People often overestimate their understanding of how things work. For instance, people believe that they can explain even ordinary phenomena such as the operation of zippers and speedometers in greater depth than they really can. This is called the illusion of explanatory depth. Fortunately, a person can expose the illusion by attempting to generate a causal explanation for how the phenomenon operates (e.g., how a zipper works). This might be because explanation makes salient the gaps in a person’s knowledge of that phenomenon. However, recent evidence suggests that people might be able to expose the illusion by instead explaining a different phenomenon. Across three preregistered experiments, we tested whether the process of explaining one phenomenon (e.g., how a zipper works) would lead someone to report knowing less about a completely different phenomenon (e.g., how snow forms). In each experiment, we found that attempting to explain one phenomenon led participants to report knowing less about various phenomena. For example, participants reported knowing less about how snow forms after attempting to explain how a zipper works. We discuss alternative accounts of the illusion of explanatory depth that might better fit our results. We also consider the utility of explanation as an indirect, non-confrontational debiasing method in which a person generalizes a feeling of ignorance about one phenomenon to their knowledge base more generally.

How do emerging technologies affect nuclear stability? In this paper, we use a quasi-experimental cyber-nuclear wargame with 580 players to explore three hypotheses about emerging technologies and nuclear stability: (1) technological uncertainty leads to preemption and escalation; (2) technological uncertainty leads to restraint; and (3) technological certainty leads to escalation through aggressive counterforce campaigns. The wargames suggest that uncertainty and fear about cyber vulnerabilities create no immediate incentives for preemptive nuclear use. The greater danger to strategic stability lies in how overconfidence in cyber exploits incentivizes more aggressive counterforce campaigns and, secondarily, how vulnerabilities encourage predelegation or automation. Both of these effects suggest worrisome relationships between cyber exploits and inadvertent nuclear use on one hand and cyber vulnerabilities and accidental nuclear use on the other hand. Together, these findings reveal the complicated relationship between pathways to escalation and strategic stability, highlighting the role that confidence and perhaps-misplaced certainty—versus uncertainty and fear—play in strategic stability.

Survey respondents over-forecast inflation: they expect it to be higher than itturns out to be. Furthermore, people are generally overconfident in theirforecasts. In two experiments, we show that providing outcome feedback thatinforms people of the actual level of the inflation that they have forecastreduces both over-forecasting and overconfidence in forecasts. Theseimprovements were preserved even after feedback had been withdrawn, a findingthat indicates that they were not produced because feedback had a temporaryincentive effect but because it had a more permanent learning effect. However,providing forecasters with more outcome feedback did not have a greater effect.Feedback appears to provide people with information about biases in theirjudgments and, once they have received that information, no additional advantageis obtained by giving it to them again. Reducing over-forecasting also had noclear effect on overall error. This was because providing outcome feedback afterevery judgment also affected the noise or random error in forecasts, increasingit by a sufficient amount to cancel out the benefits provided by the reductionin over-forecasting.

In a series of three experiments, participants made inferences about which one of a pair of two objects scored higher on a criterion. The first experiment was designed to contrast the prediction of Probabilistic Mental Model theory (Gigerenzer, Hoffrage, & Kleinbölting, 1991) concerning sampling procedure with the hard-easy effect. The experiment failed to support the theory’s prediction that a particular pair of randomly sampled item sets would differ in percentage correct; but the observation that German participants performed practically as well on comparisons between U.S. cities (many of which they did not even recognize) than on comparisons between German cities (about which they knew much more) ultimately led to the formulation of the recognition heuristic. Experiment 2 was a second, this time successful, attempt to unconfound item difficulty and sampling procedure. In Experiment 3, participants’ knowledge and recognition of each city was elicited, and how often this could be used to make an inference was manipulated. Choices were consistent with the recognition heuristic in about 80% of the cases when it discriminated and people had no additional knowledge about the recognized city (and in about 90% when they had such knowledge). The frequency with which the heuristic could be used affected the percentage correct, mean confidence, and overconfidence as predicted. The size of the reference class, which was also manipulated, modified these effects in meaningful and theoretically important ways.

The calibration of probability or confidence judgments concerns the association between the judgments and some estimate of the correct probabilities of events. Researchers rely on estimates using relative frequencies computed by aggregating data over observations. We show that this approach creates conceptual problems, and may result in the confounding of explanatory variables or unstable estimates. To circumvent these problems we propose using probability estimates obtained from statistical models—specifically mixed models for binary data—in the analysis of calibration. We illustrate this methodology by re-analyzing data from a published study and comparing the results from this approach to those based on relative frequencies. The model-based estimates avoid problems with confounding variables and provided more precise estimates, resulting in better inferences.

Right-wing ideology and cognitive ability, including objective numeracy, have been found to relate negatively. Although objective and subjective numeracy correlate positively, it is unclear whether subjective numeracy relates to political ideology in the same way. Replicating and extending previous research, across two samples of American adults (ns= 455, 406), those who performed worse on objective numeracy tasks scored higher on right-wing authoritarianism (RWA) and social dominance orientation (SDO), and they self-identified as more conservative on general, social, and economic continua. Controlling for objective numeracy, subjective numeracy related positively to measures of right-wing ideologies. In other words, those who strongly (vs. weakly) endorsed right-wing ideologies believed they are good with numbers yet performed worse on numeracy tasks. We discuss implications for the opposing direction of associations between ideology with objective versus subjective numeracy and similarities with literature on overconfidence.

