Designing Risk Communications: Completing and Correcting Mental Models of Hazardous Processes, Part I

Many risk communications are intended to help the lay public make complex decisions about risk. To guide risk communicators with this objective, a mental models approach to the design and characterization of risk communications is proposed. Building on text comprehension and mental models research, this approach offers an integrated set of methods to help the risk communication designer choose and analyze risk communication content, structure, and organization. An applied example shows that two radon brochures designed with this approach present roughly the same expert facts as a radon brochure widely distributed by the U.S. EPA but meet higher standards on other content, structure, and organization criteria.     

What Do We Know About Making Risk Comparisons?

The risks of unfamiliar technologies are often evaluated by comparing them with the risks of more familiar ones. Such risk comparisons have been criticized for neglecting critical dimensions of risky decisions. In a guide written for the Chemical Manufacturers Association, Covello et al. (¹) have summarized these critiques and developed a taxonomy that characterizes possible risk comparisons in terms of their acceptability (or objectionableness). We asked four diverse groups of subjects to judge the acceptability of 14 statements produced by Covello et al. as examples of their categories. We found no correlation between the judgments of acceptability produced by our subjects and those predicted by Covello et al. .     

Judged Terror Risk and Proximity to the World Trade Center

In November 2001, a nationally representative sample of Americans (N = 973, ages 13–88), queried via WebTVs at home, judged the probability of five terror-related events (e.g., being injured in an attack) and three “routine” risks (e.g., being a victim of other violent crime), in the following 12 months. Judgments of terror risks, but not routine risks, were related to whether respondents were within 100 mi of the World Trade Center. This relationship was found only in the following demographic groups, and not their complements: men, adults, whites, and Republicans. These differential responses to risk have both theoretical and policy implications.     

Counting casualties: A framework for respectful,useful records

Counting casualties in conflict zones faces both practical and ethical concerns. Drawing on procedures from risk analysis, we propose a general approach. It represents each death by standard features, having either essential value, for capturing the social and cultural meaning of individual casualties, or instrumental value, for relating patterns of casualties to possible causes and effects. We illustrate the approach with the choices involved in attempts to record casualties in Iraq and the Israel-Palestine conflict, and with natural disasters, as exemplified by Hurricane Katrina. We advocate institutionalizing the approach, so that recording casualties increases understanding, rather than suspicion.

Understanding long-term environmental risks

How well we manage long-term environmental risks depends on how well we understand them. Whether the risk managers are experts or laypeople, that understanding is typically limited. As a result, people must rely on judgment when making decisions about risks. Estimating how big risks are and how much reducing them is worth is an intellectual skill. After reviewing the behavioral principles that govern how people acquire such skills, this article offers several proposals for facilitating learning abut risks by improving the ways in which scientific data are created or presented. It also describes some pitfalls facing attempts to determine the quality of other people's understanding of risks, whether through direct study or more casual observation.Preparation of this article was supported by National Science Foundation Grant SES-8846459. It is gratefully acknowledged. The opinions expressed are those of the author.     

Measuring values: A conceptual framework for interpreting transactions with special reference to contingent valuation of visibility

People express their value for a good when they pay something for it. Interpretinggood andpayment very broadly, we offer a general analytical framework for characterizing such transactions. This framework is suitable for interpreting actual transactions as well as for creating hypothetical transactions for research purposes. It is described here both in general terms and with special application to one particular kind of transaction, contingent valuation studies in which individuals estimate the value of possible changes in atmospheric visibility. In these transactions, as in many others, risk (of undesired changes in visibility) is one principal feature; at least some uncertainty often surrounds other transaction features as well (For example: How much will visibility really change if I promise to pay for it? Will I really have to pay?). The framework presented here conceptualizes any transaction as involving (a) a good, (b) a payment, and (c) a social context within which the transaction is conducted. Each of these aspects in turn has a variety of features that might and in some cases should affect evaluations. For each such feature, the framework considers first the meaning of alternative specifications and then the difficulties of ensuring that they are understood and evaluated properly. As a whole, the framework provides an integrated approach to designing evaluation studies and interpreting their results.     

What Risks Are People Concerned About

An unusual questionnaire was used to explore what risks concern laypeople. It asked respondents to list, in their own words, as many risks of personal concern as they could. They then selected the five risks of greatest concern and answered a set of specific questions about each. A coding scheme was developed for categorizing these responses and was shown to have good reliability. The questionnaire was administered to a heterogeneous convenience sample of subjects. They reported a very broad range of risks of concern, which differed in plausible ways as a function of their gender and age. Females and student-age subjects were generally more concerned about the environment, whereas males and older subjects were more likely to mention health and safety risks. Both the extent of the risk-reduction actions that they reported and their expressed willingness to pay for future risk reductions were greater for risk that presented a direct personal threat (e.g., health risks) than for risks that posed a diffuse threat to the environment or to people in general (e.g., pollution). Respondents perceived themselves as bearing primary responsibility for managing threats to their own health, but generally saw government as bearing a heavier responsibility for managing environmental risks (especially for pollutants) and war. The questionnaire instrument and coding structure developed for this work are well-suited to a variety of future research applications. They provide a way to identify the risks that concern lay groups, as well as to track the evolution of those concerns over time.     

Risk Communication Planning for the Aftermath of a Plague Bioattack

We create an influence diagram of how a plague bioattack could unfold and then use it to identify factors shaping infection risks in many possible scenarios. The influence diagram and associated explanations provide a compact reference that allows risk communicators to identify key messages for pre‐event preparation and testing. It can also be used to answer specific questions in whatever unique situations arise, considering both the conditions of the attack and the properties of the attacked populations. The influence diagram allows a quick, visual check of the factors that must be covered when evaluating audience information needs. The documentation provides content for explaining the resultant advice. We show how these tools can help in preparing for crises and responding to them.