Perceived Event Frequency and the Optimistic Bias: Evidence for a Two-Process Model of Personal Risk Judgments

People often judge themselves to be at lower risk for various negative life events than are their peers. The two empirical studies presented here show that the magnitude of this optimistic bias can be either negatively or positively related to the perceived frequency of the event, depending on whether people judge their own risk relative to that of an average peer (make comparative risk judgments) or judge their own and an average peer's risk separately (make absolute risk judgments). A new two-process model is presented to account for these results. The model combines a better-than-average heuristic with elements of the singular target-focused and singular- distributional models of Klar and colleagues (Klar & Giladi, 1997, 1999; Klar, Medding, & Sarel, 1996). The empirical results and model have many implications for the study of personal risk judgments, the optimistic bias, and risk-taking behavior.     

Perceived Control and the Optimistic Bias: A Meta-Analytic Review

People consistently believe that negative events are less likely to happen to them than to others. Research suggests a relationship between this optimistic bias and perceived control such that the greater control people perceive over future events, the greater their optimistic bias. We conducted a meta-analysis of 27 independent samples to quantify the size of this relationship and examine what variables moderated the relationship. Greater perceived control was significantly related to greater optimistic bias, but this relationship was moderated by participant nationality, student status, risk status, and the type of optimistic bias measure used. We discuss the findings in the context of primary versus secondary control.     

Optimisme comparatif dans le milieu professionnel : l'influence de la fréquence et de la gravité sur la perception des risques d'accident du travail

The aim of this study is to test if people express comparative optimism when they evaluate their risk of being confronted to various work accidents compared to their colleagues. We also test the assumption according to which individuals are as much more optimistic as the event is threatening. Thus, an accident which is serious and probable (and consequently more threatening) should generate a maximum of comparative optimism. Our population is composed by employees of a mirror manufacture company. The latter evaluated their personal risk and that of one of their colleagues to be confronted with a severe /rare, severe/frequent, non severe/rare or non severe/frequent accident. Our results reveal the presence of an optimistic bias and this particularly for the severe and frequent accident. These data are discussed in terms of defensive bias and self esteem maintenance.     

Automatic optimism: Biased use of base rate information for positive and negative events

People generally judge that positive events will occur in their lives and negative events will not, even when both events have the same objective likelihood to occur. In four studies, we examined the possibility that this optimistic bias is the result of people’s automatic affective reactions to future events. Studies 1 and 2 demonstrate, in two different contexts, that people are consistently optimistic in their predictions, despite identical base rates for positive and negative events. In Study 2, optimistic bias was not influenced by incentives for motivated reasoning or rewards for accuracy, suggesting that bias was the result of automatic processes. Studies 3 and 4 showed that optimistic bias was more pronounced when predictions were speeded and when participants made predictions after exposure to affectively valenced words. Together, these findings suggest that people optimistically interpret base rates and that this optimism is due to an effortless affective process.     

Testing the limits of optimistic bias: event and person moderators in a multilevel framework

N. D. Weinstein (1980) established that optimistic bias, the tendency to see others as more vulnerable to risks than the self, varies across types of event. Subsequently, researchers have documented that this phenomenon, also known as comparative optimism, also varies across types of people. The authors integrate hypotheses originally advanced by Weinstein concerning event-characteristic moderators with later arguments that such optimism may be restricted to certain subgroups. Using multilevel modeling over 7 samples (N = 1,436), the authors found that some degree of comparative optimism was present for virtually all individuals and events. Holding other variables constant, higher perceived frequency and severity were associated with less comparative optimism, higher perceived controllability and stereotype salience with more comparative optimism. Frequency, controllability, and severity were associated more with self-risk than with average-other risk, whereas stereotype salience was associated more with average-other risk than with self-risk. Individual differences also mattered: comparative optimism was related negatively to anxiety and positively to defensiveness and self-esteem. Interaction results imply that both individual differences and event characteristics should jointly be considered in understanding optimistic bias (or comparative optimism) and its application to risk communication.     

