The Hindsight Bias: The Role of the Availability Heuristic and Perceived Risk

The influence of outcome knowledge (Fischhoff, 1975) and the availability heuristic (Tversky & Kahneman, 1974) on judgments of perceived risk was explored here. This study found that subjects were capable of making relatively appropriate probability estimates for disease, accident, and homicide in foresight, but they made relatively biased estimated in hindsight. The results suggest that hindsight information activates the use of the availability heuristic on peoples' probability estimates of certain misfortune.     

Contextual determinants of strategic choice: Some moderators of the availability bias

Three studies explored how the influence of the ‘availability heuristic’ on frequency judgement is mediated and moderated by the perceived meaning of the task, the perceived relevance of information for the task, and the salience of differential memorability of information. All studies adapted the ‘fumous names ’paradigm (Tversky and Kahneman, 1973) in which subjects are required to listen to a list of names of known personalities of both sexes and then judge the frequency of men and women. The availability heuristic (Tversky and Kahneman, 1973) posits that classes whose instances are easy to imagine or recall will be perceived as relatively frequent, so that when names of one sex are more famous and thus memorable this category will be rated as more numerous even when it occurs less frequently. Consistent with the notion that the use of availability is sensitive to task interpretation, we showed that the availability effect is eliminated over successive trials (Study 1) and moderated when task instructions render different categories salient (Study 2). In the third study it is shown that conditions which facilitate awareness of the biasing relationship between gender and fame (memorability), decrease the use of the availability heuristic by moderating frequency estimates of the more famous category. Results of these studies emphasize the context-bound and strategic aspects of judgement.     

Story understanding and counterfactual reasoning

D. Kahneman and A. Tversky (1982), in a seminal study on counterfactual reasoning, claimed empirical support for a simulation heuristic wherein ease of converting unusual conditions determines their selection as causes over normal conditions. Discourse analysis of their stories revealed a confounding of explanation and normality. A connectionist simulation of online comprehension and memory access of alternative conditions without conversion accounted for their data. Normality and explanation were varied independently in 2 experiments. Explanation but not normality affected the rank ordering of counterfactual conditions after reading. Access of alternative conditions in simulation was again the best predictor of empirical findings. Comprehension and memory operate where stories communicate information for decision making such as counterfactual reasoning and hindsight bias.     

判断与决策中的情感启发式

情感启发式是指在判断与决策的过程中,个体会有意识或无意识的利用自己对任务选项的主观情感反应来做出决策。具体来说,个体头脑中物体和事件的表征会激起不同水平的情感体验,这种不同的体验会对所有的表征做出积极或消极的标记,人们根据这些被标记的体验来做出判断和决策。情感启发式是个体在决策中常用的策略。目前,关于情感启发式心理机制的解释主要有情感启发式模型和双加工理论。此外,情感启发式的影响因素主要包括经验、时间压力、可评估性和计数能力等。未来的研究应主要集中在探究情感启发式的产生根源和进一步扩展情感启发式应用领域的研究。     

Predictors of perceived susceptibility of breast cancer and changes over time: a mixed modeling approach

OBJECTIVE: To examine predictors of perceived susceptibility to breast cancer and assess differences across three dependent measures. DESIGN: Annual surveys were completed by US women veterans (N = 3,758) participating in a repeat mammography intervention trial. Multivariable non-linear mixed model analyses examined individual- and group-level changes in perceived susceptibility to breast cancer. DEPENDENT MEASURES: Three single-item measures of perceived susceptibility to breast cancer (percent risk, ordinal risk, and comparative risk likelihood). Predictors included demographic, health status, health behavior, affect, knowledge, and subjective norm variables. RESULTS: Breast symptoms and greater cancer worry increased perceived susceptibility for all three measures. Other predictors varied by dependent measure. Random change, indicating individual variability, was observed for percent risk only. CONCLUSION: Despite small model effect sizes, breast symptoms and cancer worry were consistent predictors and may be good targets for messages designed to influence women's perceived susceptibility to breast cancer. Researchers may benefit from using measures of perceived susceptibility with larger response scales, but additional measurement research is needed. Combining indicators of perceived susceptibility may be undesirable when different predictors are associated with different measures.     

