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.

We present the Concordant-Ranks (CR) strategy that decision makers use to quickly find an alternative that is proximate to an ideal alternative in a multi-attribute decision space. CR implies that decision makers prefer alternatives that exhibit concordant ranks between attribute values and attribute weights. We show that, in situations where the alternatives are equal in multi-attribute utility (MAU), minimization of the weighted Euclidean distance (WED) to an ideal alternative implies the choice of a CR alternative. In two experiments, participants chose among, as well as evaluated, alternatives that were constructed to be equal in MAU. In Experiment 1, four alternatives were designed in such a way that the choice of each alternative would be consistent with one particular choice strategy, one of which was the CR strategy. In Experiment 2, participants were presented with a CR alternative and a number of arbitrary alternatives. In both experiments, participants tended to choose the CR alternative. The CR alternative was on average evaluated as more attractive than other alternatives. In addition, measures of WED, between given alternatives and the ideal alternative, by and large agreed with the preference order for choices and attractiveness evaluations of the different types of alternatives. These findings indicate that both choices and attractiveness evaluations are guided by proximity of alternatives to an ideal alternative.

Fiedler et al. (2009), reviewed evidence for the utilization of a contingency inference strategy termed pseudocontingencies (PCs). In PCs, the more frequent levels (and, by implication, the less frequent levels) are assumed to be associated. PCs have been obtained using a wide range of task settings and dependent measures. Yet, the readiness with which decision makers rely on PCs is poorly understood. A computer simulation explored two potential sources of subjective validity of PCs. First, PCs are shown to perform above chance level when the task is to infer the sign of moderate to strong population contingencies from a sample of observations. Second, contingency inferences based on PCs and inferences based on cell frequencies are shown to partially agree across samples. Intriguingly, this criterion and convergent validity are by-products of random sampling error, highlighting the inductive nature of contingency inferences.

Magical beliefs about contagion via contact (Rozin, Nemeroff, Wane, & Sherrod, 1989) may emerge when people overgeneralize real-world mechanisms of contamination beyond their appropriate boundaries (Lindeman & Aarnio, 2007). Do people similarly overextend knowledge of airborne contamination mechanisms? Previous work has shown that very young children believe merely being close to a contamination source can contaminate an item (Springer & Belk 1994); we asked whether this same hyper-avoidant intuition is also reflected in adults’ judgments. In two studies, we measured adults’ ratings of the desirability of an object that had made contact with a source of contamination, an object nearby that had made no contact with the contaminant, and an object far away that had also made no contact. Adults showed a clear proximity effect, wherein objects near the contamination source were perceived to be less desirable than those far away, even though a separate group of adults unanimously acknowledged that contaminants could not possibly have made contact with either the nearby or far-away object (Study 1). The proximity effect also remained robust when a third group of adults was explicitly told that no contaminating particles had made contact with the objects at any time (Study 2). We discuss implications of our findings for extending the scope of magical contagion effects beyond the contact principle, for understanding the persistence of intuitive theories despite broad acceptance of science-based theories, and for constraining interpretations of the developmental work on proximity beliefs.

Is variety of the spice of life? The present research suggests that the answer depends on the rate of consumption. In three experiments, we find that, whereas a variety of stimuli is preferred to repetition of even a better-liked single stimulus when consumption is continuous, this preference reverses when the satiation associated with repetition is reduced by slowing down the rate of consumption. Decision makers, however, seem to under-appreciate the influence of consumption rate on preference for (and satisfaction with) variety. At high rates of consumption, they correctly anticipate their own, high, desire for variety, but at low rates of consumption people tend to overestimate their own desire for variety. These results complicate the picture presented by prior research on the “diversification bias”, suggesting that people overestimate their own desire for variety only when consumption is spaced out over time.

When faced with a choice, people can normally select no option, i.e., defer choice. Previous research has investigated when and why individuals defer choice, but has almost never looked at these questions when groups of people make choices. Separate reasons predict that groups may be equally likely, more likely, or less likely than individuals to defer choice. We re-analyzed some previously published data and conducted a new experiment to address this question. We found that small groups of people tended to defer choice more often than their members would. Assuming that the groups used a plurality rule but gave additional weight to individual preferences to defer choice allowed the groups’ responses to be predicted quite well. We discuss several possible explanations of these findings.

Individual differences in decision making are a topic of longstanding interest, but often yield inconsistent and contradictory results. After providing an overview of individual difference measures that have commonly been used in judgment and decision-making (JDM) research, we suggest that our understanding of individual difference effects in JDM may be improved by amending our approach to studying them. We propose four recommendations for improving the pursuit of individual differences in JDM research: a more systematic approach; more theory-driven selection of measures; a reduced emphasis on main effects in favor of interactions between individual differences and decision features, situational factors, and other individual differences; and more extensive communication of results (whether significant or null, published or unpublished). As a first step, we offer our database—the Decision Making Individual Differences Inventory (DMIDI; http://html://www.sjdm.org/dmidi), a free, public resource that categorizes and describes the most common individual difference measures used in JDM research.

We conducted three studies to investigate how well pictographs communicate medical screening information to persons with higher and lower numeracy skills. In Study 1, we conducted a 2 (probability level: higher vs. lower) × 2 (reference information: yes vs. no) × 2 (subjective numeracy: higher vs. lower) between-subjects design. Persons with higher numeracy skills were influenced by probability level but not by reference information. Persons with lower numeracy tended to differentiate between a higher and a lower probability when there was no reference information. Study 2 consisted of interviews about the mental processing of pictographs. Higher numeracy was associated with counting the icons and relying on numbers depicted in the graph. Study 3 was an experiment with the same design as in Study 1, but, rather than using reference information, we varied the sequence of task type (counting first vs. non-counting first) to explore the role of the focus on numerical information. Persons with lower numeracy differentiated between higher and lower risk only when they were in the non-counting first condition. Task sequence did not influence the risk perceptions of persons with higher numeracy. In sum, our results suggest that pictographs may be useful for persons with higher and lower numeracy. However, these groups seem to process the graph differently. Persons with higher numeracy rely more on the numerical information depicted in the graph, whereas persons with lower numeracy seem to be confused when they are guided towards these numbers.