Interrupted time-series graphs are often judged by eye. Such a graph might show, for example, patient symptom severity (y) on each of several days (x) before and after a treatment was implemented (interruption). Such graphs might be prone to systematic misjudgment because of serial dependence, where random error at each timepoint persists into later timepoints. An earlier study (Matyas & Greenwood, 1990) showed evidence of systematic misjudgment, but that study has often been discounted due to methodological concerns. We address these concerns and others in two experiments. In both experiments, serial dependence increased mistaken judgments that the interrupting event led to a change in the outcome, though the pattern of results was less extreme than in previous work. Receiver operating characteristics suggested that serial dependence both decreased discriminability and increased the bias to decide that the interrupting event led to a change. This serial dependence effect appeared despite financial incentives for accuracy, despite feedback training, and even in participants who had graduate training relevant to the task. Serial dependence could cause random error to be misattributed to real change, thereby leading to judgments that interventions are effective even when they are not.

The classic preference reversal phenomenon, where monetary evaluations contradict risky choices, has been argued to arise due to a focus on outcomes during the evaluation of alternatives, leading to overpricing of long-shot options. Such an explanation makes the implicit assumption that attentional shifts drive the phenomenon. We conducted an eye-tracking study to causally test this hypothesis by comparing a treatment based on cardinal, monetary evaluations with a different treatment avoiding a monetary frame. We find a significant treatment effect in the form of a shift in attention toward outcomes (relative to probabilities) when evaluations are monetary. Our evidence suggests that attentional shifts resulting from the monetary frame of evaluations are a driver of preference reversals.

A growing body of research indicates that forecasting skill is a unique and stable trait: forecasters with a track record of high accuracy tend to maintain this record. But how does one identify skilled forecasters effectively? We address this question using data collected during two seasons of a longitudinal geopolitical forecasting tournament. Our first analysis, which compares psychometric traits assessed prior to forecasting, indicates intelligence consistently predicts accuracy. Next, using methods adapted from classical test theory and item response theory, we model latent forecasting skill based on the forecasters’ past accuracy, while accounting for the timing of their forecasts relative to question resolution. Our results suggest these methods perform better at assessing forecasting skill than simpler methods employed by many previous studies. By parsing the data at different time points during the competitions, we assess the relative importance of each information source over time. When past performance information is limited, psychometric traits are useful predictors of future performance, but, as more information becomes available, past performance becomes the stronger predictor of future accuracy. Finally, we demonstrate the predictive validity of these results on out-of-sample data, and their utility in producing performance weights for wisdom-of-crowds aggregations.

In decision making, people may rely on their own information as well as oninformation from external sources, such as family members, peers, or experts.The current study investigated how these types of information are used bycomparing four decision strategies: 1) an internal strategy that relies solelyon own information; 2) an external strategy that relies solely on theinformation from an external source; 3) a sequential strategy that relies oninformation from an external source only after own information is deemedinadequate; 4) an integrative strategy that relies on an integration of bothtypes of information. Of specific interest were individual and developmentaldifferences in strategy use. Strategy use was examined via Bayesian hierarchicalmixture model analysis. A visual decision task was administered to children andyoung adolescents (N=305, ages 9–14). Individual differences but noage-related changes were observed in either decision accuracy or strategy use.The internal strategy was dominant across ages, followed by the integrative andsequential strategy, respectively, while the external strategy was extremelyrare. This suggests a reluctance to rely entirely on information provided byexternal sources. We conclude that there are individual differences but notdevelopmental changes in strategy use pertaining to perceptual decision-makingin 9- through 14-year-olds. Generalizability of these findings is discussed withregard to different forms of social influence and varying perceptions of theexternal source. This study provides stepping stones in better understanding andmodeling decision making processes in the presence of both internal and externalinformation.

Organizations tasked with communicating expert judgments couched in uncertainty often use numerically bounded linguistic probability schemes to standardize the meaning of verbal probabilities. An experiment (N = 1,202) was conducted to ascertain whether agreement with such a scheme was better when probabilities were presented verbally, numerically or in a combined “verbal + numeric” format. Across three agreement measures, the numeric and combined formats outperformed the verbal format and also yielded better discrimination between low and high probabilities and were less susceptible to the fifty-fifty blip phenomenon. The combined format did not confer any advantage over the purely numeric format. The findings indicate that numerically bounded linguistic probability schemes are an ineffective means of communicating information about probabilities to others and they call into question recommendations for use of the combined format for delivering such schemes.