Memory accessibility and probability judgments: an experimental evaluation of the availability heuristic.

Consistent with Tversky and Kahneman's (1973, 1974) availability heuristic hypothesis, the current study found a negative correlation between recall latency for past events and the perceived future probability of similar events. Furthermore, when the relative accessibility of memories of positive and negative events was experimentally manipulated using the Velten mood-induction procedure, the perceived future probabilities of similar events also changed in a manner consistent with the availability heuristic account. Reductions in recall latencies resulting from the mood manipulations were, as predicted, related to increases in perceived probability, and vice versa. Partial correlations indicated that this association between the observed patterns of changes in recall latencies and probability judgments could not be accounted for by the existence of independent associations between each of these effects and the magnitude of mood change.     

Counterfactual processing and the correspondence between events and outcomes: Normality versus value

Kahneman and Tversky (1982) have proposed a simulation heuristic such that perceivers tend to substitute ‘normal’ antecedent events for exceptional ones in psychologically ‘undoing’ a given outcome. Recently Gavanski and Wells (1989) have demonstrated that exceptional outcomes tend to be perceived as caused by exceptional events and normal outcomes by normal events, a finding more in line with the representativeness heuristic than this ‘normalization’ principle. We argue that representativeness may be determined by the evaluative tone of events as well as by probability—namely that positive events are assumed to underlie positive outcomes and negative events, negative outcomes. Both normality and value were independently manipulated in order to test the relative effects of each of these factors. In contrast to Gavanski and Wells our data indicate that preference was given to the similarity of value between events and outcome for undoing both positive and negative and normal and exceptional outcomes. Some implications of these findings for counterfactual processing are discussed.     

Meta-analysis of the relationship between risk perception and health behavior: the example of vaccination.

BACKGROUND: Risk perceptions are central to many health behavior theories. However, the relationship between risk perceptions and behavior, muddied by instances of inappropriate assessment and analysis, often looks weak. METHOD: A meta-analysis of eligible studies assessing the bivariate association between adult vaccination and perceived likelihood, susceptibility, or severity was conducted. RESULTS: Thirty-four studies met inclusion criteria (N = 15,988). Risk likelihood (pooled r = .26), susceptibility (pooled r = .24), and severity (pooled r = .16) significantly predicted vaccination behavior. The risk perception-behavior relationship was larger for studies that were prospective, had higher quality risk measures, or had unskewed risk or behavior measures. CONCLUSIONS: The consistent relationships between risk perceptions and behavior, larger than suggested by prior meta-analyses, suggest that risk perceptions are rightly placed as core concepts in theories of health behavior.     

Natural sampling and base-rate neglect

Using an analogue of the lawyer-and-engineer item (Kahneman & Tversky, 1973), we compared conditions in which base rates were either presented as percentages (A), or frequencies (B), to conditions in which the natural sampling process was described additionally (C) or was directly experienced (D). We expected the likelihood of base-rate utilization to increase as the presentation approaches the process of natural sampling. Accordingly, results showed that the contingency of judgments on base rates systematically increased across conditions A to D. © 1998 John Wiley & Sons, Ltd.     

The effect of increasing the memorability of category instances on estimates of category size

According to Tversky and Kahneman’s (1973) availability heuristic, people sometimes make use of the ease with which instances are retrieved when they have to estimate proportions or frequencies. One implication of this availability heuristic is that any factor that affects memorability of instances from a category should also affect the estimated category size. In one of their experiments, Tversky and Kahneman found that, after being presented with a list of names, people judged the more famous names to be more frequent. Similarly, recall was found to be greater for the more famous names. Three experiments that used Tversky and Kahneman’s paradigm are reported. Repeating nonfamous names resulted in their increased recallability and a corresponding increase in estimates of their frequency (Experiments 1 and 3). Making nonfamous names more salient (Experiment 3) also had parallel effects on recallability and frequency estimates, indicating that different memory manipulations affected availability in a similar fashion. Furthermore, reliance on the heuristic was not changed as a function of prior knowledge (Experiment 2) or practice (Experiment 3)     

