An Iterative Choice Approach to Valuing Clean Lakes,Rivers, and Streams

This article introduces an iterative choice procedure for valuing inland water quality. This approach breaks up the valuation into a series of component tasks. The water quality ladder approach is not valid empirically. Consequently, respondents in Colorado and North Carolina assessed the value of making water quality rated good by EPA, which has a value of $22.40 per additional percent improvement. Nonuse and probabilistic use are highly valued. The results also indicate how water quality valuations differ for aquatic environment, edible fish, and swimming, as well as for water that is cloudy, smelly, or polluted by toxics. Minorities are particularly likely to rely upon monitorable water quality attributes.     

Communication of ambiguous risk information

This paper reports on the responses of 646 individuals to environmental risk information involving different forms of risk ambiguity. Recipients of more than one set of risk information do not simply average the risk levels provided. Rather, a variety of aspects of the nature of the risks that are communicated influence their probabilistic beliefs. Individuals' perceptions of the risk levels to which they are exposed are likely to be greater: (i) for more ambiguous risks, (ii) for risks for which the unfavorable risk evidence is presented last even when there is no temporal order, (iii) for risks for which the most unfavorable risk studies have been performed most recently, and (iv) for risks where there is asymmetry in the risk ambiguity that imposes substantial potential downside risks. Although these effects are modest for the median individual, the potential for extreme responses that reflect only the most adverse or the most favorable piece of information provided is quite prevalent. These findings are of interest more generally in that they indicate how individuals form their risk perceptions in the presence of risk ambiguity.The authors would like to thank the U.S. Environmental Protection Agency for support of this work under Cooperative Agreements Number CR-815445-01-2 and Number CR-814388-02-1. Dr. Alan Carlin and Dr. Ann Fisher provided valuable guidance in the design of the project, and Dr. Doyle Graham and Dr. Douglas Anthony offered generous assistance in communicating the medical consequences of nerve disease to subjects. Jon LaScala assisted superbly in the administration and analysis of the survey, and Patricia Born provided additional computer programming assistance.     

Bayesian decisions with ambiguous belief aversion

This study provides an empirical perspective on the effect of ambiguous environmental risk information on lottery preferences using a sample of 646 adults. The learning process follows a Bayesian expected utility model in terms of the overall magnitude and sign of the weights that respondents place on the risk information. Significant ambiguous belief aversion that is consistent with the Ellsberg paradox is also evident. The extent of this aversion increases with the size of the risk spread, but at a decreasing rate. These results are consistent with both probability-based and preference-based models of ambiguous probabilities. The findings also indicate the presence of cognitive limitations in the processing of risk information, but lead to rejection of more extreme models in which individuals respond in alarmist fashion or do not learn at all.     

Editor's Introduction

Editorial Introduction

Editor's Introduction     

Consumer processing of hazard warning information

Using data obtained from a field experiment involving 957 consumers, this study investigates the linkage between hazard warnings and precautionary behavior, as well as the structure of the information about product usage and risks that consumers store in their memories. Through the use of a methodology based on an open-ended memory recall task, we measure how consumer recall of information on product labels is affected by the type and format of the information and infer the structure by which this information is stored in their memory. The methodology also allows us to explore the importance of limitations on consumers' cognitive abilities. In particular, we find that consumers substitute greater recall of risk information for recall of usage information, indicating a tradeoff among the different types of information conveyed on a product label. We also found that in the case of cluttered labels, as typified by many existing product labels, information overload results, which may make labeling ineffective in achieving its intended informational objective.