Biases In Risk Perception Research Articles

Individuals' Estimates of the Risks of Death: Part I--A Reassessment of the Previous Evidence

It is widely argued that individuals have biased perceptions of health and safety risks. A reconsideration of the best-known evidence suggests that this view is the erroneous result of a failure to consider the implications of scarce information. Our findings imply that the hypothesis that people make unbiased estimates of hazard rates fails to be rejected by the very data that were initially used to reject it. Thus, we are able to reconcile the alleged existence of widespread bias in risk perception with other findings that such bias is less apparent in the case of job-related hazards. The seeming bias in estimating population-average death rates and the lack of such bias in assessing job risks are two manifestations of the same behavior, which is the optimal acquisition of costly information. Copyright 1997 by Kluwer Academic Publishers

Government action, biases in risk perception, and insurance decisions : 074075 (E12) Viscusi W.K., Duke University, Durham, The Geneva Papers on Risk and Insurance, Vol. 20, nr. 01, 1995, pp. 93–110

Government action, biases in risk perception, and insurance decisions : 074075 (E12) Viscusi W.K., Duke University, Durham, The Geneva Papers on Risk and Insurance, Vol. 20, nr. 01, 1995, pp. 93–110

Government action, biases in risk perception, and insurance decisions.

Government action, biases in risk perception, and insurance decisions.

Risk Perception and Self-Protective Behavior

Most models of health-related behaviors are based on the assumption that people estimate the seriousness of a risk, evaluate the costs and benefits of action, and then select a course of action that will maximize their expected outcome. Risk refers to the possibility of loss and is generally conceived as consisting of two components: the probability and the severity of negative outcomes. This article focuses on the probability component. First the role of perceived risk in models of health-behavior will be discussed. Possible biases in risk-perception and the role of perceived risk as a determinant of protective behavior are the next issue. This is followed by some methodological considerations about how to measure perceived risk and investigate its role as a behavioral determinant. Next we turn to optimistic biases in comparative risk appraisal and briefly discuss both antecedents and consequences of optimism. Finally we discuss some implications of these findings for programs aiming to change health-related behavior and increase protective action.

Government Action, Biases in Risk Perception, and Insurance Decisions

Biases in risk perception potentially have a large effect on insurance and risk-related behavior. The government can alter these perceptions either through informational programs or controlling the risk. Policies that convey a higher risk level generally have the expected effects on insurance and protective actions, whereas efforts that increase the precision of either the government risk information or private beliefs typically have ambiguous effects. In some cases, the structure of how government policies enter the risk-belief function is consequential. Ascertaining the magnitude of the effects, not simply the direction, also is an important issue. For example, misperceptions have a dramatic effect on the tradeoffs between compensating differentials and the size of the loss but a negligible effect on the tradeoff between compensating differentials and the magnitude of the probability.

Consistencies and Biases in Risk Perception: II. Individual Subjects' Performance

I analyzed intuitive frequency judgments for deaths from 11 well-known causes. Data analysis at individual subjects' level showed that the response-range effect noted in 1994 by Saito, Kawabata, and Yamagishi operates at the individual subjects' level. Also, the response tendencies exhibited by individuals were highly consistent across three different methods of judgment elicitation. Implications for risk-perception research are discussed.

Consistencies and Biases in Risk Perception: I. Anchoring Process and Response-Range Effect

49 undergraduate subjects provided intuitive frequency judgments of deaths due to 11 well-known causes. The responses were collected in three different formats, estimates of the frequency of deaths per 10,000 people in the population, estimates of the frequency of deaths per 100 people, and rank-order of the causes according to the estimated frequencies. Analysis showed that estimated proportions were reliably higher in the “out of 100” format than in the “out of 10,000” format. I argue that processes of anchoring and adjustment underlie this phenomenon. Also, the subjects' response tendencies seemed to maintain consistency across different methods of judgment. Relationship with previous risk-perception research is discussed.

Optimism, Vulnerability, and self-beliefs as health-related cognitions: A systematic overview

Abstract This paper disentangles a number of closely related cognitions by dividing them into the categories of defensive and functional optimism. Optimistic biases in risk perception are discussed that may represent barriers in the adoption of preventive health behaviors. Instead of defensive optimism, some sense of vulnerability is seen as indispensable for behavioral change operating jointly with beliefs about positive health outcomes, instrumental actions, and appropriate coping resources. A distinction is made between three kinds of functional optimism that depend either on attributional style, outcome expectancies, or personal agency. Findings are presented that corroborate the strength of these constructs in predicting health outcomes. In terms of health behavior change, it is argued that optimistic self-beliefs are the most beneficial because of their operative power that helps to set goals, initiate actions, and maintain motivation.

Perceiving AIDS-related risk: accuracy as a function of differences in actual risk.

This study investigates the perceived risk of an HIV infection. Cognitive antecedents of biases in risk perception and their effects on behavioral intentions were investigated. The purpose of this study was to determine the relative accuracy of risk assessments for samples that vary in actual risk for AIDS. Subjects were citizens of Amsterdam, heterosexuals with private partners, gay men, and heterosexuals with prostitution partners. Although optimistically biased in all samples, perceptions of risk were related to previous risk behavior in high-risk samples only. Pessimism was more pronounced in samples higher at risk. Optimists had lower levels of previous risk behavior and increased intentions to adopt safe sex practices. Ss in samples higher at risk had, therefore, relatively adequate perceptions of risk.

Risk perception and behavior: Pessimism, realism, and optimism about aids-related health behavior

Abstract This study investigates the perceived risk of becoming infected with HIV for heterosexuals with multiple sexual partners, examines cognitive and motivational antecedents of biases in risk perception, and relates these biases to behavior. We obtained a moderate degree of optimism in a longitudinal study based on a sample of 535 visitors of a STD clinic. Further analyses—after classifying subjects as “pessimists”, “realists”, or “optimists”—revealed that pessimists were extremely pessimistic and optimists remarkably optimistic. Optimism increased with perceived control and decreased with prior experience, supporting a cognitive explanation of optimism. The data also provided some support for a motivational explanation: optimists who scored higher on a defensive coping style were more optimistic about their risks. Contrary to other findings, we found a positive relation between optimism and intentions to reduce risks. Furthermore, results revealed that optimists showed lower levels of subsequent behavioral risk. It was concluded that optimists were not unrealistically optimistic about their personal vulnerability. but rather that pessimists were unrealistically pessimistic. Previous behavior was found to be the best predictor of subsequent behavior. Although measures of perceived risk were also related to subsequent behavior, their predictive power was rather modest.

A Method for Correcting Biases in Risk Perception

Research in the area of risk perception has shown that people consistently underestimate common risks and overestimate rare ones. This tendency could have an undesirable effect on behavior in potentially hazardous situations. An imaging method was employed for the purpose of changing the perceived risk of a group of potential hazards. The hazards were coffee maker, lawn mower, pesticide, bicycle, power saw, toaster, asbestos, and swimming pool. Subjects sketched cartoons or scenarios of themselves having an accident involving each of a subgroup of the hazards. Subjects rated the risk of each hazard to themselves and estimated injury frequencies for the general population both before and after they sketched the accident scenario. They also rated the hazards on a variety of dimensions such as severity, plausibility, familiarity, imageability, etc. The results indicate that certain characteristics of the hazard determine how likely the risk perception is to change when accident scenarios are made cognitively available.

A Bayesian perspective on biases in risk perception

Psychological risk perception studies have shown that individuals overassess low frequency events and underassess high frequency events. This letter develops a new test that reconciles these findings with the Bayesian learning approach frequently used in economic analysis.