Cognitive Heuristics and AIDS Risk Assessment Among Physicians1

Physicians (N= 331) reported perceived risk of HIV exposure, worry about on-the-job HIV exposure, and experience with patients who test seropositive for the HIV. In addition, the use of the availability heuristic was examined by responses to questions about talking and reading about AIDS, and the use of the simulation heuristic was examined by responses to questions about imagining oneself being exposed to HIV on the job. Simulation of the HIV-exposure experience related significantly to perceived risk (p < .001), even after variance attributable to actual experience and use of the availability heuristic was taken into account. Availability of AIDS information related marginally to perceived risk after variance attributable to actual experience and use of the simulation heuristic was taken into account. Simulation related strongly with worry about on-the-job exposure (p < .001), and availability was not significantly related to worry after variance associated with simulation and experience with AIDS was removed. Implications of these results for physician training are discussed.     

Predicting adolescent pedestrians’ behavioral intentions to follow the masses in risky crossing situations

Adolescent pedestrians are a major population at risk of being killed or injured in traffic accidents, especially in developing countries. In the current study, we examined the effects of age, gender, sensation seeking, and conformity tendency on Chinese adolescent pedestrians’ intention to cross the road against a traffic signal. A sample of 510 adolescents, aged 12–19 years, completed a series of questionnaires comprising (1) a demographic questionnaire, (2) scales which measured their tendency towards social conformity and sensation seeking, and (3) a questionnaire based on the Theory of Planned Behavior (TPB), which measured their intention to cross the road in two different traffic scenarios. One scenario depicted a situation where the crossing was consistent with other pedestrians’ behavior (Conformity scenario). In the second scenario, the road crossing was inconsistent with other pedestrians (Non-conformity scenario). Along with behavioral intentions, attitudes towards the behavior, subjective norms, perceived behavioral control, anticipated affect, moral norms, and perceived risk were also assessed. In general, adolescent participants reported greater likelihood in crossing the road when other pedestrians were crossing the road as well (Conformity with the masses) and adolescents in middle school were more likely to cross than those in high school. A hierarchical regression model explained 30% of the variance in behavioral intention in the Non-conformity scenario and 40% of the variance in the Conformity scenario. For both scenarios, attitude, subjective norm, perceived behavioral control, and anticipated affect emerged as common predictors. The theoretical and practical implications for these results are discussed.     

Context effects: the proportional difference model and the reflection of preference

The reflection effect (D. Kahneman & A. Tversky, 1979) was investigated using the stochastic model of choice developed by C. Gonzalez-Vallejo (2002). The model assumes that individuals make trade-offs among attribute values by relying on a difference variable. The model also specifies a threshold representing individual proclivities to reach to attribute differences. Two experiments demonstrated that changes in risk attitudes, from a gain to a loss situation, depended on the stimuli as well as on individuals' thresholds. Thresholds were generally lower in losses than in gains, indicating a risk-taking tendency. Thresholds were also lower when participants were endowed with greater savings. Model testing revealed better fits for the stochastic model than cumulative prospect theory (A. Tversky &. D. Kahneman, 1992).     

Causal conjunction fallacies: The roles of causal strength and mental resources

In two experiments we tested the prediction derived from Tversky and Kahneman's (1983) work on the causal conjunction fallacy that the strength of the causal connection between constituent events directly affects the magnitude of the causal conjunction fallacy. We also explored whether any effects of perceived causal strength were due to graded output from heuristic Type 1 reasoning processes or the result of analytic Type 2 reasoning processes. As predicted, Experiment 1 demonstrated that fallacy rates were higher for strongly than for weakly related conjunctions. Weakly related conjunctions in turn attracted higher rates of fallacious responding than did unrelated conjunctions. Experiment 2 showed that a concurrent memory load increased rates of fallacious responding for strongly related but not for weakly related conjunctions. We interpret these results as showing that manipulations of the strength of the perceived causal relationship between the conjuncts result in graded output from heuristic reasoning process and that additional mental resources are required to suppress strong heuristic output.     

