Judging the implications of a concession: Conversational distance and belief bias effects

An arguer's position at a given point in an argument can be characterized as a set of commitments. The present study considers the perceptions of ordinary language users about the implications of making a concession for the contents of the conceder's commitment set. In particular, we examine two sources of influence on such lay perceptions—conversational distance (i.e., the number of turns separating the concession from commitments incurred earlier in the argument) and an individual's prior beliefs regarding the content of the argument. Across two studies, college students were administered an argument task assessing the extent to which a concession by the protagonist of an argument on the last move indicated changes to other commitments incurred earlier in the argument. Results indicated that participants were more likely to judge a concession as indicating a change in prior commitments if (a) the commitment was incurred later in the argument than earlier, and (b) the participant disagreed with the protagonists’ thesis in the argument. In addition, performance on deductive reasoning tasks predicted individual differences in the conversational distance effect, but not the belief bias effect.     

Relevance drives attention: Attentional bias for gain- and loss-related stimuli is driven by delayed disengagement

Attentional bias to gain- and loss-related stimuli was investigated in a dot-probe task. We used coloured stimuli that had acquired their valence during the experiment by signalling the chance to either win or lose points in a game task. Replicating previous findings with the additional singleton paradigm, we found attentional bias effects for both gain- and loss-related colours. The effects were due to delayed disengagement from valent stimuli, especially if they were positive, and could not be explained by nonattentional processes like behavioural freezing. Our findings suggest that stimuli signalling opportunities and dangers hold attention, supporting a general motivational relevance principle of the orienting of attention.     

Trait anxiety, defensiveness and selective processing of threat: an investigation using two measures of attentional bias

Attentional biases for threat were examined in a non-clinical sample (N=60), with each participant tested on both the modified Stroop colour-naming and dot probe tasks. Three groups were selected on the basis of trait anxiety and social desirability scale (SDS) scores: “low anxiety” (LA: low trait, low SDS), “repressor” (REP: low trait, high SDS) and “high anxiety” (HA: high trait, low SDS). Results from the colour-naming task suggested that high levels of defensiveness (in combination with low trait anxiety) were associated with greater avoidance of threat. The REP group showed less interference in colour-naming threat than neutral words; whereas the HA group showed increased interference due to threat words. On the dot probe task, there was a general tendency for this non-clinical sample as a whole to show avoidance of social threat relative to neutral words, but there was no bias for physical threat words. Avoidance of social threat was significant only within the REP group. No relationships were found between the measures of cognitive bias from the two tasks, suggesting different underlying mechanisms. Results are discussed in relation to previous findings and theoretical views of the effects of anxiety and defensiveness on the processing of threat.     

Criteria Based Content Analysis: The Less Scientific Road to Truth

Criteria Based Content Analysis (CBCA) is a forensic tool that aims atdistinguishing true from false statements made by crime victims. As such,CBCA and similar techniques are regularly employed by psychologicalexpert-witnesses in court. However, it could be argued that the diagnosticaccuracy of CBCA is moderate, and too low for application in the forensiccontext. The current article discusses problems that arise if conclusionsabout credibility of testimonies based on CBCA are presented in court. Afundamental, yet so far hardly addressed flaw is that CBCA suffers from aninherent truth bias. That is, the underlying notion that credibility isexamined by means of searching for signs supporting truthfulness isscientifically less valid than the approach in which credibility isestablished by focusing on alternative explanations and signs of deceit.     

Are absolute frequencies,relative frequencies,or both effective in reducing cognitive biases?

Biases in probabilistic reasoning are affected by alterations in the presentation of judgment tasks. In our experiments, students made likelihood judgments that an event was produced by various causes. These judgments were made in terms of probability, relative frequency or absolute frequency on a full or a pruned list of causes. When they had little personal experience of the event (causes of death), the pruning bias was smaller with relative frequencies than with absolute frequencies or probabilities. When they had more personal experience of the event (missing a lecture), the bias was less with both types of frequency than with probability but still lowest with relative frequency. We suggest that likelihood information is usually stored as relative frequencies when it has been obtained from public sources but that it is based on event counts when it is derived from personal experience. Copyright © 2000 John Wiley & Sons, Ltd.     

