| This project examined how uncertainty and ethical information influence risk perceptions, risk-reducing behaviors, and moral reasoning about environmental risks. In order to carry out the National Academy of Sciences' call for the inclusion of uncertainty estimates and ethical analyses in environmental risk policy deliberations, there is a need to understand how this information will influence responses to risks. Parallels between theories of moral and risky decision making make it plausible that information about ethical issues and uncertainty might have complex joint influences. Consequentialist theories (e.g., utilitarianism and expected utility) propose that decisions are made by comparing the consequences of different actions and choosing the action that maximizes utility. In non-consequentialist theories (e.g., deontological and emotion-based theories), decisions are based on evaluations of and reactions to actions themselves, rather than the consequences of actions. These theories provided the basis for the hypotheses of the present work, namely that uncertainty and ethical information would alter decision making mechanisms in specific ways that would influence risk perceptions, risk behaviors, and moral reasoning.;Five experiments were conducted in which participants read scenarios about environmental risks (e.g., toxic waste, pesticides). Within these scenarios information about risk uncertainty, probability, and ethical violations was manipulated. Participants made self-report judgments of their risk perceptions, emotional reactions, moral evaluations, and environmental choices. They also responded to a risk-reducing behavior measure and to open-ended questions that were coded for different types of moral reasoning.;Results showed that uncertainty increased risk perceptions and risk-reducing behavior as expected. Also as predicted, information about ethical violations increased negative consequentialist, deontological, and emotional reactions, which in turn predicted higher risk perceptions. However, there was less support for the hypothesis that ethical information would reduce the effect of uncertainty on risk perceptions. In addition, uncertainty led to more consequentialist choices and reasoning rather than less, which directly contradicted a hypothesis. This project extends previous research by demonstrating a causal link between ethical violations and negative risk perceptions, and showing interactive effects between ethical information, uncertainty, and moral reasoning. |
