Previous research suggests that people may develop stronger causal illusions when the existence of a causal relationship is consistent with their prior beliefs. In the present study, we hypothesized that prior pseudoscientific beliefs will influence judgments about the effectiveness of both alternative medicine and scientific medicine. Participants (N = 98) were exposed to an adaptation of the standard causal illusion task in which they had to judge whether two fictitious treatments, one described as conventional medicine and the other as alternative medicine, could heal the crises caused by two different syndromes. Since both treatments were completely ineffective, those believing that any of the two medicines worked were exhibiting a causal illusion. Participants also responded to the Pseudoscience Endorsement Scale (PES) and some questions about trust in alternative therapies that were taken from the Survey on the Social Perception of Science and Technology conducted by FECYT. The results replicated the causal illusion effect and extended them by revealing an interaction between the prior pseudoscientific beliefs and the scientific/pseudoscientific status of the fictitious treatment. Individuals reporting stronger pseudoscientific beliefs were more vulnerable to the illusion in both scenarios, whereas participants with low adherence to pseudoscientific beliefs seemed to be more resistant to the illusion in the alternative medicine scenario.

Many collaborative online projects such as Wikipedia and OpenStreetMap organize collaboration among their contributors sequentially. In sequential collaboration, one contributor creates an entry which is then consecutively encountered by other contributors who decide whether to adjust or maintain the presented entry. For numeric and geographical judgments, sequential collaboration yields improved judgments over the course of a sequential chain and results in accurate final estimates. We hypothesize that these benefits emerge since contributors adjust entries according to their expertise, implying that judgments of experts have a larger impact compared with those of novices. In three preregistered studies, we measured and manipulated expertise to investigate whether expertise leads to higher change probabilities and larger improvements in judgment accuracy. Moreover, we tested whether expertise results in an increase in accuracy over the course of a sequential chain. As expected, experts adjusted entries more frequently, made larger improvements, and contributed more to the final estimates of sequential chains. Overall, our findings suggest that the high accuracy of sequential collaboration is due to an implicit weighting of judgments by expertise.

Consumers often spend time searching before making a purchasing decision to acquire knowledge about products. If the purchasing decision is delayed, recall of acquired knowledge is likely to be impaired. Because products in the marketplace are rarely described completely, consumers who take too long to decide may fail to notice the absence of information relevant to a purchasing decision and fall prey to a phenomenon called ‘omission neglect’, an inability to detect missing information and form extreme and confidently held judgments. Omission neglect may be corrected by acquiring knowledge about the target product before making the choice. In the present research, we examine consumer decisions in the context of choice sets described incompletely and presented either immediately or a week after the acquisition of relevant information about a target product. Specifically, we investigate how the timing between product knowledge acquisition and decision-making affects the detection of missing information, decision confidence, and choice deferral. Across three experiments, we find that, after acquiring knowledge, when consumers have their decision delayed, they are less able to detect missing information, feel more confident, and defer choices less.

Suppose you need to complete a task of 5 steps, each of which has equal difficulty and pass rate. You somehow have a privilege that can ensure you pass one of the steps, but you need to decide which step to be privileged before you start the task. Which step do you want to privilege? Mathematically speaking, the effect of each step on the final outcome is identical, and so there seems to be no prima facie reason for a preference. Five studies were conducted to explore this issue. In Study 1, participants could place the privilege on any of steps 1–5. Participants were most inclined to privilege step 5. In Study 2, participants needed to pay some money to purchase the privilege for steps 1–5, respectively. Participants would pay most money for step 5. Study 3 directly reminded participants that the probability of success of the whole task is mathematically the same, no matter on which step the privilege is placed, but most of the participants still prefer to privilege the final step. Study 4 supposed that the outcomes of all steps were not announced until all steps were finished, and asked how painful participants would feel if they passed all steps but one. People thought they would feel most painful when they failed at the final step. In Study 5, an implicit association test showed that people associated the first step with easy and the final step with hard. These results demonstrated the phenomenon of the final step effect and suggested that both anticipated painfulness and stereotype may play a role in this phenomenon.

Commitment contracts are a strategy for binding self-control failures, such as skipping a gym visit or breaking a dieting regime, to monetary penalties. Despite evidence that commitment contracts with stronger penalties improve self-control, they are relatively underused. Across 5 experiments, we find that decision makers are less likely to select commitment contracts with more severe penalties (i.e., anti-charity contracts) for themselves than they are for others. This self-other difference in contract choice arises because decision makers believe anti-charity contracts will be more effective for others than for themselves. Our results suggest that people recognize the potential effectiveness of using more aggressive commitment contracts to overcome self-control problems, but view themselves as an exception to that general rule.

We assessed the reaction of American adults to scenarios involving explicit types of exposure to live COVID viruses in June 2020, in the first months of the COVID pandemic. Four features of magical contagion are physical contact focus, insensitivity to elapsed time (‘permanence’), insensitivity to sterilization (‘spiritual essence’), and insensitivity to dose. We demonstrated the operation of all four features in a majority of participants. We also report another dramatic demonstration of the principle of dose insensitivity. When asked for the minimal number of COVID viruses that would have to enter their lung to give them a 50% chance of contracting COVID, more than half of subjects responded with ‘one’. Magical contagion should generally function to increase fear and perceived risk of COVID.