Linda问题：“齐当别”抉择模型的解释

大量有关人类归因判断的研究表明,人类经常违反理性概率公理。Tversky和Kahneman（1983）使用Linda问题等特定场景的研究发现,人们系统性地表现出违反理性推断标准,判断合取事件发生概率大于其组成事件发生概率,称之为合取谬误,并用人们使用代表性启发式判断概率来解释该现象产生的原因。然而使用启发式观点对合取谬误现象进行解释过于模糊不清。该文首先介绍了合取谬误现象及其解释模型,然后应用Li（1994,2004）提出的不确定情形下决策理论——“齐当别”抉择模型对Linda问题中合取谬误产生的原因进行了新的解释     

The illusion of certainty: A catastrophe model of decision framing

Tversky and Kahneman (1981) have proposed that decision frames act to bias the processing of decision-relevant information by decision makers. Decision frames act as illusions to which most decision makers are susceptible. We believe that catastrophe theory provides a unique framework by which the effects of decision framing can be studied. Catastrophe theory has been proposed as a way to explain the sudden shifts in preference in perceptual experiments (Stewart & Peregoy, 1983). Tversky and Kahneman’s (1981) decision-framing concept, in decision situations, is proposed to be analogous to the cognitive, organizing centers underlying catastrophic changes in response in perceptual experiments. The results of this study were interpreted as demonstrating the heuristic value of catastrophe theory in describing the decision-framing phenomenon as a cognitive illusion. A version of this paper was presented to the Second Annual Convention of the american Psychological Society, June 7–10, 1990, Dallas, Texas.     

Judgments relative to patterns: how temporal sequence patterns affect judgments and memory

Six experiments studied relative frequency judgment and recall of sequentially presented items drawn from 2 distinct categories (i.e., city and animal). The experiments show that judged frequencies of categories of sequentially encountered stimuli are affected by certain properties of the sequence configuration. We found (a) a first-run effect whereby people overestimated the frequency of a given category when that category was the first repeated category to occur in the sequence and (b) a dissociation between judgments and recall; respondents may judge 1 event more likely than the other and yet recall more instances of the latter. Specifically, the distribution of recalled items does not correspond to the frequency estimates for the event categories, indicating that participants do not make frequency judgments by sampling their memory for individual items as implied by other accounts such as the availability heuristic (Tversky & Kahneman, 1973) and the availability process model (Hastie & Park, 1986). We interpret these findings as reflecting the operation of a judgment heuristic sensitive to sequential patterns and offer an account for the relationship between memory and judged frequencies of sequentially encountered stimuli.     

The role of risk perception and efficacy cognitions in the prediction of HIV-related preventive behavior and condom use

Abstract

Based on empirical findings on the central model variables of the Protection Motivation Theory, the influence of perceived susceptibility, perceived severity of the threat of AIDS, communicative and sexual self-efficacy, and outcome expectancy on various aspects of HIV-preventive behavior was examined. The study was based on a sample of 468 heterosexual adults between the ages of 20 and 45 years. The data were obtained by means of questionnaires filled out at various vacation sites that draw mass tourism or in the subjects' home town. The most significant predictor of behavior was found to be self-efficacy expectancy as regards assertiveness and use of HIV-related preventive measures. A high communicative self-efficacy expectancy, on the other hand, is associated with a higher level of risk behavior among certain subgroups and under certain behavioral aspects. This confirms the necessity of acknowledging the different forms of self-efficacy expectancy in sexual interactions. Perceived personal threat is also associated with risk behavior with respect to certain behavioral operationalizations. From this it can be concluded that one's own behavior is used as the basis for appraising one's susceptibility. The results also show that distinctions must be made when analyzing HIV-related risk behavior. In particular, a difference must be made between absolute behavior (degree of the risk behavior) and relative behavior (change - especially reduction - in risk behavior due to the danger of AIDS).