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191.
The search for different options before making a consequential choice is a central aspect of many important decisions, such as mate selection or purchasing a house. Despite its importance, surprisingly little is known about how search and choice are affected by the observed and objective properties of the decision problem. Here, we analyze the effects of two key properties in a binary choice task: the options' observed and objective values, and the variability of payoffs. First, in a large public data set of a binary choice task, we investigate how the observed value and variability relate to decision‐makers' efforts and preferences during search. Furthermore, we test how these properties influence the chance of correctly identifying the objectively maximizing option, and how they affect choice. Second, we designed a novel experiment to systematically analyze the role of the objective difference between the options. We find that a larger objective difference between options increases the chance for correctly identifying the maximizing option, but it does not affect behavior during search and choice. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
192.
Two important and related developments in children between 18 and 24 months of age are the rapid expansion of object name vocabularies and the emergence of an ability to recognize objects from sparse representations of their geometric shapes. In the same period, children also begin to show a preference for planar views (i.e., views of objects held perpendicular to the line of sight) of objects they manually explore. Are children's emerging view preferences somehow related to contemporary changes in object name vocabulary and object perception? Children aged 18 to 24 months old explored richly detailed toy objects while wearing a head camera that recorded their object views. Both children's vocabulary size and their success in recognizing sparse three-dimensional representations of the geometric shapes of objects were significantly related to their spontaneous choice of planar views of those objects during exploration. The results suggest important interdependencies among developmental changes in perception, action, word learning, and categorization in very young children.  相似文献   
193.
Crime linkage and the investigation of behavioural consistency amongst serial offenders has been a flourishing field of research over the past decade or so, especially with respect to serial sex offenders. The emerging research in this field has often portrayed serial sex offenders as a single, distinct, and homogeneous group. Such an assumption, however, has never been empirically examined. Using a criminal career approach and a sample of 72 serial sex offenders who have committed a total of 361 sexual assaults on stranger victims, the current study aims to examine and describe subgroups of crime series patterns amongst serial sex offenders in terms of duration and frequency of offending. The level of environmental consistency display (i.e. offender's choice of crime location and characteristics of the crime site selected) across subgroups of crime series patterns is also examined. Study findings suggest the presence and heterogeneity of crime series patterns amongst serial sex offenders, advocating for the consideration of subgroups of crime series patterns when studying serial sex offenders. Moreover, the offenders' level of environmental consistency varies across the different crime series patterns identified, allowing for the identification of subgroups of offenders showing a higher or lower level of environmental consistency. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
194.
Background. Students’ perceptions of classroom goals influence their adoption of personal goals. To assess different forms of classroom goals, recent studies have favoured an overall measure of performance classroom goals, compared to a two‐dimensional assessment of performance‐approach and performance‐avoidance classroom goals (PAVCG). Aims. This paper considered the relationship between students’ perceptions of classroom goals and their endorsement of personal achievement goals. We proposed that three (instead of only two) classroom goals need to be distinguished. We aimed to provide evidence for this hypothesis by confirmatory factor analysis (CFA) and also by divergent associations between the respective classroom goal and students’ personal goal endorsement. Sample. A total of 871 (474 female) 10th grade students from several German high schools participated in this study. Method. Students responded to items assessing their perception of mastery, performance‐approach, and performance‐avoidance goals in the classroom. Additionally, the students reported how much they personally pursue mastery, performance‐approach, and performance‐avoidance goals. All items referred to German as a specific school subject. Results. A CFA yielded empirical support for the proposed distinction of three (instead of only two) different kinds of classroom goals. Moreover, in hierarchical linear modelling (HLM) analyses all three classroom goals showed unique associations with students’ personal goal adoption. Conclusions. The findings emphasized the need to distinguish performance‐approach and PAVCG. Furthermore, our results suggest that multiple classroom goals have interactive effects on students’ personal achievement strivings.  相似文献   
195.
Several positive functions have been ascribed to integrative internal dialogues (IDs), which are based on mutual openness to a partner's viewpoint and a readiness to consider his/her arguments in order to potentially modify one's own stance. As the technique of imagined intergroup contact (IIC) favorably influences attitudes towards outgroup members, it was hypothesized that IIC would have a beneficial impact on IDs with an outgroup member when the dialogue is focused on differences between ingroup and outgroup. In the experiment, 151 people (80 women) participated. It revealed that after IIC, both the dialogue author's confrontational attitude and the interlocutor's integrative attitude decreased. Thus, IIC made participants less inclined to gain an advantage over their imagined outgroup interlocutors and more inclined to give them freedom in IDs. However, the effect was significant only when the author's involvement in ID was high or medium.  相似文献   
196.
