New: Garbage in, Garbage Out? Some Micro Sources of Macro Errors
Date Posted: Nov 28, 2012
Many institutions, large or small, make their decisions through some process of deliberation. Nonetheless, deliberating institutions often fail, in the sense that they make judgments that are false or that fail to take advantage of the information that their members have. There are four such failures; all of them have implication for large-scale institutions as well as small ones. (1) Sometimes the predeliberation errors of an institution’s members are amplified, not merely propagated, as a re
New: Democracy Under Uncertainty: The ‘Wisdom of Crowds’ and the Free-Rider Problem in Group Decision Mak
Date Posted: Sep 16, 2010
We introduce a game theory model of individual decisions to cooperate by contributing personal resources to group decisions versus by free-riding on the contributions of other members. In contrast to most public-goods games that assume group returns are linear in individual contributions, the present model assumes decreasing marginal group production as a function of aggregate individual contributions. This diminishing marginal returns assumption is more realistic and generates starkly different
New: What’s Next? Judging Sequences of Binary Events
Date Posted: Feb 20, 2010
The authors review research on judgments of random and nonrandom sequences involving binary events with a focus on studies documenting gambler’s fallacy and hot hand beliefs. The domains of judgment include random devices, births, lotteries, sports performances, stock prices, and others. After discussing existing theories of sequence judgments, the authors conclude that in many everyday settings people have naive complex models of the mechanisms they believe generate observed events, and they re
New: Perceived Causality as a Cue to Temporal Distance
Date Posted: Nov 30, 2009
The three experiments reported show that judgments of elapsed time between events depend on perceived causal relations between the events. Participants judged pairs of causally related events to occur closer together in time than pairs of causally unrelated events that were separated by the same actual time interval. The causality-time relationship was first demonstrated for time judgments about historical events. Causally related events
were judged to be significantly closer together in time th
New: Introduction to the Special Issue: Decision Making and the Law
Date Posted: Oct 12, 2009
Legal decision making is different from other types of decision making in several ways. For example, the decision makers range from highly qualified and trained professionals such as judges, making repeated decisions alone to novices such as jurors, making one off decisions in groups. Pertinent information may be unavailable to the decision maker, and he/she is also unlikely to receive much feedback about the quality of a decision. However, legal decision makers rarely suffer any consequences fo
REVISION: Decision and Experience: Why Don't We Choose What Makes Us Happy?
Date Posted: Nov 10, 2008
Recent years have witnessed a growing interest among psychologists and other social scientists in subjective wellbeing and happiness. Here we review selected contributions to this development from the literature on behavioral decision theory. In particular, we examine many, somewhat surprising, findings that show people systematically fail to predict or choose what maximizes their happiness, and we look at reasons why they fail to do so. These findings challenge a fundamental assumption that und
New: Effects of Amount of Information on Judgment Accuracy and Confidence
Date Posted: Nov 10, 2008
When a person evaluates his or her confidence in a judgment, what is the effect of receiving more judgment-relevant information? We report three studies that show when judges receive more information, their confidence increases more than their accuracy, producing substantial confidence-accuracy discrepancies. Our results suggest that judges do not adjust for the cognitive limitations that reduce their ability to use additional information effectively. We place these findings in a more general fr
REVISION: Hedonomics: Bridging Decision Research with Happiness Research
Date Posted: Nov 03, 2008
One way to increase happiness is to increase the objective levels of external outcomes; another is to improve the presentation and choices among external outcomes without increasing their objective levels. Economists focus on the 1st method. We advocate the second, which we call hedonomics. Hedonomics studies (a) relationships between presentations (how a given set of mfoutcomes are arranged among themselves or relative to other outcomes) and happiness and (b) relationships between choice (which
New: Four Failures of Deliberating Groups
Date Posted: Apr 18, 2008
Many groups make their decisions through some process of deliberation, usually with the belief that deliberation will improve judgments and predictions. But deliberating groups often fail, in the sense that they make judgments that are false or that fail to take advantage of the information that their members have. There are four such failures. (1) Sometimes the predeliberation errors of group members are amplified, not merely propagated, as a result of deliberation. (2) Groups may fall victim t
New: Calibration Trumps Confidence as a Basis for Witness Credibility
Date Posted: Apr 09, 2007
In the courtroom and in laboratory studies, confident witnesses are viewed as more credible, and thus have more influence on judgments and verdicts, than unconfident witnesses. In two experiments (with college student subjects) we demonstrate that erroneous testimony may damage the credibility of a high-confidence witness more than a low-confidence one. We show that listeners rely on a source's calibration - whether the source's confidence is appropriate to the level of knowledge - rather than
New: What Happened on Deliberation Day?
Date Posted: Jun 26, 2006
What are the effects of deliberation about political issues? This essay reports the results of a kind of Deliberation Day, involving sixty-three citizens in Colorado. Groups from Boulder, a predominantly liberal city, met and discussed global warming, affirmative action, and civil unions for same-sex couples; groups from Colorado Springs, a predominately conservative city, met to discuss the same issues. The major effect of deliberation was to make group members more extreme than they were when