We asked how repeated media reports on technological hazards influence an individual’s risk perception. We looked for two contradictory effects, an increasing effect of repetition on perceived risk with the first few repetitions and a decreasing effect with later repetitions, leading to the inverted U-shaped pattern. In an experiment, we demonstrated the inverted U-shaped relationship between the repetition and perceived risk in the context of food risk. The finding broadens the range of mere-exposure effects and indicates that exposure to risk information can be a double-edged sword, which brings either an increasing or a decreasing perceived risk.

We study individual decision making in a lottery-choice task performed by three different populations: gamblers under psychological treatment (“addicts”), gamblers’ spouses (“victims”), and people who are neither gamblers or gamblers’ spouses (“normals”). We find that addicts are willing to take less risk than normals, but the difference is smaller as a gambler’s time under treatment increases. The large majority of victims report themselves unwilling to take any risk at all. However, addicts in the first year of treatment react more than other addicts to the different values of the risk-return parameter.

We study whether experts and novices differ in the way they make predictionsabout National Football League games. In particular, we measure to what extenttheir predictions are consistent with five environmental regularities that couldsupport decision making based on heuristics. These regularities involve the hometeam winning more often, the team with the better win-loss record winning moreoften, the team favored by the majority of media experts winning more often, andtwo others related to surprise wins and losses in the teams’ previousgame. Using signal detection theory and hierarchical Bayesian analysis, we showthat expert predictions for the 2017 National Football League (NFL) seasongenerally follow these regularities in a near optimal way, but novicepredictions do not. These results support the idea that using heuristics adaptedto the decision environment can support accurate predictions and be an indicatorof expertise.

The dual process model of moral judgment (DPM; Greene et al., 2004) argues that such judgments are influenced by both emotion-laden intuition and controlled reasoning. These influences are associated with distinct neural circuitries and different response tendencies. After reanalyzing data from an earlier study, McGuire et al. (2009) questioned the level of support for the dual process model and asserted that the distinction between emotion evoking moral dilemmas (personal dilemmas) and those that do not trigger such intuitions (impersonal dilemmas) is spurious. Using similar reanalysis methods on data reported by Moore, Clark, & Kane (2008), we show that the personal/impersonal distinction is reliable. Furthermore, new data show that this distinction is fundamental to moral judgment across widely different cultures (U.S. and China) and supports claims made by the DPM.

Currently, a disparity exists between the process-level models decision researchers use to describe and predict decision behavior and the methods implemented and metrics collected to test these models. The current work seeks to remedy this disparity by combining the advantages of work in decision research (mouse-tracing paradigms with contingent information display) and cognitive psychology (eye-tracking paradigms from reading and scene perception). In particular, we introduce a new decision moving-window paradigm that presents stimulus information contingent on eye fixations. We provide data from the first application of this method to risky decision making, and show how it compares to basic eye-tracking and mouse-tracing methods. We also enumerate the practical, theoretical, and analytic advantages this method offers above and beyond both mouse-tracing with occlusion and basic eye tracking of information without occlusion. We include the use of new metrics that offer more precision than those typically calculated on mouse-tracing data as well as those not possible or feasible within the mouse-tracing paradigm.

Considerable research has pointed towards processing differences as a viable means for understanding the strength and likelihood of a framing effect. In the current study we explored how differences in processing may emerge through diurnal patters in circadian rhythm, which varies across individuals. We predicted that during circadian off-times, participants would exhibit stronger framing effects whereas framing effects would be relatively weaker during on-times. Six-hundred and eighty five individuals took part in the study; the findings supported our hypothesis, revealing a diurnal pattern of risk responding that varies across the 24-hour circadian cycle.

Individuals often assess themselves as being less susceptible to common biases compared to others. This bias blind spot (BBS) is thought to represent a metacognitive error. In this research, we tested three explanations for the effect: The cognitive sophistication hypothesis posits that individuals who display the BBS more strongly are actually less biased than others. The introspection bias hypothesis posits that the BBS occurs because people rely on introspection more when assessing themselves compared to others. The conversational processes hypothesis posits that the effect is largely a consequence of the pragmatic aspects of the experimental situation rather than true metacognitive error. In two experiments (N = 1057) examining 18 social/motivational and cognitive biases, there was strong evidence of the BBS. Among the three hypotheses examined, the conversational processes hypothesis attracted the greatest support, thus raising questions about the extent to which the BBS is a metacognitive effect.

