Patients suffering from the behavioral variant of Frontotemporal Dementia (FTD-b) often exaggerate their abilities. Are those errors in judgment limited to domains in which patients under-perform, or do FTD-b patients overestimate their abilities in other domains? Is overconfidence in FTD-b patients domain-specific or domain-general? To address this question, we asked patients at early stages of FTD-b to judge their performance in two domains (attention, perception) in which they exhibit relatively spared abilities. In both domains, FTD-b patients overestimated their performance relative to patients with Dementia of Alzheimer Type (DAT) and healthy elderly subjects. Results are consistent with a domain-general deficit in metacognitive judgment. We discuss these findings in relation to “regression to the mean” accounts of overconfidence and the role of emotions in metacognitive judgments.

An experimental test of the descriptive adequacy of the restated diversification principle is presented. The principle postulates that risk-averse utility maximizers will pool risks for their mutual benefit, even if information is missing about the probabilities of losses. It is enough for people to assume that they face equal risks when they pool risks. The results of the experiment support the principle.

It has been proposed that recognition can form the basis of simple but ecologically rational decision strategies (Gigerenzer & Goldstein, 1996). Borges, Goldstein, Ortmann, & Gigerenzer (1999) found that constructing share portfolios based on simple name recognition alone often yielded better returns than the market index. We describe four studies with seven samples of participants from three countries (total N = 319) in which the returns of recognized and unrecognized shares from several stock markets were tracked over various periods of time. We find no support for the claim that a simple strategy of name recognition can be used as a general strategy to select stocks that yield better-than-average returns. However, there was some suggestion in the data that recognition performs better when the market is falling and worse when it is rising. A follow-up study indicated that the absence of an overall recognition effect could not easily be attributed to our reliance on student participants or smaller samples than Borges et al. (1999) had used. We conclude that, with respect to changes in value, selecting stocks on the basis of name recognition is a near-random method of portfolio construction that offers little, if any, benefit to the personal investor.

Economic games involving allocation of resources have been a useful tool for the study of decision making for both psychologists and economists. In two experiments involving a repeated-trials game over twenty opportunities, undergraduates made choices to distribute resources between themselves and an unseen, passive other either optimally (for themselves) but non-competitively, equally but non-optimally, or least optimally but competitively. Surprisingly, whether participants were told that the anonymous other was another student or a computer did not matter. Using such terms as “game” and “player” in the course of the session was associated with an increased frequency of competitive behavior. Males were more optimal than females: a gender-by-incentive interaction was found in the first experiment. In agreement with prior research, participants whose resources were backed by monetary incentive acted the most optimally. Overall, equality was the modal strategy employed, although it is clear that motivational context affects the allocation of resources.

Previous research has identified important determinants of overall evaluations for experiences lived across time. By means of a novel guessing task, I study what decision-makers themselves consider important. As Informants, some participants live and evaluate an experience. As Guessers, others have to infer its overall evaluation by asking Informants questions. I rewarded accurate inferences, and analyzed and classified the questions in four experiments involving auditory, gustatory and viewing experiences. Results show that Guessers thought of overall evaluations as reflecting average momentary impressions. Moreover and alternatively, they tended to consider the personality and attitudes of the experiencing person, experience-specific holistic judgments and behavioral intentions regarding the experience. Thus, according to lay intuitions, overall evaluations are more than a reflection of the experience's momentary impressions.

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.

Many judgment analysis studies employ multiple regression procedures to estimate the importance of cues. Some studies test the significance of regression coefficients in order to decide whether or not specific cues are attended to by the judge or decision maker. This practice is dubious because it ignores type II error. The purposes of this note are (1) to draw attention to this issue, specifically as it appears in studies of self-insight, (2) to illustrate the problem with examples from the judgment literature, and (3) to provide a simple method for calculating post-hoc power in regression analyses in order to facilitate the reporting of type II errors when regression models are used.

We examined how the goal of a decision task influences the perceived positive, negative valence of the alternatives and thereby the likelihood and direction of framing effects. In Study 1 we manipulated the goal to increase, decrease or maintain the commodity in question and found that when the goal of the task was to increase the commodity, a framing effect consistent with those typically observed in the literature was found. When the goal was to decrease, a framing effect opposite to the typical findings was observed whereas when the goal was to maintain, no framing effect was found. When we examined the decisions of the entire population, we did not observe a framing effect. In Study 2, we provided participants with a similar decision task except in this situation the goal was ambiguous, allowing us to observe participants' self-imposed goals and how they influenced choice preferences. The findings from Study 2 demonstrated individual variability in imposed goal and provided a conceptual replication of Study 1.