The typical student as an in‐group member: eliminating optimistic bias by reducing social distance

While demonstrations of optimistic bias are plentiful, successful attempts at eliminating the bias (debiasing) are rare. The current study attempted to debias by reducing the perceived social distance between the self and the typical own university student. Using self‐categorisation theory, it was predicted that rating the out‐group target (the typical student at another university) before the in‐group one would reduce the perceived social distance between the self and the latter and lead to a reduction in optimistic bias. Both predictions were supported, with optimistic bias being eliminated for negative events and attenuated for positive events. In the standard optimistic bias condition (in‐group first) optimistic bias was obtained for both negative and positive events. The findings provide support for perceived social distance in determining optimistic bias. The implications for recent arguments that comparisons with an abstract target automatically evoke an ‘I am better than average’ heuristic or necessarily entail the use of distributional judgmental frameworks are explored. Whilst the automatic linking of abstract targets with heuristic or distributional thinking is called into question, a case is made for integrating these ideas with the self‐categorisation approach. Where practitioners aim to reduce optimistic bias, the findings suggest promoting the perception of the target as a fellow in‐group member may help do so. Copyright © 2000 John Wiley & Sons, Ltd.     

Effects of contingencies of self‐worth and sensitivity to indebtedness on optimistic bias in seeking help for depression

The occurrence of the optimistic bias in seeking help for depressive symptoms has been attributed to the threat‐to‐self and equity theories. The current study tested the hierarchical relationships between contingencies of self‐worth (CSW), self‐esteem (SE), sensitivity to indebtedness (SI), and optimistic bias in seeking formal/informal help for depression. An online questionnaire survey was conducted with Japanese university students (n = 1000). Results from structural equation modeling analysis revealed the mediating effect of CSW on SE and optimistic bias. SI was positively related to optimistic bias in symptom recognition and informal help‐seeking. The results suggest that both CSW and SI are responsible for the occurrence of optimistic bias in seeking help for depression. Cognitive patterns in recognizing personal and others' depressive symptoms and needs for seeking help were discussed.     

Unrealistic optimism about future life events: a cautionary note

A robust finding in social psychology is that people judge negative events as less likely to happen to themselves than to the average person, a behavior interpreted as showing that people are "unrealistically optimistic" in their judgments of risk concerning future life events. However, we demonstrate how unbiased responses can result in data patterns commonly interpreted as indicative of optimism for purely statistical reasons. Specifically, we show how extant data from unrealistic optimism studies investigating people's comparative risk judgments are plagued by the statistical consequences of sampling constraints and the response scales used, in combination with the comparative rarity of truly negative events. We conclude that the presence of such statistical artifacts raises questions over the very existence of an optimistic bias about risk and implies that to the extent that such a bias exists, we know considerably less about its magnitude, mechanisms, and moderators than previously assumed.     

Optimism and pessimism as predictors of change in health after death or onset of severe illness in family.

The authors prospectively examined changes in health after a major life event (death or onset of severe illness in family) among 5,007 employees (mean age=44.8 years) whose optimism and pessimism levels were assessed in 1997 and major life events in 2000. Health was indicated by sickness absence days during a period covering 36 months prior to the event and 18 months after the event. Increase in sick days after the event was smaller and returned to the prevent level more quickly among highly optimistic individuals than among their counterparts with low optimism. Parallel changes were not observed in relation to pessimism. These findings suggest that optimism may reduce the risk of health problems and may be related to a faster recovery after a major life event.     

大学生对艾滋病的乐观偏差

研究采用问卷法,以北京6所高校的278名被试为样本,考察了大学生对艾滋病的乐观偏差。结果表明,被试对艾滋病的感染和治愈存在着双重乐观偏差;艾滋病知识掌握程度既与感染艾滋病的乐观偏差无显著相关,也与治愈艾滋病的乐观偏差无显著相关。     

Overcoming the planning fallacy through willpower: effects of implementation intentions on actual and predicted task‐completion times

Previous work has shown that people often underestimate their task‐completion times (Buehler, Griffin, & Ross, 1994 ). The present research examined whether this optimistic bias may be reduced through the formation of implementation intentions. In an experimental study, participants were requested to complete an assignment within a specified time period. Half of these participants made implementation intentions about where and when they would complete the assignment. The remaining participants were simply given the goal of completing the assignment. The results showed that furnishing participants' goals with implementation intentions led to (a) more optimistic completion predictions, (b) an even greater increase in actual rates of goal completion, and, consequently, (c) a significant reduction in optimistic bias in completion predictions. Furthermore, the reduction in optimistic bias among implementation–intention participants was found to be mediated by a smaller number of interruptions while working on the assignment. Together, these findings attest to the importance of implementation planning in overcoming unrealistic optimism in task‐completion predictions. Copyright © 2000 John Wiley & Sons, Ltd.     

