The anchoring bias reflects rational use of cognitive resources

Cognitive biases, such as the anchoring bias, pose a serious challenge to rational accounts of human cognition. We investigate whether rational theories can meet this challenge by taking into account the mind’s bounded cognitive resources. We asked what reasoning under uncertainty would look like if people made rational use of their finite time and limited cognitive resources. To answer this question, we applied a mathematical theory of bounded rationality to the problem of numerical estimation. Our analysis led to a rational process model that can be interpreted in terms of anchoring-and-adjustment. This model provided a unifying explanation for ten anchoring phenomena including the differential effect of accuracy motivation on the bias towards provided versus self-generated anchors. Our results illustrate the potential of resource-rational analysis to provide formal theories that can unify a wide range of empirical results and reconcile the impressive capacities of the human mind with its apparently irrational cognitive biases.     

Questioning Pygmalion in the twenty-first century: the formation,transmission, and attributional influence of teacher expectancies

Teacher expectancy effects, the class of phenomena in which teacher beliefs about students influence student outcomes, are widely believed to operate through recursive processes of teacher-student interaction. Recent work in “wise” interventions has shown profound and robust effects in educational domains, and has attributed these effects to similar recursive processes (Yeager and Walton 2011). In this paper, we lay a foundation for forging connections between what we know about expectancy effects and how we might envision applying that knowledge as a lever in intervention research. We review the evidence for the existence and significance of teacher expectancy effects, as well as their possible mediators, including perceptual biases, confirmation biases, stereotyping, and attributional biases. We also hypothesize that empathy could play a role in mediating a relationship between expectancies and attributions. Finally, we propose a research agenda focused on the transmission, mediation, and attributional effects of teacher expectancies.     

Cueing listeners to attend to a target talker progressively improves word report as the duration of the cue-target interval lengthens to 2,000 ms

Endogenous attention is typically studied by presenting instructive cues in advance of a target stimulus array. For endogenous visual attention, task performance improves as the duration of the cue-target interval increases up to 800 ms. Less is known about how endogenous auditory attention unfolds over time or the mechanisms by which an instructive cue presented in advance of an auditory array improves performance. The current experiment used five cue-target intervals (0, 250, 500, 1,000, and 2,000 ms) to compare four hypotheses for how preparatory attention develops over time in a multi-talker listening task. Young adults were cued to attend to a target talker who spoke in a mixture of three talkers. Visual cues indicated the target talker’s spatial location or their gender. Participants directed attention to location and gender simultaneously (“objects”) at all cue-target intervals. Participants were consistently faster and more accurate at reporting words spoken by the target talker when the cue-target interval was 2,000 ms than 0 ms. In addition, the latency of correct responses progressively shortened as the duration of the cue-target interval increased from 0 to 2,000 ms. These findings suggest that the mechanisms involved in preparatory auditory attention develop gradually over time, taking at least 2,000 ms to reach optimal configuration, yet providing cumulative improvements in speech intelligibility as the duration of the cue-target interval increases from 0 to 2,000 ms. These results demonstrate an improvement in performance for cue-target intervals longer than those that have been reported previously in the visual or auditory modalities.     

High-magnetic-field-induced formation of aligned equiaxed grains during directional solidification

The application of a high magnetic field is capable of inducing the formation of aligned equiaxed grains in alloys during directional solidification. The alignment and refinement of the grains is enhanced as the magnetic field intensity increases. The thermoelectric power difference at the liquid/solid interface in four alloys has been measured in situ during directional solidification and it is concluded that the formation of aligned equiaxed grains in a magnetic field should be attributed to the combined action of a thermoelectric magnetic force and a magnetization force.     

An ecological study of professors' memory for student names and faces: A replication and extension

Abstract

This experiment measured university professors' memory for the names and faces of current and former students over a two-semester span. If courses function as contextual retrieval cues for professors to remember their students, the passing of each semester should diminish the distinctiveness of these cues. Based on the Bruce and Young (1986) model of face recognition, we hypothesised that as contextual cues become less distinctive, performance should suffer more on name recall tests than on name or face recognition tests. We found that name free recall and portrait-cued name recall declined very sharply after one semester (6 months), and face recognition declined after two semesters (12 months), whereas name recognition remained perfect These results provide a general replication and extension of Bahrick (1984), and show that difficulties in recalling names cannot be due to any weakening of name representations in memory. We suggest that name recall may be dependent on contextual cues that become less distinctive with succeeding semesters.     

Pitch discrimination without awareness in congenital amusia: Evidence from event-related potentials

Congenital amusia is a lifelong disorder characterized by a difficulty in perceiving and producing music despite normal intelligence and hearing. Behavioral data have indicated that it originates from a deficit in fine-grained pitch discrimination, and is expressed by the absence of a P3b event-related brain response for pitch differences smaller than a semitone and a bigger N2b–P3b brain response for large pitch differences as compared to controls. However, it is still unclear why the amusic brain overreacts to large pitch changes. Furthermore, another electrophysiological study indicates that the amusic brain can respond to changes in melodies as small as a quarter-tone, without awareness, by exhibiting a normal mismatch negativity (MMN) brain response. Here, we re-examine the event-related N2b–P3b components with the aim to clarify the cause of the larger amplitude observed by Peretz, Brattico, and Tervaniemi (2005), by experimentally matching the number of deviants presented to the controls according to the number of deviants detected by amusics. We also re-examine the MMN component as well as the N1 in an acoustical context to investigate further the pitch discrimination deficit underlying congenital amusia. In two separate conditions, namely ignore and attend, we measured the MMN, the N1, the N2b and the P3b to tones that deviated by an eight of a tone (25 cents) or whole tone (200 cents) from a repeated standard tone. The results show a normal MMN, a seemingly normal N1, a normal P3b for the 200 cents pitch deviance, and no P3b for the small 25 cents pitch differences in amusics. These results indicate that the amusic brain responds to small pitch differences at a pre-attentive level of perception, but is unable to detect consciously those same pitch deviances at a later attentive level. The results are consistent with previous MRI and fMRI studies indicating that the auditory cortex of amusic individuals is functioning normally.     

How Do Consumers Transfer Existing Knowledge? A Comparison of Analogy and Categorization Effects

The trend in recent consumer research has been to emphasize the similarities between analogy and categorization. In this investigation, we merge the literature on analogy, categorization, and structure mapping theory to reach a better understanding of their differences. In 3 experiments, we compare consumers’ responses to analogy and categorization cues and find that analogy places much greater constraints on knowledge transfer than categorization by focusing consumers on relational similarities. Illustrating this, the analogy group in Study 1 was just as likely as the categorization group to generate relational inferences, but much less likely to generate attribute inferences. Likewise, the results of Study 2 indicate that the analogy group restricted their processing of features lying outside the common relational system, leading to inferior recall relative to the categorization group. Building on these findings, Study 3 demonstrates that, under certain circumstances, analogy and categorization work together syn‐ergistically to enhance consumer memory.