Intertemporal choices involve tradeoffs between outcomes that occur at different times. Most of the research has used pure gains tasks and the discount rates yielding from those tasks to explain and predict real-world behaviors and consequences. However, real decisions are often more complex and involve mixed outcomes (e.g., sooner-gain and later-loss or sooner-loss and later-gain). No study has used mixed gain-loss intertemporal tradeoff tasks to explain and predict real-world behaviors and consequences, and studies involving such tasks are also scarce. Considering that tasks involving a combination of gains and losses may yield different discount rates and that existing pure gains tasks do not explain or predict real-world outcomes well, this study conducted two experiments to compare the discount rates of mixed gain-loss intertemporal tradeoffs with those of pure gains or pure losses (Experiment 1) and to examine whether these tasks predicted different real-world behaviors and consequences (Experiment 2). Experiment 1 suggests that the discount rate ordering of the four tasks was, from highest to lowest, pure gains, sooner-loss and later-gain, pure losses, and sooner-gain and later-loss. Experiment 2 indicates that the evidence supporting the claim that the discount rates of the four tasks were related to different real-world behaviors and consequences was insufficient.

Many popular books and articles that purport to explain how people, companies, orideas succeed highlight a few successes chosen to fit a particular narrative. Weinvestigate what effect these highly selected “success narratives”have on readers’ beliefs and decisions. We conducted a large, randomized,pre-registered experiment, showing participants successful firms with foundersthat all either dropped out of or graduated college, and asked them to makeincentive-compatible bets on a new firm. Despite acknowledging biases in theexamples, participants’ decisions were very strongly influenced by them.People shown dropout founders were 55 percentage points more likely to bet on adropout-founded company than people who were shown graduate founders. Mostreported medium to high confidence in their bets, and many wrote causalexplanations justifying their decision. In light of recent concerns about falseinformation, our findings demonstrate how true but biased information canstrongly alter beliefs and decisions.

In the face of economic inequalities, redistribution of wealth is a key debate for society, and understanding the reasons why individuals may support more or less redistribution can inform this debate. Here we investigate the mechanisms by which experiencing success in a task decreases the support for redistribution of the wealth generated by the task, such that overachievers favor less redistribution than underachievers. In a laboratory experiment, we replicate this effect and explore how it that may be mediatedby an in-group bias, or by changes in individuals’ principles of redistributive justice. Critically, both in-group favoritism and self-serving adjustments of justice principles partially accounted for the effect of status on redistribution choices. Our study thus sheds new light on the various ways by which economic experience affects support for redistribution.

The MPG illusion and the time-saving bias both show that people misjudge the gains from increases in efficiency or speed, because people falsely believe that efficiency and speed are linearly related to consumption (e.g., gallons of fuel or journey time). This efficiency-consumption gap (ECG) has been demonstrated consistently in various situations. In parallel, people have also been found to show a diminished sensitivity to increases in magnitudes when judged under separate vs. joint evaluation modes (SE vs. JE). We show that these “two wrongs can make a right”: when people judge efficiency upgrades under SE mode, their subjective judgments follow a concave curve that closely resembles the curvilinear pattern of efficiency upgrades, making their preferences (artificially) less biased than they are under JE. In two studies we show that when asked for their willingness-to-pay (WTP) for upgrading products or services in two (a smaller vs. a larger) upgrade options, WTPs are less different in SE vs. JE modes. This means that people are exhibiting lower sensitivity to the upgrade size under SE which leads to a de-biasing effect. We show that because JE follow a linear trend, it yields biased preferences for efficiency measures, but not for consumption measures. In contrast, SE yield biased preferences for consumption, but not for efficiency measures.

Due to the information overload in today’s digital age, people maysometimes feel pressured to process and judge information especially fast. Inthree experiments, we examined whether time pressure increases therepetition-based truth effect — the tendency to judge repeatedlyencountered statements more likely as “true” than novelstatements. Based on the Heuristic-Systematic Model, a dual-process model in thefield of persuasion research, we expected that time pressure would boost thetruth effect by increasing reliance on processing fluency as a presumablyheuristic cue for truth, and by decreasing knowledge retrieval as a presumablyslow and systematic process that determines truth judgments. However, contraryto our expectation, time pressure did not moderate the truth effect.Importantly, this was the case for difficult statements, for which most peoplelack prior knowledge, as well as for easy statements, for which most people holdrelevant knowledge. Overall, the findings clearly speak against the conceptionof fast, fluency-based truth judgments versus slow, knowledge-based truthjudgments. In contrast, the results are compatible with a referential theory ofthe truth effect that does not distinguish between different types of truthjudgments. Instead, it assumes that truth judgments rely on the coherence oflocalized networks in people’s semantic memory, formed by both repetitionand prior knowledge.

