The Overconfidence Phenomenon as a Consequence of Informal Experimenter-Guided Selection of Almanac Items

The paper argues for an ecological approach to realism of confidence in general knowledge. It is stressed that choice of answer to almanac items and confidence judgments derive from knowledge structures formed by adaptation to a natural environment. People are regarded as well-calibrated to their natural environments and the overconfidence phenomenon is seen as a consequence of the procedures involved in the creation of "traditional" general knowledge items, rather than as the result of a cognitive bias. An experiment is reported showing that when items are informally selected by human "selectors," instructed to select items that differentiate between more and less knowledgeable subjects, we observe poor calibration and the usual overconfidence phenomenon. However, when the item selection is "debiased" and the objects to be compared in the almanac items are selected randomly from a natural environment the overconfidence phenomenon disappears and we observe good calibration, and good resolution. These results support an ecological approach to realism of confidence and suggest that general procedures for debiasing overconfidence may be unwarranted.     

Personality differences in hindsight bias

Ten personality correlates of hindsight bias were tested in a study with 75 participants answering almanac-type knowledge questions. Participants showed hindsight bias when hindsight estimates were compared to foresight estimates (memory condition), when hindsight estimates were compared to foresight estimates of other participants (BS = between-subjects hypothetical condition), and when hindsight estimates were compared to foresight estimates in response to equally difficult control items (WS = within-subject hypothetical condition). The magnitude of hindsight bias in both hypothetical conditions was positively associated with the participant's field dependence and his or her tendency for favourable self-presentation (as measured by social desirability and impression management). Between-subjects hypothetical hindsight was associated with the participant's conscientiousness and need for predictability and control (as measured by a rigidity scale). In a multiple regression analysis, 39% of the variance in BS hypothetical hindsight, 24% of the variance in WS hypothetical hindsight, but no significant proportion of the variance in memory hindsight could be accounted for by personality measures. It is concluded that individual differences in hindsight bias exist and must be taken into account in a complete model of the effect.     

Personality differences in hindsight bias

Ten personality correlates of hindsight bias were tested in a study with 75 participants answering almanac-type knowledge questions. Participants showed hindsight bias when hindsight estimates were compared to foresight estimates (memory condition), when hindsight estimates were compared to foresight estimates of other participants (BS = between-subjects hypothetical condition), and when hindsight estimates were compared to foresight estimates in response to equally difficult control items (WS = within-subject hypothetical condition). The magnitude of hindsight bias in both hypothetical conditions was positively associated with the participant's field dependence and his or her tendency for favourable self-presentation (as measured by social desirability and impression management). Between-subjects hypothetical hindsight was associated with the participant's conscientiousness and need for predictability and control (as measured by a rigidity scale). In a multiple regression analysis, 39% of the variance in BS hypothetical hindsight, 24% of the variance in WS hypothetical hindsight, but no significant proportion of the variance in memory hindsight could be accounted for by personality measures. It is concluded that individual differences in hindsight bias exist and must be taken into account in a complete model of the effect.     

Naive empiricism and dogmatism in confidence research: a critical examination of the hard-easy effect

Two robust phenomena in research on confidence in one's general knowledge are the overconfidence phenomenon and the hard-easy effect. In this article, the authors propose that the hard-easy effect has been interpreted with insufficient attention to the scale-end effects, the linear dependency, and the regression effects in data and that the continued adherence to the idea of a "cognitive overconfidence bias" is mediated by selective attention to particular data sets. A quantitative review of studies with 2-alternative general knowledge items demonstrates that, contrary to widespread belief, there is (a) very little support for a cognitive-processing bias in these data; (b) a difference between representative and selected item samples that is not reducible to the difference in difficulty; and (c) near elimination of the hard-easy effect when there is control for scale-end effects and linear dependency.     

