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Biomedical subjects

D von Winterfeldt

Publications and source records attributed to D von Winterfeldt.

5 recordsLinked to original sources

Tests of consequence monotonicity in decision making under uncertainty.

Consequence monotonicity means that if 2 gambles differ only in 1 consequence, the one having the better consequence is preferred. This property has been sustained in direct comparisons but apparently fails for some gamble pairs when they are ordered in terms of judged monetary certainty equivalents. In Experiments 1 and 3 a judgment procedure was compared with 2 variants of a choice procedure. Slightly fewer nonmonotonicities were found in one of the choice procedures, and, overall, fewer violations occurred than in previous studies. Experiments 2 and 3 showed that the difference was not due to procedural or stimulus presentation differences. Experiment 4 tested a noise model that suggested that the observed violations were due primarily to noise in estimating certainty equivalents, and so, despite some proportion of observed violations, consequence monotonicity cannot be rejected in that case.

Adult

Managing electromagnetic fields from residential electrode grounding systems: a predecision analysis.

Several epidemiological studies have linked exposure to electromagnetic fields (EMFs) with health effects, including leukemia and brain cancer, but the research is still inconclusive. In particular, no clear causal mechanism has been identified by which EMFs may promote cancers. Nevertheless, the concerns raised by the positive epidemiological studies have led to increasing efforts to reduce EMFs from a number of sources. One source of EMFs are home grounding systems that are connected through water pipes in homes to water mains. This paper analyzes whether home owners who are concerned about electromagnetic fields exposure from home grounding systems should take any action to reduce fields. Assuming that the grounding system produces elevated magnetic fields (e.g., 2-3 mG or higher), this study investigates several readily available alternatives and evaluates them with respect to five criteria: risk reduction, cost, fire risk increase, worker risk, and electrical shock risk. Because of the lack of conclusive evidence about an EMF-cancer relationship, this study uses a parameterized approach that makes conditional estimates of health risk depending on future research outcomes and on the nature of the EMF/health effects relationship. This type of analysis, which is called predecision analysis because of its preliminary nature, is therefore highly dependent on a set of assumptions. Nevertheless, this predecision analysis had some fairly clear results. First, waiting for more research or taking a fairly inexpensive corrective action (insulating the water pipe to reduce ground current flow) seem to be the main contenders for the best decision for many different assumptions and parameters. Second, the choice between these two actions is very sensitive to variations in assumptions and parameters. Homeowners who accept the base-case assumptions and parameters of this study should prefer to wait. If any of the base-case parameters are changed to more pessimistic estimates or if psychological concerns (like worry and regret) are considered, then the best action is to insulate the pipe to reduce the current flow through the water pipes.

Construction Materials

Expert judgment in risk analysis and management: process, context, and pitfalls.

The regulation and management of hazardous industrial activities increasingly rely on formal expert judgment processes to provide wisdom in areas of science and technology where traditional "good science" is, in practice, unable to supply unambiguous "facts." Expert judgment has always played a significant, if often unrecognized, role in analysis; however, recent trends are to make it formal, explicit, and documented so it can be identified and reviewed by others. We propose four categories of expert judgment and present three case studies which illustrate some of the pitfalls commonly encountered in its use. We conclude that there will be an expanding policy role for formal expert judgment and that the openness, transparency, and documentation that it requires have implications for enhanced public involvement in scientific and technical affairs.

Expert Testimony

A prescriptive risk framework for individual health and safety decisions.

A conceptual framework is developed for the prescriptive evaluation of health and safety risks to an individual. This framework allows one to compare chronic vs. acute health risks, accidents vs. illness, and physical vs. psychological impacts. To do this, value judgments are necessary to quantify one's health state in terms of both physical and psychological well-being. Probabilities are necessary to describe implications of activities such as skiing or smoking and conditions such as cancer or third-degree burns in terms of these health states. Suggestions are made to operationalize and use the framework to evaluate and compare very different individual health and safety risks. Essentially, all existing measures of individual risk can be derived as special cases of the proposed framework.

Decision Support Techniques

Improving risk communication.

This paper explores reasons for difficulties in communicating risks among analysts, the laypublic, media, and regulators. Formulating risk communication problems as decisions involving objectives and alternatives helps to identify strategies for overcoming these difficulties. Several strategies are suggested to achieve risk communication objectives like improving public knowledge about risks and risk management, encouraging risk reduction behavior, understanding public values and concerns, and increasing trust and credibility.

Communication