The strategy method is a powerful method for eliciting conditional cooperation instrategic interactions. Theoretically, players’ cooperation conditionalon a specific level of others’ cooperation using the strategy methodshould be equal to their unconditional cooperation given an equivalent beliefabout others’ cooperation. However, using the Prisoner’s Dilemma,we show that decisions using the strategy method are more selfish than decisionsunder a simultaneous decision protocol predicted from players’ beliefs.This is driven entirely by lower cooperation among conditional cooperators withlow expectations about others’ cooperation. We further show that relativeto simultaneous choice, the strategy method shifts salient norms from anegalitarian fairness norm (‘give half’) to a reciprocity norm(‘match others’ behaviour’). This undermines cooperationamong players with low beliefs about others’ cooperation. These resultsthus show that the strategy method does not merely hold beliefs constant, butalso shifts which salient norms influence choice behaviour. This has importantimplications for the use of the strategy method in eliciting socialpreferences.

Governments use taxes to discourage undesired behaviors and encourage desired ones. One target of such interventions is reckless behavior, such as texting while driving, which in most cases is harmless but sometimes leads to catastrophic outcomes. Past research has demonstrated how interventions can backfire when the tax on one reckless behavior is set too high whereas other less attractive reckless actions remain untaxed. In the context of experience-based decisions, this undesirable outcome arises from people behaving as if they underweighted rare events, which according to a popular theoretical account can result from basing decisions on a small, random sample of past experiences. Here, we reevaluate the adverse effect of overtaxation using an alternative account focused on recency. We show that a reinforcement-learning model that weights recently observed outcomes more strongly than than those observed in the past can provide an equally good account of people’s behavior. Furthermore, we show that there exist two groups of individuals who show qualitatively distinct patterns of behavior in response to the experience of catastrophic outcomes. We conclude that targeted interventions tailored for a small group of myopic individuals who disregard catastrophic outcomes soon after they have been experienced can be nearly as effective as an omnibus intervention based on taxation that affects everyone.

In “Risky choice framing: Task versions and a comparison of prospect theory and fuzzy-trace theory”, Kühberger and Tanner (2010) examined the impacts of removing stated zero/non-zero complements of risky options on the gain/loss framing effect. They also tested two rival theoretical explanations for this effect: prospect theory and fuzzy-trace theory. The present study aimed to examine the reliability and robustness of the evidence provided by Kühberger and Tanner by precise replication in Study 1. The original findings were reported for conditions in which the probability of the risky option was fixed, and the expected value of the two alternatives was approximately equivalent. The present study also aimed to examine the generality of their findings under additional conditions in which large, medium and small probabilities of the risky option were assigned, and the expected value of the certain or risky options differed. The main findings of Kühberger and Tanner (2010) were successfully replicated and confirmed under the original and additional conditions. The implications of these findings are discussed.

A core principle in decision science is that people choose according to theirsubjective values. These values are often measured using unincentivized scaleswith arbitrary units (e.g., from 0 to 10) or using incentivizedwillingness-to-pay (WTP) with dollars and cents. What is unclear is whetherusing WTP actually improves choice predictions. In two experiments, we comparethe effects of three different subjective valuation procedures: anunincentivized rating scale, the same scale with incentives, and incentivizedWTP. We use these subjective values to predict behavior in a subsequent binaryfood-choice task. The unincentivized rating task performed better than theincentivized WTP task and no worse than the incentivized rating task. Thesefindings challenge the view that subjective valuation tasks need to beincentivized. At least for low-stakes decisions, commonly used measures such asWTP may reduce predictive power.

Disgust is a cross-culturally recognized emotion that is characterized by avoidant or cautious tendencies. Accordingly, greater sensitivity to disgust may be related to less willingness to take risks. Relatively little research has examined the association between disgust sensitivity and risk-taking propensity. Further, no research to date has taken a domain specific approach to understanding the association between these constructs. Across two studies (N1=98, N2=390) and a mini-meta analysis utilizing two additional datasets (total N=1981), we assessed the extent to which domain specific disgust sensitivity (i.e., Pathogen, Sexual, and Moral) were related to domain specific risk-taking propensity (i.e., Social, Recreational, Health/Safety, Ethical, and Financial). We conducted two cross-sectional studies, with a community and a student sample. Participants completed surveys that included measures of disgust sensitivity and risk-taking propensity. Bivariate correlations across the two studies indicated that greater disgust sensitivity was related to lower risk-taking propensity across almost all domains. However, when controlling for covariance among the disgust sensitivity domains, regression analyses suggested variability in the association between disgust sensitivity and risk-taking propensity depending on domains. Based on mini meta-analysis, sexual disgust sensitivity had the strongest relationships with social risk-taking propensity and health/safety risk-taking propensity, and moral disgust sensitivity had the strongest relationship with ethical risk-taking propensity. These findings suggest the presence of domain specific relations between disgust sensitivity and risk-taking propensity. The domain specific focus may help in utilizing disgust as a factor to decrease certain risky behaviors (e.g., moral disgust for decreasing plagiarism).