In this article a broad perspective incorporating elements of time series theory is presented for conceptualizing the data obtained in multi-trial judgment experiments. Recent evidence suggests that sequential context effects, assimilation and contrast, commonly found in psychophysical judgment tasks, may be present in judgments of abstract magnitudes. A time series approach for analyzing single-subject data is developed and applied to expert prognostic judgments of risk for heart disease with an emphasis on detecting possible sequential context effects. The results demonstrate that sequential context effects do exist in such expert prognostic judgments. Contrast and assimilation were produced by cue series; the latter occurring more frequently. Experts also showed assimilation of prior responses that was independent of the cue series input. Time series analysis also revealed that abrupt or large trial-by-trial changes in the value of cues that receive the most attention in prognostic judgment tasks can disrupt the accuracy of these judgments. These findings suggest that a time series approach is a useful alternative to ordinary least squares regression, providing additional insights into the cognitive processes operating during multi-cue judgment experiments.

We experimentally explore the effects of time limitation on decision making. Under different time allowance conditions, subjects are presented with a queueing situation and asked to join one of the two given queues. The results can be grouped under two main categories. The first one concerns the factors driving decisions in a queueing system. Only some subjects behave consistently with rationality principles and use the relevant information efficiently. The rest of the subjects seem to adopt a simpler strategy that does not incorporate some information into their decision. The second category is related to the effects of time limitation on decision performance. A substantial proportion of the population is not affected by time limitations and shows consistent behavior throughout the treatments. On the other hand, some subjects’ performance is impaired by time limitations. More importantly, this impairment is not due to the stringency of the limitation but rather to being exposed to a time constraint.

Studying group decision-making is challenging for multiple reasons. An important logistic difficulty is studying a sufficiently large number of groups, each with multiple participants. Assembling groups online could make this process easier and also provide access to group members more representative of real-world work groups than the sample of college students that typically comprise lab Face-to-Face (FtF) groups. The main goal of this paper is to compare the decisions of online groups to those of FtF groups. We did so in a study that manipulated gain/loss framing of a risky decision between groups and examined the decisions of both individual group members and groups. All of these dependent measures are compared for an online and an FtF sample. Our results suggest that web-conferencing can be a substitute for FtF interaction in group decision-making research, as we found no moderation effects of communication medium on individual or group decision outcome variables. The effects of medium that were found suggest that the use of online groups may be the preferred method for group research. To wit, discussions among the online groups were shorter, but generated a greater number of thought units, i.e., they made more efficient use of time.

In this article, I will show how several observed biases in human probabilistic reasoning can be partially explained as good heuristics for making inferences in an environment where probabilities have uncertainties associated to them. Previous results show that the weight functions and the observed violations of coalescing and stochastic dominance can be understood from a Bayesian point of view. We will review those results and see that Bayesian methods should also be used as part of the explanation behind other known biases. That means that, although the observed errors are still errors under the laboratory conditions in which they are demonstrated, they can be understood as adaptations to the solution of real life problems. Heuristics that allow fast evaluations and mimic a Bayesian inference would be an evolutionary advantage, since they would give us an efficient way of making decisions.

Previous studies have examined the impact of military service on the decision to engage in risky behavior. Yet most of these studies focused on voluntary recruits, did not distinguish between legal and illegal risky activities and did not compare combat and non-combat soldiers during and after service according to gender. The current study is unique because of the nature of Israeli compulsory army service. It examines the relationship between type of army service and five legal and illegal risky behaviors for three groups: non-combat, combat without fighting experience, and combat with fighting experience. We also examine differences in the propensity for risky behavior between men, most of whom are assigned to combat units due to the army’s needs, and women, who serve in combat units on a voluntary basis only. A questionnaire survey was randomly distributed at train stations and central bus stations in Israel among 413 soldiers and ex-soldiers between the ages of 18-30. The predictor variables include type of service or battle experience, the Evaluation of Risks scale and socio-demographic characteristics. In general, we found that high percentages of young people engage in risky behavior, especially illegal behavior. The results indicate that fighting experience is significantly and positively correlated with the consumption of illegal substances for currently serving men soldiers (but not for women) and this effect is mitigated after discharge from the army. Importantly, the use of illegal substances is not a result of the individual’s preferences for engaging in various risky behaviors. Thus, our results suggest that the effect of the increased propensity toward risky behavior following the experience of fighting overrides the combat unit’s discipline for men when it comes to the consumption of illegal substances. In addition, our findings indicate that serving in a combat unit as opposed to a non-combat unit affects the tendency of women ex-combat soldiers to travel to risky destinations, though this is probably related to their original higher risk attitude, since women must volunteer for combat units.