The purpose of the present study was to investigate the relationship between brand names and consumers' perceived risk. Hypotheses dealt with whether the presence of a product's brand name affects consumers' perceived risk towards shopping online; whether the familiarity with a brand name influences consumers' perceived risk; and whether online shoppers and non‐shoppers perceive risk towards shopping online differently. Results indicate that the presence or absence of a product's brand name affects online shoppers' perceived risk, but in the opposite direction to that expected. There was no significant difference between online shoppers' perceived risk vis‐à‐vis brand familiarity; however, online shoppers possessed lower perceived risk than non‐shoppers. Implications and limitations are discussed and recommendations for future research are provided. Copyright © 2004 Henry Stewart Publications Ltd.  相似文献   
197.
The dual systems model of adolescent risk‐taking portrays the period as one characterized by a combination of heightened sensation seeking and still‐maturing self‐regulation, but most tests of this model have been conducted in the United States or Western Europe. In the present study, these propositions are tested in an international sample of more than 5000 individuals between ages 10 and 30 years from 11 countries in Africa, Asia, Europe and the Americas, using a multi‐method test battery that includes both self‐report and performance‐based measures of both constructs. Consistent with the dual systems model, sensation seeking increased between preadolescence and late adolescence, peaked at age 19, and declined thereafter, whereas self‐regulation increased steadily from preadolescence into young adulthood, reaching a plateau between ages 23 and 26. Although there were some variations in the magnitude of the observed age trends, the developmental patterns were largely similar across countries.  相似文献   
198.
Verb learning is difficult for children (Gentner, 1982 ), partially because children have a bias to associate a novel verb not only with the action it represents, but also with the object on which it is learned (Kersten & Smith, 2002 ). Here we investigate how well 4‐ and 5‐year‐old children (N = 48) generalize novel verbs for actions on objects after doing or seeing the action (e.g., twisting a knob on an object) or after doing or seeing a gesture for the action (e.g., twisting in the air near an object). We find not only that children generalize more effectively through gesture experience, but also that this ability to generalize persists after a 24‐hour delay.  相似文献   
199.
To harness the complexity of their high‐dimensional bodies during sensorimotor development, infants are guided by patterns of freezing and freeing of degrees of freedom. For instance, when learning to reach, infants free the degrees of freedom in their arm proximodistally, that is, from joints that are closer to the body to those that are more distant. Here, we formulate and study computationally the hypothesis that such patterns can emerge spontaneously as the result of a family of stochastic optimization processes, without an innate encoding of a maturational schedule. In particular, we present simulated experiments with an arm where a computational learner progressively acquires reaching skills through adaptive exploration, and we show that a proximodistal organization appears spontaneously, which we denote PDFF (Proximo Distal Freezing and Freeing of degrees of freedom). We also compare this emergent organization between different arm morphologies—from human‐like to quite unnatural ones—to study the effect of different kinematic structures on the emergence of PDFF.  相似文献   
200.
Previous studies have shown that adults who stutter produce smaller corrective motor responses to compensate for unexpected auditory perturbations in comparison to adults who do not stutter, suggesting that stuttering may be associated with deficits in integration of auditory feedback for online speech monitoring. In this study, we examined whether stuttering is also associated with deficiencies in integrating and using discrepancies between expected and received auditory feedback to adaptively update motor programs for accurate speech production. Using a sensorimotor adaptation paradigm, we measured adaptive speech responses to auditory formant frequency perturbations in adults and children who stutter and their matched nonstuttering controls. We found that the magnitude of the speech adaptive response for children who stutter did not differ from that of fluent children. However, the adaptation magnitude of adults who stutter in response to auditory perturbation was significantly smaller than the adaptation magnitude of adults who do not stutter. Together these results indicate that stuttering is associated with deficits in integrating discrepancies between predicted and received auditory feedback to calibrate the speech production system in adults but not children. This auditory‐motor integration deficit thus appears to be a compensatory effect that develops over years of stuttering.  相似文献   
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