Hindsight bias around the world

Hindsight bias refers to the tendency to overestimate in hindsight what one has known in foresight. Recently, two experiments extended the research to include samples from different cultures (Choi & Nisbett, 2000; Heine & Lehman, 1996). Asking their participants what they would have guessed before they knew the outcome ("hypothetical design"), Choi and Nisbett (2000) found that Koreans, in comparison to North Americans, exhibited more hindsight bias. Heine and Lehman (1996), however, reported that Japanese people in comparison to Canadians showed marginally less hindsight bias. In a second study, in which participants were asked to recall what they had estimated before they knew the outcome ("memory design"), the latter authors found no difference in hindsight bias between Japanese people and Canadians. We extended these studies with 225 Internet participants, in a hypothetical design, from four different continents (Asia, Australia, Europe, and North America). Hindsight bias was large and similar for all samples except for German and Dutch participants who showed no hindsight bias at all. While the latter effect may be based on peculiarities of the material and of the participants, the former underscores the worldwide stability of the phenomenon. In addition a follow-up surprise rating (paper and pencil) in China (35 participants) and Germany (20 participants) revealed that only less surprising items led to hindsight bias while more surprising ones did not. We suggest that the basic cognitive processes leading to hindsight bias are by-products of the evolutionary-evolved capacity of adaptive learning. On top of these basic processes, individual meta-cognitions (e.g., elicited by surprise) or motives (e.g., a self-serving motive) may further moderate the amount of bias, thus explaining the diverging results of Choi and Nisbett (2000), Heine and Lehman (1996), and our own study.     

随机截距因子分析模型在控制条目表述效应中的应用

本研究用中文修订版罗森博格自尊量表(RSES-R)考察随机截距因子分析模型在控制条目表述效应时的表现。用RSES-R和过分宣称问卷组成的量表调查621名中学生。结果表明,随机截距模型在建模时,拟合指数良好、因子方差与负荷合理,自尊因子分与RSES-R总分有极高相关,表明该模型能有效分离RSES-R得分的特质与表述效应。分离的表述效应因子分与受测者的自我提升水平具有显著但较弱的相关,表明表述效应与自受测者的社会赞许性有共同的成分。     

Hindsight bias: How knowledge and heuristics affect our reconstruction of the past

Once people know the outcome of an event, they tend to overestimate what could have been anticipated in foresight. Although typically considered to be a robust phenomenon, this hindsight bias is subject to moderating circumstances. In their meta-analysis, Christensen-Szalanski and Willham (1991) observed that the more experience people have with the task under consideration, the smaller is the resulting hindsight bias. This observation is one benchmark against which the explanatory power of process models of hindsight bias can be measured. Therefore, we used it to put the recently proposed RAFT model (Hoffrage, Hertwig, & Gigerenzer, 2000) to another test. Our findings were consistent with the "expertise effect." Specifically, we observed--using computer simulations of the RAFT model--that the more comprehensive people's knowledge is in foresight, the smaller is their hindsight bias. In addition, we made two counterintuitive observations: First, the relation between foresight knowledge and hindsight bias appears to be independent of how knowledge is processed. Second, even if foresight knowledge is false, it can reduce hindsight bias. We conclude with a discussion of the functional value of hindsight bias.     

Hindsight bias: how knowledge and heuristics affect our reconstruction of the past

Once people know the outcome of an event, they tend to overestimate what could have been anticipated in foresight. Although typically considered to be a robust phenomenon, this hindsight bias is subject to moderating circumstances. In their meta-analysis, Christensen-Szalanski and Willham (1991) observed that the more experience people have with the task under consideration, the smaller is the resulting hindsight bias. This observation is one benchmark against which the explanatory power of process models of hindsight bias can be measured. Therefore, we used it to put the recently proposed RAFT model (Hoffrage, Hertwig, & Gigerenzer, 2000) to another test. Our findings were consistent with the "expertise effect." Specifically, we observed-using computer simulations of the RAFT model-that the more comprehensive people's knowledge is in foresight, the smaller is their hindsight bias. In addition, we made two counterintuitive observations: First, the relation between foresight knowledge and hindsight bias appears to be independent of how knowledge is processed. Second, even if foresight knowledge is false, it can reduce hindsight bias. We conclude with a discussion of the functional value of hindsight bias.     

A Meta-Analysis of Research on Hindsight Bias

We conducted a meta-analysis of research on hindsight bias to gain an up-to-date summary of the overall strength of hindsight effects and to test hypotheses about potential moderators of hindsight distortion. A total of 95 studies (83 published and 12 unpublished) were included, and 252 independent effect sizes were coded for moderator variables in 3 broad categories involving characteristics of the study, of measurement, and of the experimental manipulation. When excluding missing effect sizes, the overall mean effect size was Md = .39 with a 95% confidence interval of .36 to .42. Five main findings emerged: (a) effect sizes calculated from objective probability estimates were larger than effect sizes calculated from subjective probability estimates; (b) effect sizes of studies that used almanac questions were larger than effect sizes of studies that used real-world events or case histories; (c) studies that included neutral outcomes resulted in larger effect sizes than studies that used positive or negative outcomes; (d) studies that included manipulations to increase hindsight bias resulted in significantly larger effect sizes than studies in which there were no manipulations to reduce or increase hindsight bias; and (e) studies that included manipulations to reduce hindsight bias did not produce lower effect sizes. These findings contribute to our understanding of hindsight bias by updating the state of knowledge, widening the range of known moderator variables, identifying factors that may activate different mediating processes, and highlighting critical gaps in the research literature.     