Several papers have challenged the robustness of loss aversion, claiming that it is context-dependent and disappears for small stakes. These papers use a behavioral definition of loss aversion that may be confounded by diminishing sensitivity and probability/event weighting under the new version of prospect theory (PT). We perform a new theory-based test of loss aversion that controls for these confounds. We found significant loss aversion for both small stakes and high stakes. The overall loss aversion coefficient varied between 1.25 and 1.45, less than commonly observed. Loss aversion decreased slightly for small stakes, but the effect was small and usually insignificant. Overall, our results indicate that, under PT, loss aversion is robust to stake size.

Short-sighted decisions can have devastating consequences, and teaching people to make their decisions in a more far-sighted way is challenging. Previous research found that reflecting on one’s behavior can boost learning from success and failure. Here, we explore the potential benefits of guiding people to reflect on whether and how they thought about what to do (i.e., systematic metacognitive reflection). We devised a series of Socratic questions that prompt people to reflect on their decision-making and tested their effectiveness in a process-tracing experiment with a 5-step planning task ( $N=265$ ). Each participant went through several cycles of making a series of decisions and then either reflecting on how they made those decisions, answering unrelated questions, or moving on to the next decision right away. We found that systematic metacognitive reflection helps people discover adaptive, far-sighted decision strategies faster. Our results suggest that systematic metacognitive reflection is a promising approach to boosting people’s decision-making competence.

Philanthropic organizations experience difficulties in obtaining support from younger generations, highlighting the need for modern fundraising strategies. Advances in technology provide a potential solution by offering alternatives to traditional fundraising practices. In an experimental study in collaboration with the International Committee of the Red Cross (ICRC), we investigated whether virtual reality (VR) could be harnessed to innovate fundraising. We customized a VR module developed by the ICRC and tested its effectiveness at eliciting donations compared to that of an on-screen version of the experience. In addition, we explored mechanisms that might drive this effect, namely the level of interactivity (active/passive) and the type of affect elicited by the module (positive—happy ending/negative—tragic ending), as well as subjective perceptions and emotions related to the experience. Our findings showed that VR, compared with an on-screen experience, led to both an increase in incentivized donations and a larger reported propensity to become regular donors. Investigating the mechanisms that might drive the effect, we found that the VR experience led to stronger emotional feelings (notably being moved and sadness) and improved quality of the experience (e.g., level of interest and vividness). We further found physiological evidence showing a significant increase in arousal for the VR condition compared with the on-screen condition, although this was not correlated with an increase in donations. Taken together, our study provides evidence that VR could be a viable tool to innovate fundraising and identifies some of the features that may make this medium more effective than traditional practices.

To investigate the impact of framing on rule-breaking in social dilemmas, we incorporated a rule in a 1-shot resource game with 2 framing treatments: in one frame, we offered a give-some dilemma (i.e., a variant of a public goods game), and in the other frame, a take-some dilemma (i.e., a variant of a commons dilemma game). In each frame, all participants were part of 1 single collective sharing a common good. Each participant was initially equipped with 1 of 5 different endowments of points from which they must give/were allowed to take amounts to/from the common good. The rule established outcome equality between participants by prescribing the exact amounts of what to give/take to/from the common good, which was finally divided equally among participants. Participants decided whether to cooperate and comply with the rule or to break the rule to their own advantage and to the detriment of the collective (i.e., giving lower/taking higher amounts). The results of an online experiment with 202 participants showed a significantly higher proportion of individuals breaking the rule in the take-some dilemma than in the give-some dilemma. In addition, endowment size influenced the proportion of rule-breaking behavior in the take-some dilemma. However, the average amounts of points not given/taken too much were not different between the 2 dilemma types.

There is growing concern about the extent to which economic games played in the laboratory generalize to social behaviors outside the lab. Here, we show that it is possible to make a game much more predictive of field behavior by bringing contextual elements from the field to the lab. We report three experiments where we present the same participants with different versions of the dictator game and with two different field situations. The games are designed to include elements that make them progressively more similar to the field. We find a dramatic increase in lab–field correlations as contextual elements are incorporated, which has wide-ranging implications for experiments on economic decision making.

Numeracy—the ability to understand and use numeric information—is linked to good decision-making. Several problems exist with current numeracy measures, however. Depending on the participant sample, some existing measures are too easy or too hard; also, established measures often contain items well-known to participants. The current article aimed to develop new numeric understanding measures (NUMs) including a 1-item (1-NUM), 4-item (4-NUM), and 4-item adaptive measure (A-NUM). In a calibration study, 2 participant samples (n = 226 and 264 from Amazon’s Mechanical Turk [MTurk]) each responded to half of 84 novel numeracy items. We calibrated items using 2-parameter logistic item response theory (IRT) models. Based on item parameters, we developed the 3 new numeracy measures. In a subsequent validation study, 600 MTurk participants completed the new numeracy measures, the adaptive Berlin Numeracy Test, and the Weller Rasch-Based Numeracy Test, in randomized order. To establish predictive and convergent validities, participants also completed judgment and decision tasks, Raven’s progressive matrices, a vocabulary test, and demographics. Confirmatory factor analyses suggested that the 1-NUM, 4-NUM, and A-NUM load onto the same factor as existing measures. The NUM scales also showed similar association patterns to subjective numeracy and cognitive ability measures as established measures. Finally, they effectively predicted classic numeracy effects. In fact, based on power analyses, the A-NUM and 4-NUM appeared to confer more power to detect effects than existing measures. Thus, using IRT, we developed 3 brief numeracy measures, using novel items and without sacrificing construct scope. The measures can be downloaded as Qualtrics files (https://osf.io/pcegz/).