Collaborative planning and prediction: Does group discussion affect optimistic biases in time estimation?

Intuition and previous research indicate that individuals commonly display an optimistic bias in time prediction. The present studies extend research on task completion forecasts to examine tasks performed collaboratively by groups, and predictions generated through group discussion. Participants predicted—individually and collaboratively—when they would complete upcoming group projects ranging from brief laboratory tasks to extensive real-world projects, and their actual completion times were measured. Results supported the three guiding hypotheses. First, there was an optimistic bias for both individual (Studies 1 and 2) and group predictions (Studies 1–3). Second, predictions generated through group discussion were more optimistic than those generated individually. Third, this “group accentuation” effect was mediated by the informational focus at the time of prediction. Group discussion heightened participants’ tendency to focus primarily on factors promoting successful task completion, and this selective focus on “planning for success” enhanced their optimistic outlook. Discussion centers on theoretical contributions to the individual and group decision making literatures, as well as applied implications for planning and forecasting within organizational contexts.     

Coping and physical health outcomes: an overview

The aim of the present study was to investigate longitudinally the sensitivity of optimistic beliefs (positive outcome expectancies, efficacy expectancies, and optimistic bias) to disease-related stress (measured by disease duration, depressive symptoms, physical symptoms, physical impairment, and life-events) in Type 1 diabetes (n = 90) and multiple sclerosis (n = 90). First, we examined whether chronically ill patients were less optimistic than a healthy control group (n = 60), which showed that patients reported lower levels of optimistic bias but similar levels of the two other optimistic beliefs. Next, we analyzed the stability of the three types of optimistic beliefs across time (one year) for both disease groups, which demonstrated that optimistic bias in MS patients decreased. Finally, the impact of disease-related stressors on optimistic beliefs during a one-year period was determined, showing that all three optimistic beliefs decreased when patients reported depressive symptoms. Together, these findings show that positive outcome expectancies and efficacy expectancies were unaffected by being ill and fairly stable unless patients reported depressive symptoms while optimistic bias appeared to decrease as a result of being ill. Results are discussed in terms of the role of control and depression in optimistic bias.     

Depressive symptoms are associated with unrealistic negative predictions of future life events

This study examined the relationship between depressive symptoms and bias in the prediction of future life events. Responding to internet announcements, 153 participants varying widely in self-reported depression symptom severity estimated the probability of 40 events occurring over the succeeding 30 days. After the 30-day period, participants reported which events occurred. Optimistic/pessimistic biases were related to level of depressive symptoms. A non-significant optimistic bias characterized participants with low depressive symptoms whereas a significant pessimistic bias characterized participants with high depressive symptoms. Those reporting mild symptoms did not exhibit a systematic pessimistic or optimistic bias. General imprecision in predictions for undesirable events was associated with depressive symptoms. These findings suggest that depression is associated with pessimistic bias rather than accuracy in judgment.     

解释水平视角下的乐观偏差效应

研究基于解释水平理论,考查心理距离对乐观偏差效应的影响。实验从心理距离的事件概率维度、时间距离维度、空间距离维度入手,采用自编的材料对677名被试进行测量,探讨心理距离的远近对乐观偏差产生的影响。结果表明,被试对未来生活事件的判断存在总体上的乐观偏差。在较远的心理距离条件下,被试表现出更大的乐观偏差;而在较近的心理距离中,乐观偏差效应明显减小。但在时间距离维度以及消极事件的概率维度上,表现出与总体乐观偏差不一致的现象。     

Heart attack risk perception biases among hypertension patients: the role of educational level and worry

Risk biases such as comparative optimism (thinking one is better off than similar others) and risk inaccuracy (misestimating one's risk compared to one's calculated risk) for health outcomes are common. Little research has investigated racial or socioeconomic differences in these risk biases. Results from a survey of individuals with poorly controlled hypertension (N=813) indicated that participants showed (1) comparative optimism for heart attack risk by underestimating their heart attack risk compared to similar others, and (2) risk inaccuracy by overestimating their heart attack risk compared to their calculated heart attack risk. More highly educated participants were more comparatively optimistic because they rated their personal risk as lower; education was not related to risk inaccuracy. Neither race nor the federal poverty level was related to risk biases. Worry partially mediated the relationship between education and personal risk. Results are discussed as they relate to the existing literature on risk perception.     

