Recent research has emphasized emotion’s role in non-utilitarian judgments, but has not focused much on characteristics of subjects contributing to those judgments. The present article relates utilitarian judgment to individual disposition to experience various emotions. Study 1 first investigated the relationship among state emotions and utilitarian judgment. Diverse emotions were elicited during judgment: guilt, sadness, disgust, empathy, anger, and anxiety, etc. Using psychological scales, Study 2 found that trait emotions predict the extent of utilitarian judgments, especially trait anger, trait disgust, and trait empathy. Unlike previous research that designated emotions only as factors mitigating utilitarian judgment, this research shows that trait anger correlates positively with utilitarian judgment. On the other hand, disgust and empathy correlated negatively. Guilt and shame—though previous research argued that their absence increased utilitarian judgment—appear unrelated to the extent of utilitarian judgment. These results suggest that people’s emotional dispositions can affect their judgment. This finding might contribute to untangling the complex mechanisms of utilitarian judgments.

Would you redirect a trolley to save five people even if it means that the trolley will run over a person on the side track? Most people say they would. Would you push that same person into the path of the trolley in order to save the five? Most people say they would not. These sorts of intuitive moral judgments are made rapidly and seem almost automatic. Now imagine a combined choice context where one can redirect a trolley, push a person in its path or do nothing. The number of lives lost from intervening can be varied. The most straightforward interpretations of current theories of moral judgment predict either no effect or that the combined context will lead to greater focus on lives lost. In contrast, we observe a similarity effect such that utilitarian choice may become less attractive in the combined choice context.

Slowing climate change will almost certainly require a reduction in greenhouse gas emissions, but agreement on who should reduce emissions by how much is difficult, in part because of the self-serving bias—the tendency to believe that what is beneficial to oneself is also fair. Conducting surveys among college students in the United States and China, we show that each of these groups displays a nationalistic self-serving bias in judgments of a fair distribution of economic burdens resulting from mitigation. Yet, we also show, by disguising the problem and the identity of the parties, that it is possible to elicit perceptions of fairness that are not influenced by national interests. Our research reveals that the self-serving bias plays a major role in the difficulty of obtaining agreement on how to implement emissions reductions. That is, the disagreement over what constitutes fair climate policy does not appear to be due to cross-national differences in what constitutes a fair distribution of burdens. Interventions to mitigate the self-serving bias may facilitate agreement.

Whereas much literature exists on “choice overload”, less is known about effects of numbers of alternatives in donation decisions. We hypothesize that donations increase with the number of recipients, albeit at a decreasing rate, and reflect donors’ knowledge of the recipients. Donations involve different concepts of fairness—equity and equality—and these can interact with numbers of alternatives. In two experiments, respondents indicated how they would donate lottery winnings of 50 Euros. Results showed, first, that more was donated to non-governmental organizations and campaigns that respondents knew better. Second, total donations increased with the number of recipients albeit at a decreasing rate. Third, when limited to giving to only one of multiple alternatives, donors gave less than when this restriction did not apply. Fourth, variability of donations can both increase and decrease with the number of potential recipients. We comment on theoretical and practical implications as well as suggesting issues for future research.

Excess choice has previously been shown to have detrimental effects on decisions about consumer products. As the number of options increases, people are more likely to put off making an active choice (i.e., defer) and show less satisfaction with any purchase actually made. We extend this line of enquiry to choosing a charitable organisation to volunteer for. The issue is important because the number of voluntary organisations is enormous and the impact of such a decision may be greater than for consumer decisions in terms of time commitment and benefits to the volunteer and society. Study 1 asked students to examine a real volunteering website and record how many organisations they considered, decision difficulty and whether or not they would like to sign up for a chosen organisation or prefer to defer a decision. Study 2 presented either a relatively small (10) or large (30) choice set of hypothetical organisations and measured deferment likelihood and decision difficulty. In both studies the more options considered, the greater the likelihood to defer. This effect was mediated by decision difficulty. This research is the first to find that detrimental effects of excess choice extend to volunteering. Implications for volunteer recruitment are discussed.

Donation requests often convey numerical information about the people in need. In two studies we investigated the effects of numeracy and presentation format on the underlying affective and cognitive mechanisms of donation decisions. In Study 1, participants were presented with information about a victim in need, either in a frequency format or in a percentage format. In Study 2, we manipulated the identifiability and number of target victims. Our results demonstrate that donations of individuals lower in numeracy were more susceptible to changes in numeric presentation format than those higher in numeracy. Importantly, the underlying mechanisms for donations differed by numeracy. Whereas the mental image of the victim influenced donation decisions of less numerate people only, the estimated impact of a donation was positively correlated with donation amounts for both more and less numerate individuals.

We used a diffusion model to examine the effects of response-bias manipulations on response time (RT) and accuracy data collected in two experiments involving a two-choice decision making task. We asked 18 subjects to respond “low” or “high” to the number of asterisks in a 10×10 grid, based on an experimenter-determined decision cutoff. In the model, evidence is accumulated until either a “low” or “high” decision criterion is reached, and this, in turn, initiates a response. We performed two experiments with four experimental conditions. In conditions 1 and 2, the decision cutoff between low and high judgments was fixed at 50. In condition 1, we manipulated the frequency with which low- and high-stimuli were presented. In condition 2, we used payoff structures that mimicked the frequency manipulation. We found that manipulating stimulus frequency resulted in a larger effect on RT and accuracy than did manipulating payoff structure. In the model, we found that manipulating stimulus frequency produced greater changes in the starting point of the evidence accumulation process than did manipulating payoff structure. In conditions 3 and 4, we set the decision cutoff at 40, 50, or 60 (Experiment 1) and at 45 or 55 (Experiment 2). In condition 3, there was an equal number of low- and high-stimuli, whereas in condition 4 there were unequal proportions of low- and high-stimuli. The model analyses showed that starting-point changes accounted for biases produced by changes in stimulus proportions, whereas evidence biases accounted for changes in the decision cutoff.

The tempting fate effect is that the probability of a fateful outcome is deemed higher following an action that “tempts” the outcome than in the absence of such an action. In this paper we evaluate the hypothesis that the effect is due to an illusion of control induced by a causal framing of the situation. Causal frames require that the action make a difference to an outcome and that the action precedes the outcome. If an illusion of control modulates the reluctance to tempt fate, then actions that make a difference to well-being and that occur prior to the outcome should tempt fate most strongly. In Experiments 1–3 we varied whether the action makes a difference and the temporal order of action and outcome. In Experiment 4 we tested whether an action can tempt fate if all outcomes are negative. The results of all four experiments supported our hypothesis that the tempting fate effect depends on a causal construal that gives rise to a false sense of control.

According to recent dual-process theories, interpersonal trust is influenced by both impulsive and deliberative processes. The present research explores the determinants of deliberative trust, investigating how trust decisions are affected by the availability of cognitive resources. We test the interaction of two relevant factors: self-control (the ability to exert mental control over one’s behavior) and the default response (a preselected option that requires minimal or no effort). Past research has shown that self-control has extensive effects on social behavior and decision making. Here, we report that the effect of self-control on trust depends on the default. Across two studies, we find no direct link between self-control and trust. Instead, self-control affects trust indirectly by influencing the level of effort in decision making. Poor self-control (due to experimental depletion or trait-based differences) predicts adherence to the default—the response that requires the least effort.