The act of suicide is commonly viewed as wrong in some sense, but it is not clearwhy this is. Based on past empirical research and philosophical theorizing, wetest ten different explanations for why suicide is opposed on normative grounds.Using a within-subjects design, Study 1 showed that seven out of tenmanipulations had significant effects on normative judgments of suicide: timeleft to live, lack of close social relationships, a history of prior immoralbehavior, the manner in which the suicide is committed, painful, incurablemedical issues, impulsive decision-making, and the actor’s ownmoral-religious background. However, in all cases, the act of suicide was stillconsidered wrong, overall. Using a between-subjects design, Study 2 tested thecombined effect of the seven significant manipulations from Study 1. Incombination, the seven manipulations eliminated opposition to suicide, onaverage. Implications for moral psychology and suicide prevention arediscussed.

Economic games offer a convenient approach for the study of prosocial behavior. As an advantage, they allow for straightforward implementation of different techniques to reduce socially desirable responding. We investigated the effectiveness of the most prominent of these techniques, namely providing behavior-contingent incentives and maximizing anonymity in three versions of the Trust Game: (i) a hypothetical version without monetary incentives and with a typical level of anonymity, (ii) an incentivized version with monetary incentives and the same (typical) level of anonymity, and (iii) an indirect questioning version without incentives but with a maximum level of anonymity, rendering responses inconclusive due to adding random noise via the Randomized Response Technique. Results from a large (N = 1,267) and heterogeneous sample showed comparable levels of trust for the hypothetical and incentivized versions using direct questioning. However, levels of trust decreased when maximizing the inconclusiveness of responses through indirect questioning. This implies that levels of trust might be particularly sensitive to changes in individuals’ anonymity but not necessarily to monetary incentives.

We explore different contexts and mechanisms that might promote or alleviate the gender effect in risk aversion. Our main result is that we do not find gender differences in risk aversion when the choice is framed as a willingness-to-accept (WTA) task. When the choice is framed as a willingness-to-pay (WTP) task, men are willing to pay more and thus exhibit lower risk aversion. However, when the choice is framed as a willingness to accept task, women will not accept less than men. These findings imply gender differences in the endowment effect. We also find that the effect size of the gender difference in risk aversion is reduced or eliminated as the context changes from tasks framed as gambles to other domains; and that attitudes toward gambling mediate the gender effect in gambling framed tasks.

It has been argued that individuals behave according to a threshold level of concern decision rule when considering protection against risk: if the perceived probability of the risk is below a threshold level, then the likelihood of the risk is treated as zero and protection is deemed unnecessary. Little is known about the determinants of this threshold nor about whether individual thresholds are related to risk specific emotions like worry and regret. We study threshold probabilities and factors that influence these in the context of flood insurance decision making. Based on data collected from 1,041 Dutch homeowners, we find that on average the threshold level of concern for flood insurance demand is negatively related to the expected regret an individual might feel about not purchasing flood insurance if a flood occurs, as well as to worry about flooding.

Theories of trust distinguish general trust in situations of social uncertainty from assurance-based trust in committed, long-term relationships. This study investigates European-Japanese differences using the Centipede game, in which two players choose between cooperation and defection. The game models repeated reciprocal interactions, necessitating assurance-based trust to sustain cooperation. We included game conditions offering players the option of purchasing commitment-enhancing tools to increase social certainty. Japanese participants were more cooperative than Europeans, confirming higher assurance-based trust, and also purchased more commitment-enhancing tools, demonstrating their preferences for social certainty. Purchase of commitment-enhancing tools improved cooperativeness in both groups. However, if co-players refused tool purchase, the Japanese appeared to interpret this as non-cooperative intent and cooperativeness in the respective games decreased.

A standard way to elicit expectations asks for the percentage chance an event will occur. Previous research demonstrates noise in reported percentages. The current research models a bias; a five percentage point change in reported probabilities implies a larger change in beliefs at certain points in the probability distribution. One contribution of my model is that it can parse bias in beliefs from biases in reports. I reconsider age and gender differences in Subjective Survival Probabilities (SSPs). These are generally interpreted as differences in survival beliefs, e.g., that males are more optimistic than females and older respondents are more optimistic than younger respondents. These demographic differences (in the English Longitudinal Study of Ageing) can be entirely explained by reporting bias. Older respondents are no more optimistic than younger respondents and males are no more optimistic than females. Similarly, in forecasting, information is obscured by taking reported percentages at face value. Accounting for reporting bias thus better exploits the private information contained in reports. Relative to a face-value specification, a specification that does this delivers improved forecasts of mortality events, raising the pseudo R-squared from less than 3 percent to over 6 percent.