后见之明研究综述

后见之明指后见判断(可得益于事件结果反馈的判断)与先见判断(不知晓事件结果时的判断)的系统差异,其研究范式大体可分为两类,假定型设计和记忆型设计。后见效应的研究,具有重大的理论价值和应用价值。文章对后见效应的研究范式、研究结果、及其有关理论进行了简要综述,并对其应用价值加以评述。     

表面概貌对原理运用的影响的实验研究

探讨样例与作业问题的表面概貌相似性对原理运用的影响作用。实验１扩大了Ｒｏｓｓ的研究材料中样例与测题表面概貌方面的差异程度,探讨两者的表面概貌相似性对原理运用的影响。实验２探讨样例与测题在表面概貌的事件类型方面发生改变的条件下,两者的表面概貌相似性对原理运用的影响。实验３探讨在样例与测题表面概貌有两个级别差异的条件下,两者的表面概貌相似性对原理运用的影响。３个实验均采用被试内设计,要求被试学习原理及样例后完成与样例的表面概貌有不同相似关系的测题。结果表明：（１）样例与问题的表面概貌对原理运用有影响,当两者表面概貌发生较大的变化尤其是在表面概貌的事件类型方面发生变化时,其表面概貌相似性对原理运用的影响就会明显地表现出来;（２）样例与问题的表面概貌对原理运用的影响作用,受到两者对象对应性质的制约,当对象对应相似时,其表面概貌相似就会促进解答测题时运用原理,而当两者的对象对应相反时,其表面概貌相似就会对原理运用产生干扰作用。据此可以认为,样例与作业问题表面概貌的相似性,不仅会影响原理的通达,而且也会影响原理的运用。Ｒｏｓｓ关于表面概貌相似与否不影响原理运用的结论应该予以修正。     

模拟法官决策中心理控制源对后见偏差的影响

考察模拟法官决策中心理控制源对后见偏差的影响。实验采用2（心理控制源：外控型、内控型）×3（有无策略：后见组、分散注意组、指导组）两因素被试间实验设计。采用自编两个案例及问卷测查模拟法官决策中后见效应的差异。实验结果发现,不同心理控制源是导致模拟法官决策中后见偏差存在差异的影响因素。同时,两种策略都能够有效减少模拟法官决策中的后见偏差。     

Hindsight bias in political elections

Two studies on political hindsight bias were conducted on the occasions of the German parliament election in 1998 and the Nordrhein-Westfalen state parliament election in 2000. In both studies, participants predicted the percentage of votes for several political parties and recalled these predictions after the election. The observed hindsight effects were stronger than those found in any prior study on political elections (using percentage of votes as the dependent variable). We argue that the length of the retention interval between original judgement and recollection is mainly responsible for this difference. In our second study, we investigated possible artifacts in political hindsight biases using a control-group design where half of the participants recalled their predictions shortly before or after the election. Hindsight bias was preserved, reinforcing the results of earlier studies with non-control-group designs. Finally, we discuss the possibility that the hindsight experience (in political judgement and in general) actually consists of three different, partly independent components.     

Hindsight bias in political elections

Two studies on political hindsight bias were conducted on the occasions of the German parliament election in 1998 and the Nordrhein-Westfalen state parliament election in 2000. In both studies, participants predicted the percentage of votes for several political parties and recalled these predictions after the election. The observed hindsight effects were stronger than those found in any prior study on political elections (using percentage of votes as the dependent variable). We argue that the length of the retention interval between original judgement and recollection is mainly responsible for this difference. In our second study, we investigated possible artifacts in political hindsight biases using a control-group design where half of the participants recalled their predictions shortly before or after the election. Hindsight bias was preserved, reinforcing the results of earlier studies with non-control-group designs. Finally, we discuss the possibility that the hindsight experience (in political judgement and in general) actually consists of three different, partly independent components.     