Pessimistic explanatory style and response to illness

Previous studies have shown that a pessimistic explanatory style is a risk factor for illness, but the factors linking explanatory style and illness are unknown. One's characteristic response to poor health may mediate this relationship. Perhaps pessimistic individuals act helplessly in the face of their symptoms, thereby exacerbating disease. In the present study, we investigated this possibility by asking 96 young adults to complete measures of explanatory style, habitual response to illness, and ways of coping during their most recent episode of illness. Subjects who explain bad events pessimistically (with internal, stable, and global causes) reported more frequent illnesses during the past year and rated their overall health more poorly than those who habitually favor external, unstable, and specific explanations. When ill, the pessimistic subjects were less likely than their optimistic counterparts to take active steps to combat their illness. Our results suggest that one pathway leading from pessimistic explanatory style to poor health is mundane: passivity in the face of disease.     

Perspectives on prediction: Does third-person imagery improve task completion estimates?

People typically underestimate the time necessary to complete their tasks. According to the planning fallacy model of optimistic time predictions, this underestimation occurs because people focus on developing a specific plan for the current task and neglect the implications of past failures to meet similar deadlines. We extend the classic planning fallacy model by proposing that a phenomenal quality of mental imagery – the visual perspective that is adopted – may moderate the optimistic prediction bias. Consistent with this proposal, participants in four studies predicted longer completion times, and thus were less prone to bias, when they imagined an upcoming task from the third-person rather than first-person perspective. Third-person imagery reduced people’s focus on optimistic plans, increased their focus on potential obstacles, and decreased the impact of task-relevant motives on prediction. The findings suggest that third-person imagery helps individuals generate more realistic predictions by reducing cognitive and motivational processes that typically contribute to bias.     

Academic optimistic bias: Implications for college student performance and well-being

Although optimism has several benefits, there are potential drawbacks associated with “too much of a good thing”. Within an academic context, a possible determinant of the adaptiveness of optimistic bias is whether students have a sense of control over academic outcomes: optimistically-biased (OB) achievement expectations paired with perceptions of academic control may enhance performance and well-being; optimistic bias in the absence of perceived control may result in disappointment, poor performance, and diminished well-being. The current longitudinal study examined academic control cognitions (ACC) among OB college students (n = 319) versus non-optimistically biased (non-OB) students (n = 321). We also examined the effects of academic optimistic bias on composite measures of college performance (perceived success, final psychology course grades, cumulative GPA, course attrition) and well-being (positive and negative emotions, health behaviors, future optimism) 6 months later; and determined whether ACC accounted for those associations. Significant MANCOVAs showed OB students had greater ACC, better subsequent well-being, and outperformed their non-OB counterparts. These well-being and performance differences remained significant after statistically accounting for initial aptitude and ACC. Overall, academic optimistic bias was accompanied by perceived controllability over scholastic outcomes, yet beyond the effects of ACC, optimistic bias was associated with better year-end performance and well-being. Findings have implications for maximizing the successful transition of first-year college students.     

When Is Difficult Planning Good Planning? The Effects of Scenario‐Based Planning on Optimistic Prediction Bias

As a general rule, individuals tend to be optimistic in predicting when they will complete an upcoming activity. Building upon the ease of generation theory, we examined how dividing the planning process into multiple steps would impact the magnitude of optimism in “real world” planning. In Experiment 1 we found a decrease in optimistic prediction bias when individuals described their plans by generating a relatively difficult five‐step, rather than a relatively easy two‐step, optimistic scenario. In Experiment 2 the bias diminished when individuals generated the easy, rather than difficult, pessimistic scenario. In Experiment 3 the bias decreased even among individuals who generated the easy, rather than difficult, optimistic scenario when they were led to negatively interpret the feeling of ease.