The attraction effect in multialternative decision making reflects the context-dependent violation of rational choice axioms. This study examined the effect of concurrent divided attention in three-alternative visual choice tasks. The concurrent divided attention task is considered to consume the mental resources available for the choice task. There were three conditions: (a) the task-relevant condition, in which the auditory task should consume resources across multiple levels; (b) the task-irrelevant condition, in which the auditory stimuli should consume perceptual resources; (c) and the control condition, in which the resources should not be consumed by auditory stimuli. Thirty-three participants solved 24 hypothetical purchase problems with three alternatives that differed in terms of two attributes. The results indicated that the choice proportion of the target was significantly higher in the task-relevant condition than in the task-irrelevant and control conditions, thereby suggesting that a reduction in cognitive (and/or response) resources is critical for the attraction effect.

Measuring risk preferences using monetary incentives is costly. In the field, it might be also unfair and unsafe. The commonly used measure of Holt and Laury (2002) relies on a dozen lottery choices and payments, which make it time consuming and expensive. It also raises moral concerns as a result of the unequal payments generated by good and bad luck. Paying some but not all subjects may also create tensions between the researcher and subjects. In a pre-registered study in Honduras, Nigeria and Spain, we use a short version of Holt and Laury where we address all three concerns. We find in the field that not paying at all or paying with and without probabilistic rules makes no difference. Our hypothetical and short version makes our measurement of risk cheaper, fairer and safer.

Experiments are increasingly moving online. This poses a major challenge forresearchers who rely on in-lab techniques such as eye-tracking. Researchers incomputer science have developed web-based eye-tracking applications (WebGazer;Papoutsaki et al., 2016) but they have yet to see them used in behavioralresearch. This is likely due to the extensive calibration and validationprocedure, inconsistent temporal resolution (Semmelmann & Weigelt, 2018),and the challenge of integrating it into experimental software. Here, weincorporate WebGazer into a JavaScript library widely used by behavioralresearchers (jsPsych) and adjust the procedure and code to reducecalibration/validation and improve the temporal resolution (from 100–1000ms to 20–30 ms). We test this procedure with a decision-making study onAmazon MTurk, replicating previous in-lab findings on the relationship betweengaze and choice, with little degradation in spatial or temporal resolution. Thisprovides evidence that online web-based eye-tracking is feasible in behavioralresearch.

The scale distortion theory of anchoring argues that people are influenced by a previously considered numeric value, an anchor, because the anchor distorts the scale on which a subsequent judgment is made. The distortion of the scale due to the anchor is a momentary effect that would be overridden if the scale was distorted again, for example, by consideration of a different value on the same scale. In the present study, participants compared thirteen random anchors on the same scale to thirteen different objects. Subsequent numeric estimates of objects’ attributes were influenced by the corresponding anchors even though the anchors were divided from the estimates by twelve questions pertaining to different values on the same scale. The numeric value considered immediately before the estimate did not have a considerable effect on the judgment. While the anchoring effect was robust, it cannot be easily explained by scale distortion. Other possible theories of the anchoring effect are compatible with the results.

When people are given quantified information (e.g., ‘there is a 60% chance of rain’), the format of quantifiers (i.e., numerical: ‘a 60% chance’ vs. verbal: ‘it is likely’) might affect their decisions. Previous studies with indirect cues of judgements and decisions (e.g., response times, decision outcomes) give inconsistent findings that could support either a more intuitive process for verbal than numerical quantifiers or a greater focus on the context (e.g., rain) for verbal than numerical quantifiers. We used two pre-registered eye-tracking experiments (n(1) = 148, n(2) = 133) to investigate decision-making processes with verbal and numerical quantifiers. Participants evaluated multiple verbally or numerically quantified nutrition labels (Experiment 1) and weather forecasts (Experiment 2) with different context valence (positive or negative), and quantities (‘low’, ‘medium’, or ‘high’ in Experiment 1 and ‘possible’, ‘likely’, or ‘very likely’ in Experiment 2) presented in a fully within-subjects design. Participants looked longer at verbal than numerical quantifiers, and longer at the contextual information with verbal quantifiers. Quantifier format also affected judgements and decisions: in Experiment 1, participants judged positive labels to be better in the verbal compared to the equivalent numerical condition (and to be worse for negative labels). In Experiment 2, participants decided on rain protection more for a verbal forecast of rain than the equivalent numerical forecast. The results fit the explanation that verbal quantifiers put more focus on the informational context than do numerical quantifiers, rather than prompting more intuitive decisions.