Combining advice: the weight of a dissenting opinion in the consensus

We present two studies that evaluate how people combine advice and how they respond to outlying opinions. In a preliminary study, we found that individuals use discounting strategies when they encounter an extreme opinion in a small sample of opinions taken only once (a one‐shot advice‐taking situation). The main study examines the influence of outlying opinions (which may or may not be accurate) within a learning paradigm with feedback. This study shows that it is easy to reinforce a discounting strategy (with feedback) whereas it is more difficult to counteract this default strategy. In the discussion we consider cognitive, statistical, and strategic justifications for discounting opinions, from both theoretical and practical points of view. Copyright © 2004 John Wiley & Sons, Ltd.     

Inclusive and exclusive modes of thinking: Studies of prediction, preference, and social perception during parliamentary elections

The 1999 Israeli multi-party parliamentary election was used for studying the effects of inclusive and exclusive modes of thinking. In three experiments, we tested a theoretical framework whose major elements are the justification process, a distinction between middling and clearcut options, and the use of inclusion and exclusion threshold criteria. In Studies 1-2, respondents were asked to predict either of which parties would win seats in the parliament (inclusion) or which parties would fail to win seats in the parliament (exclusion). In Study 2, respondents were also asked to use inclusive or exclusive modes to indicate their preferences and in Study 3, they were asked to make either inclusive or exclusive judgments about the platforms of two extreme political parties. We found consistent discrepancies between the outcomes of inclusion and exclusion processes, such that choice sets generated in exclusion were larger than those generated in inclusion. A second major finding was the option effect, namely, the discrepancies between the two modes of thinking were larger for middling than for clearcut options. The third main finding was an expertise effect: the less knowledgeable respondents exhibited greater discrepancies than did the more knowledgeable ones. Our theoretical framework accounts for the inclusion-exclusion discrepancy, the option effect, and the expertise effect. We discuss the implications of these findings for judgment and choice in social settings and also for the understanding of question-form effects in opinion surveys—in particular, the allow-forbid effect.     

The Maximization Paradox: The costs of seeking alternatives

Contrary to the common belief that more options lead to better decisions, recent research has demonstrated that choosing from a large number of options can have detrimental psychological effects. We investigated whether people were willing to sacrifice resources for more options, and whether choice-making orientation moderated such willingness. As predicted, people who were motivated to make the best choice possible—“maximizers”—were more willing to sacrifice resources such as time to attain a larger choice array than were people who tend to search for a satisfactory choice (i.e., “satisficers”). Additionally, maximizers who sacrificed to attain more options were ultimately less satisfied with their choice relative to maximizers who chose from a small assortment, and to satisficers (Studies 2 and 3). We term the pattern in which maximizers tend to sacrifice resources to attain more options that ultimately reduce their satisfaction, the “Maximization Paradox”.     

Inferring accuracy for judges and items: Choice of unit of analysis reverses the conclusions

This study explores the relationship between the precision and the accuracy of forecasts using either judge or item as the unit of analysis. Participants in five experiments answered general-knowledge questions by indicating intervals that were likely to include the correct answer. Results indicate that the precision of an interval estimate is not a straightforward cue to the likelihood that such an interval includes the truth (hit rate). Whereas judges who state more precise estimates (i.e. who provide narrower interval estimates) have lower hit rates, questions for which the average judgment is more precise have higher hit rates. Thus, the relation between precision and accuracy depends on whether one ‘slices’ the data by judge or by question. We offer an explanation for this seemingly paradoxical effect and implement it as a computer simulation to demonstrate its validity. © 1997 John Wiley & Sons, Ltd.     

Precision and accuracy of judgmental estimation

Whereas probabilistic calibration has been a central normative concept of accuracy in previous research on interval estimates, we suggest here that normative approaches for the evaluation of judgmental estimates should consider the communicative interaction between the individuals who produce the judgments and those who receive or use them for making decisions. We analyze precision and error in judgment and consider the role of the accuracy–informativeness trade-off (Yaniv and Foster, 1995) in the communication of estimates. The results shed light on puzzling findings reported earlier in the literature concerning the calibration of subjective confidence intervals. © 1997 John Wiley & Sons, Ltd.     

Follow-up of victims of one terrorist attack in Israel: ASD, PTSD and the perceived threat of Iraqi missile attacks

The first aim of the study was to examine the relationships between acute stress reactions and post-traumatic reactions following exposure to a terrorist attack. The second was to examine whether exposure to a terrorist attack increases the perceived threat and fear of renewed Iraqi missile attacks. Data were collected at two points in time: during the first month after the exposure to a terrorist attack (N = 54), and four months later (N = 44). Twenty-four percent of the exposed group had acute stress disorder (ASD), and a similar percentage had PTSD. Among participants who had ASD, the chances of developing PTSD were three times greater than among those who had never experienced ASD. Among participants who had been exposed to a terrorist attack and developed PTSD, the perceived threat of an Iraqi missile attack was greater than among those who had been exposed to a terrorist attack but did not develop PTSD, or among the participants in the control group. The discussion deals with the findings in light of the current controversy regarding ASD and the current situation in Israel.     

The Production of Self and the Destruction of the Other's Memory and Identity in Israeli/Palestinian Education on the Holocaust/Nakbah

This paper characterizes a present institutionalizedunwillingness of both the Israeli and Palestinian educationalsystems to acknowledge each other's suffering because of the presenceof what the author terms `the otherness of the other.' This isdone largely through hegemonic control of memory of genocidesendured by both and through limiting constructions of the self.Coming to terms with `each other' paves the way for ahumanistic-oriented counter-education, one based in mutualacknowledgment and open dialogue.     

Noninvolvement of testosterone in aggressive defense behavior in the male blind mole rat Spalax ehrenbergi

Blind mole rats (Spalax ehrenbergi) are solitary and aggressive subterranean rodents. Aggressive defense behavior in the mole rat functions to deter neighboring competitors from territory, food, and mates and includes seismic and odor signals. The aim of the present study was to determine whether the aggressive defense behavior displayed by male mole rats is testosterone dependent. Five behavioral variables were taken as being representative of such aggressive interaction: exposing teeth, biting, bulldozing movements of the head, soil blocking, and self‐grooming. We monitored male testosterone levels and aggressiveness throughout the annual cycle, which can be divided into three main climatic periods: cold and rainy (September–February); warm, during which the soil is still moist and easily excavated (March–May); and hot (June–August), when the soil is hard and dry. In a second experiment the effect of endogenous and exogenous testosterone on male aggressive defense behavior was determined before and after castration and following testosterone propionate replacement. We found fluctuations in male testosterone concentrations, with three peaks: in November, May, and August, one in each of the three climatic periods. However, these fluctuations did not correlate with male aggressive behavior, which remained constant throughout the year. Furthermore, because neither castration nor testosterone propionate replacement in castrated individuals affected their defense behavior, we suggest that such behavior in male mole rats is testosterone independent. The continuous excavation and maintenance of the mole rat’s underground tunnel system demands high energy expenditure year‐round and constant defense of territory sites and food caches from intraspecific rivals. Thus, although testosterone may fluctuate as a result of seasonal breeding cycles, constant high levels of aggressive defense throughout the year are crucial for the survival of the male mole rat in its solitary subterranean environment. Aggr. Behav. 27:64–72, 2001. © 2001 Wiley‐Liss, Inc.