Many natural decisions contain an element of skill. Modern conceptions of the skill component include control (Goodie, 2003) and competence (Heath & Tversky, 1991). The control hypothesis states that a task's skill component (the sensitivity of the task to skill) affects decision making; the competence hypothesis states decision making is affected only if the participant possesses the skill. Three experiments compared risk taking patterns between two groups. One group faced bets on random events, and another group faced bets on their answers to general knowledge questions, which is a task characterized by control. In Experiment 1, control increased risk taking markedly with all statistical properties held constant. In Experiment 2, decisions made in domains of varying difficulty, and by individuals of varying ability, yielded further qualified support for the role of competence. In Experiment 3, the role of control was replicated, and participants’ perceptions of the differences in group treatments aligned more with the implications of the control hypothesis than with the competence hypothesis. Results offered support for the control hypothesis across a range of competence.

This research investigated how different forms of overconfidence correlate with age. Contrary to stereotypes that young people are more overconfident, the results provide little evidence that overestimation of one’s performance or overplacement of one’s performance relative to that of others is correlated with age. Instead, the results suggest that precision in judgment (confidence that one knows the truth) increases with age. This result is strongest for probabilistic elicitations, and not present in quantile elicitations or reported confidence intervals. The results suggest that a lifetime of experience, rather than leading to better calibration, instead may increase our confidence that we know what we’re talking about.

Subjects who judged speed in a driving scenario overestimated how fast they could decelerate when speeding compared to when keeping within the speed limit (Svenson, 2009). The purpose of the present studies were to replicate studies conducted in Europe with subjects in the U.S., to study the influence of speed unit (kph vs. mph), affective reactions to outcome (collision) and identity of main actor (driver) on braking speed judgments. The results replicated the European findings and the outcome affective factor (passing a line/killing a child) and the actor factor (subject/driver in general) had significant effects on judgments of braking speed. The results were related to psychological theory and applied implications were discussed.

Overprecision is the most robust type of overconfidence. We present a new method that significantly reduces this bias and offers insight into its underlying cause. In three experiments, overprecision was significantly reduced by forcing participants to consider all possible outcomes of an event. Each participant was presented with the entire range of possible outcomes divided into intervals, and estimated each interval’s likelihood of including the true answer. The superiority of this Subjective Probability Interval Estimate (SPIES) method is robust to range widths and interval grain sizes. Its carryover effects are observed even in subsequent estimates made using the conventional, 90% confidence interval method: judges who first made SPIES judgments considered a broader range of values in subsequent conventional interval estimates as well.

Patients suffering from the behavioral variant of Frontotemporal Dementia (FTD-b) often exaggerate their abilities. Are those errors in judgment limited to domains in which patients under-perform, or do FTD-b patients overestimate their abilities in other domains? Is overconfidence in FTD-b patients domain-specific or domain-general? To address this question, we asked patients at early stages of FTD-b to judge their performance in two domains (attention, perception) in which they exhibit relatively spared abilities. In both domains, FTD-b patients overestimated their performance relative to patients with Dementia of Alzheimer Type (DAT) and healthy elderly subjects. Results are consistent with a domain-general deficit in metacognitive judgment. We discuss these findings in relation to “regression to the mean” accounts of overconfidence and the role of emotions in metacognitive judgments.

Errors in estimating and forecasting often result from the failure to collect and consider enough relevant information. We examine whether attributes associated with persistence in information acquisition can predict performance in an estimation task. We focus on actively open-minded thinking (AOT), need for cognition, grit, and the tendency to maximize or satisfice when making decisions. In three studies, participants made estimates and predictions of uncertain quantities, with varying levels of control over the amount of information they could collect before estimating. Only AOT predicted performance. This relationship was mediated by information acquisition: AOT predicted the tendency to collect information, and information acquisition predicted performance. To the extent that available information is predictive of future outcomes, actively open-minded thinkers are more likely than others to make accurate forecasts.

We apply the principles of the “Wisdom of Crowds (WoC)” to improve the calibration of interval estimates. Previous research has documented the significant impact of the WoC on the accuracy of point estimates but only a few studies have examined its effectiveness in aggregating interval estimates. We demonstrate that collective probability intervals obtained by several heuristics can reduce the typical overconfidence of the individual estimates. We re-analyzed data from Glaser, Langer and Weber (2013) and from Soll and Klayman (2004) and applied four heuristics Averaging, Median, Enveloping, Probability averaging-suggested by Gaba, Tsetlin and Winkler (2014) and new heuristics, Averaging with trimming and Quartiles. We used the hit rate and the Mean Squared Error (MSE) to evaluate the quality of the methods. All methods reduced miscalibration to some degree, and Quartiles was the most beneficial securing accuracy and informativeness.

This paper focuses on the effects of entrepreneurial overconfidence at new venture creation. By analyzing Global Entrepreneurship Monitor data and using the theory of planned behavior as a framework, the study provides new evidence on the relative or absolute nature of overconfidence in entrepreneurial skills and the effect of overprecision on new venture creation. Overprecision of supporting beliefs is newly linked to venture creation and it is shown that nascent entrepreneurs’ overconfidence is based on a self-focusing attitude. The results confirm that overconfidence is not a single construct and highlights the differences between the forms of overconfidence habitually confused in the entrepreneurship literature.