Investigating the roots of the favourite–longshot bias: an analysis of decision making by supply‐ and demand‐side agents in parallel betting markets

This paper offers new insights into the behavioural origins of the ‘favourite–longshot’ bias — an established feature of betting markets, whereby longshots win less often than the subjective probabilities imply and favourites more often. A number of alternative explanations has been offered for this phenomenon but the main debate focuses on whether it is caused by the behaviour of those supplying betting markets (bookmakers) or of the demand‐side agents in these markets (bettors) . This study analyses a new data source which offers detailed information for a large sample of recent UK horseraces on decision‐making behaviour within the parimutuel and the parallel bookmaker‐based betting markets. The results offer strong evidence for the existence of the ‘favourite–longshot’ bias in bookmaker‐based markets, with a corresponding absence of such an effect in the parimutuel case. These results offer support for the view that the origins of the ‘favourite–longshot’ bias lie principally in the decisions of bookmakers rather than in the decisions of bettors. Copyright © 2000 John Wiley & Sons, Ltd.     

Seek and ye shall find: test results are what you hypothesize they are

Expert clinicians were given batteries of psychodiagnostic test results (Rorschach, TAT, Draw-A-Person, Bender-Gestalt, Wechsler) to analyze. For half, a battery came along with a suggestion that the person suffers from Borderline Personality disorder, and for half, that battery was accompanied by a suggestion that he suffers from Paranoid Personality disorder. In Study 1, the suggestion was made indirectly, through a background story that preceded the test results. In Study 2, the suggestion was made directly, by the instructions given. The experts saw in the tests what they hypothesized to be there. In particular, the target diagnoses were rated higher when they were hypothesized than when they were not. Copyright © 1998 John Wiley & Sons, Ltd.     

Notes on the weighting biases in value trees

The variation in the structure of value trees can have undesirable effects on the attribute weights. Earlier experiments suggest that an attribute receives a higher weight if it is presented at an upper level in a value tree or if it is split into subattributes. Here we show that it is flawed to make conclusions about the biases at the individual level based on the averages of weights across large groups of subjects. Averages do not describe individual behavior. Furthermore, the averages of weights tend to approach even weights. By using the data from earlier experiments we illustrate how the averaging can produce different phenomena. We also show that the use of weights based on the rank order of attributes only can easily lead to biases when the structure of a value tree is changed. © 1998 John Wiley & Sons, Ltd.     

Similarity and reluctance to trade

Previous research has shown that after decision makers are endowed with an object, they are reluctant to trade it for an alternative item. This endowment effect can be explained by loss aversion, the tendency to weight losses more heavily than gains. Consequently, there is no reluctance to trade when no true loss is involved. Four studies investigated whether reluctance to trade declines when the trade involves less of a loss—specifically, when one item is traded for another very similar item. Three experiments did not reveal a relation between willingness to trade and the similarity between the two items being traded. A fourth experiment, however, indicated that subjects were quite willing to trade for an identical item, less willing to trade for a similar item, and even less willing to trade for a dissimilar item. Thus, reluctance to trade decreased as the similarity between the endowment and the alternative increased. This result suggests that loss aversion is a function not only of the item being lost but also of the trade itself—that is, of the relation between the two items being traded. © 1998 John Wiley & Sons, Ltd.     

Evidence for a young adult face bias in accuracy and consensus of age estimates

Adults' face processing may be specialized for the dimensions of young adult faces. For example, young and older adults exhibit increased accuracy in normality judgments and greater agreement in attractiveness ratings for young versus older adult faces. The present study was designed to examine whether there is a similar young adult face bias in facial age estimates. In Experiment 1, we created a face age continuum by morphing an averaged young adult face with an averaged older adult face in 5% increments, for a total of 21 faces ranging from 0 to 100% old. Young and older adults estimated facial age for three stimulus age categories [young (morphs 0–30%), middle‐aged (morphs 35–65%), and older adult (morphs 70–100%)]. Both age groups showed the least differentiation in age estimates for young adult faces, despite showing greater consensus across participants in estimates for young faces. In Experiment 2, young and older adults made age estimates for individual young and older adult identities. Both age groups were more accurate and showed greater consensus in age estimates for young faces. Collectively, these results provide evidence for a bias in processing young adult faces beyond that which is often observed in recognition and normality/attractiveness judgment tasks.