We propose that people weight fluent, or easy to process, information more heavily than disfluent information when making judgments. Cue fluency was manipulated independent of objective cue validity in three studies, the findings from which support our hypothesis. In Experiment 1, participants weighted a consumer review more heavily when it was written in a clear font than in a less clear font. In Experiment 2, participants placed more weight on information when it was in focus than when it was blurry. In Experiment 3, participants placed more weight on financial information from brokerage firms with easy to pronounce names than those with hard to pronounce names. These studies demonstrate that fluency affects cue weighting independent of objective cue validity.

We report an experiment exploring sequential context effects on strategy choices in one-shot Prisoner’s Dilemma (PD) game. Rapoport and Chammah (1965) have shown that some PDs are cooperative and lead to high cooperation rate, whereas others are uncooperative. Participants played very cooperative and very uncooperative games, against anonymous partners. The order in which these games were played affected their cooperation rate by producing perceptual contrast, which appeared only between the trials, but not between two separate sequences of games. These findings suggest that people may not have stable perceptions of absolute cooperativeness. Instead, they judge the cooperativeness of each fresh game only in relation to the previous game. The observed effects suggest that the principles underlying judgments about highly abstract magnitudes such as cooperativeness may be similar to principles governing the perception of sensory magnitudes.

This study was designed to assess sex-related differences in the selection of an appropriate strategy when facing novelty. A simple visuo-spatial task was used to investigate exploratory behavior as a specific response to novelty. The exploration task was followed by a visual discrimination task, and the responses were analyzed using signal detection theory.

During exploration women selected a local searching strategy in which the metric distance between what is already known and what is unknown was reduced, whereas men adopted a global strategy based on an approximately uniform distribution of choices. Women’s exploratory behavior gives rise to a notion of a secure base warranting a sense of safety while men’s behavior does not appear to be influenced by risk. This sex-related difference was interpreted as a difference in beliefs concerning the likelihood of uncertain events influencing risk evaluation.

Previous research on anchoring has shown this heuristic to be a very robust psychological phenomenon ubiquitous across many domains of human judgment and decision-making. Despite the prevalence of anchoring effects, researchers have only recently begun to investigate the underlying factors responsible for how and in what ways a person is susceptible to them. This paper examines how one such factor, the Big-Five personality trait of openness-to-experience, influences the effect of previously presented anchors on participants' judgments. Our findings indicate that participants high in openness-to-experience were significantly more influenced by anchoring cues relative to participants low in this trait. These findings were consistent across two different types of anchoring tasks providing convergent evidence for our hypothesis.

This paper reports two experiments comparing variants of multiple explanation applied in the early stages of a judgment task (a case involving employee theft) where participants are not given a menu of response options. Because prior research has focused on situations where response options are provided to judges, we identify relevant dependent variables that an intervention might affect when such options are not given. We use these variables to build a causal model of intervention that illustrates both the intended effects of multiple explanation and some potentially competing processes that it may trigger. Although multiple explanation clearly conveys some benefits (e.g., willingness to delay action to engage in information search, increased detail, quality and confidence in alternative explanations) in the present experiments, we also found evidence that it may initiate or enhance processes that attenuate its advantages (e.g., feelings that one does not need more data if one has multiple good explanations).

Ambiguity aversion has been widely observed in individuals’ judgments. Using scenarios that are typical in decision analysis, we investigate ambiguity aversion for pairs of individuals. We examine risky and cautious shifts from individuals’ original judgments to their judgments when they are paired up in dyads.

In our experiment the participants were first asked to specify individually their willingness-to-pay for six monetary gambles. They were then paired at random into dyads, and were asked to specify their willingness-to-pay amount for the same gambles. The dyad’s willingness-to-pay amount was to be shared equally by the two individuals. Of the six gambles in our experiment, one involved no ambiguity and the remaining five involved different degrees of ambiguity. We found that dyads exhibited risk aversion as well as ambiguity aversion. The majority of the dyads exhibited a cautious shift in the face of ambiguity, stating a smaller willingness-to-pay than the two individuals’ average. Our study thus confirms the persistence of ambiguity aversion in a group setting and demonstrates the predominance of cautious shifts for dyads.

We compare experts’ judgments of the appropriateness of a treatment (interferon treatment for melanoma) on the basis of important attributes of this disease (thickness, ulceration, lymph node involvement and type of metastases) to a decision analytic model in which the probabilities of deterioration are derived from the medical literature and from epidemiological studies. The comparison is based on what we call the linearity test, which examines whether appropriateness judgments are a linear function of the epidemiological value of p2, the probability of deterioration of the patient condition if he would have received the treatment. This comparison allows for the assessment of the validity of the experts’ judgments under the assumption that the decision analytic model is valid, or alternatively, the assessment of the validity of the decision analytic model under the assumption that the experts’ judgments are valid. Under the former assumption the results indicate that appropriateness judgments are by and large accurate. Under the latter assumption the results support the idea of a constant treatment effect, the idea that efficacy of a treatment is constant over various levels of severity of the disease. Our results also support the idea that experts’ aggregate judgments far exceed individuals’ judgments.