was much reduced with the simpler response mode; 3) subjects' preferences with the two response modes were usually inconsistent; 4) when asked to describe the CV scenario that they had just heard, subjects often reported key task details inaccurately; and 5) there was less embedding when tasks were reinterpreted in terms of the questions subjects reported having answered (as opposed to what had actually been asked). These results are discussed in terms of the match between the questions that investigators would like to ask and the ones that subjects are capable of answering.     

Risk heatmaps as visual displays: Opening movie studios after the COVID-19 shutdown

Upon shutting down operations in early 2020 due to the COVID-19 pandemic, the movie industry assembled teams of experts to help develop guidelines for returning to operation. It resulted in a joint report, The Safe Way Forward, which was created in consultation with union members and provided the basis for negotiations with the studios. A centerpiece of the report was a set of heatmaps displaying SARS-CoV-2 risks for a shoot, as a function of testing rate, community infection prevalence, community transmission rate (R0), and risk measure (either expected number of cases or probability of at least one case). We develop and demonstrate a methodology for evaluating such complex displays, in terms of how well they inform potential users, in this case, workers deciding whether the risks of a shoot are acceptable. We ask whether individuals making hypothetical return-to-work decisions can (a) read display entries, (b) compare display entries, and (c) make inferences based on display entries. Generally speaking, respondents recruited through the Amazon MTurk platform could interpret the display information accurately and make coherent decisions, suggesting that heatmaps can communicate complex risks to lay audiences. Although these heatmaps were created for practical, rather than theoretical, purposes, these results provide partial support for theoretical accounts of visual information processing and identify challenges in applying them to complex settings.