Signal detection theory with item effects

Applications of signal detection theory (SDT) often involve presentations of different items on each trial, such as slides in a medical imaging study or words in a memory study. If factors particular to the items themselves, apart from being a signal or noise, affect observers’ responses, then ‘item effects’ are present. One way to model these effects is to use a latent continuous variable as an item ‘factor’, such as item ‘difficulty’. Details of SDT models with item effects are clarified via derivations of their implied conditional means, variances, and covariances. Intra-item correlations are defined and suggested as measures of the magnitude of item effects. The SDT-item models are simple random coefficient models and can be fit with standard software. More general models, such as item models with mixing and/or with random observer effects, are also considered.     

Reversibility of the Hindsight Bias: Manipulation of Experimental Demands

A hindsight bias is found when ratings made after outcome feedback differ from ratings made before feedback. Cognitive processes, motivational factors, and demand characteristics have all been identified as possible mediators of the effect. In the first of two experiments, providing subjects with a forewarning with or without a passage that was predicted to have caused it to be ineffective in previous research failed to reduce the bias. Subsequent instructions to produce the bias inflated the effect, whereas instructions to not produce the bias did not alter ratings. In the second experiment, experimental demands were altered by forewarning subjects about a "never-knew-that" effect. The results from Experiment 2 replicated the failure of the forewarning instructions. However, the hindsight bias was removed by instructions to produce a "never-knew-that" effect. The implications of these two experiments for research into the hindsight bias were discussed.     

Hindsight bias in gustatory judgments

Being in hindsight, people tend to overestimate what they had known in foresight. This phenomenon has been studied for a wide variety of knowledge domains (e.g., episodes with uncertain outcomes, or solutions to almanac questions). As a result of these studies, hindsight bias turned out to be a robust phenomenon. In this paper, we present two experiments that successfully extended the domain of hindsight bias to gustatory judgments. Participants tasted different food items and were asked to estimate the quantity of a certain ingredient, for example, the residual sugar in a white wine. Judgments in both experiments were systematically biased towards previously presented low or high values that were labeled as the true quantities. Thus, hindsight bias can be considered a phenomenon that extends well beyond the judgment domains studied so far.     

Question order bias in retrospective evaluations of item and associative recognition

Previous research has demonstrated a retrospective memory bias in metacognitive judgments regarding performance on general knowledge questions: Test-takers rate their own performance more optimistically when tests begin with easy questions than when tests begin with hard questions. An anchoring heuristic has been proposed to explain this finding, in which experience with the early questions constrains global performance evaluations of the test. In the current study we report on two experiments using tasks of item recognition and associative recognition to investigate the generality of question order bias. As predicted by an anchoring explanation, participants’ estimates of performance were higher for item recognition tests beginning with easy items. However, the effect was reversed in the associative recognition task: Participants’ estimates of performance were higher for tests beginning with hard items. Specific recollections, if present, may have a greater impact on test performance perception than more general global impressions.     

"I knew we would win": hindsight bias for favorable and unfavorable team decision outcomes

This study examined hindsight bias for team decisions in a competitive setting in which groups attempted to outperform each other. It was anticipated that, because of self-serving mechanisms, individuals would show hindsight bias only when decision outcomes allowed them to take credit for their own team's success or to downgrade another team for being unsuccessful. MBA students playing a market simulation game made hindsight estimates regarding the likelihood that either their own or another team would perform well. Consistent with a self-serving interpretation, when decision outcomes were favorable individuals evaluating their own team, but not those evaluating another, showed hindsight bias. When outcomes were unfavorable individuals evaluating their own team did not show hindsight bias, but those evaluating another team did. Discussion focuses on implications of hindsight bias in team decision-making settings.     

Hindsight bias demonstrated in the prediction of a sporting event

The authors examined hindsight bias in the context of a sporting event (Super Bowl XXXIII) with individuals who had previous knowledge of the hindsight bias-42 students who were currently enrolled in psychology classes that had previously covered hindsight bias. To control for extraneous variables, the authors analyzed how often the participants watched football, their gender, and whom they predicted to win; they found no differences between how often the participants watched football and whom they predicted to win. The hindsight bias existed for the prediction of the outcome for the Super Bowl, and the participants with previous knowledge were not immune to its effect. Results are discussed in relation to attribution theory, the reconstructionist view, and response bias view.