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161.
Risk taking is highly prevalent among adolescent males, and a range of studies have shown that decisions become riskier if a peer is present. However, previous studies have typically provided participants with explicit probabilities of risk in each situation. This does not accurately reflect adolescents' real‐world risk taking, where decisions are made in ambiguous situations alongside their peers. Aiming for a more ecologically valid design, the present experiment manipulated situational ambiguity and examined its interplay with group decision making and developmental factors. Adolescent males (N = 202) aged 12–15 completed a “Wheel of Fortune” task and then self‐reported their score, presenting an opportunity to cheat as a measure of antisocial risk taking. As predicted, adolescents were more likely to take risks when probabilities were ambiguous rather than explicit. Further, higher levels of gambling choices were made by groups in ambiguous, but not risk situations. Age significantly predicted gambling in ambiguous conditions, whereas developmental dispositions (risk perception, reward sensitivity, and inhibitory control) did not play a role. Findings provide an insight into the social and situational conditions under which adolescent males engage in reckless behavior.  相似文献   
162.
The first 1,000 days of life are a critical window of vulnerability to exposure to socioeconomic and health challenges (i.e. poverty/undernutrition). The Brain Imaging for Global Health (BRIGHT) project has been established to deliver longitudinal measures of brain development from 0 to 24 months in UK and Gambian infants and to assess the impact of early adversity. Here results from the Habituation‐Novelty Detection (HaND) functional near‐infrared spectroscopy (fNIRS) task at 5 and 8 months are presented (N = 62 UK; N = 115 Gambia). In the UK cohort distinct patterns of habituation and recovery of response to novelty are seen, becoming more robust from 5 to 8 months of age. In The Gambia, an attenuated habituation response is evident: a larger number of trials are required before the response sufficiently suppresses relative to the response during the first presented trials. Furthermore, recovery of response to novelty is not evident at 5 or 8 months of age. As this longitudinal study continues in The Gambia, the parallel collection of socioeconomic, caregiving, health and nutrition data will allow us to stratify how individual trajectories of habituation and recovery of response to novelty associate with different risk factors and adaptive mechanisms in greater depth. Given the increasing interest in the use of neuroimaging methods within global neurocognitive developmental studies, this study provides a novel cross‐culturally appropriate paradigm for the study of brain responses associated with attention and learning mechanisms across early development.  相似文献   
163.
This paper describes a teaching methodology whereby students can gain practical experience of ethical decision-making in the engineering design process. We first argue for the necessity to teach a 'practical' understanding of ethical issues in engineering education along with the usual theoretical or hypothetical approaches. We then show how this practical understanding can be achieved by using a collaborative design game, describing how, for example, the concept of responsibility can be explored from this practical basis. We conclude that the use of games in design education can provide an excellent basis for discussing practical and ethical reasoning during the process of design.  相似文献   
164.
A form (or pattern) of inference, let us say, explicitlysubsumes just such particular inferences as are instances of the form, and implicitly subsumes thoseinferences with a premiss and conclusion logically equivalent to the premiss and conclusion of an instanceof the form in question. (For simplicity we restrict attention to one-premiss inferences.) A form ofinference is archetypal if it implicitly subsumes every correct inference. A precise definition (Section 1)of these concepts relativizes them to logics, since different logics classify different inferences ascorrect, as well as ruling differently on the matter of logical equivalence which entered into the definitionof implicit subsumption. When relativized to classical propositional logic, we find (Section 2) thatall but a handful of `degenerate' inference forms turn out to be archetypal, whereas matters are verydifferent in this respect for the case of intuitionistic propositional logic (Sections 3 and 4), and an interestingstructure emerges in this case (the poset of equivalence classes of inference forms, with respect tothe equivalence relation of implicitly subsuming the same inferences). Thus a more accurate, if excessivelylong-winded title would be 'Archetypal and Non-Archetypal Forms of Inference in Classical andIntuitionistic Propositional Logic'. Some left-overs are postponed for a final discussion (Section 5).The overall intention is to introduce a new subject matter rather than to have the last word on thequestions it raises; indeed several significant questions are left as open problems.  相似文献   
165.
We offer a view on how probability is related to logic. Specifically, we argue against the widely held belief that standard classical logics have no direct way of modelling the certainty of assumptions in theories and no direct way of stating the certainty of theorems proved from these (uncertain) assumptions. The argument rests on the observation that probability densities, being functions, can be represented and reasoned with naturally and directly in (classical) higher-order logic.  相似文献   
166.
The logic of judging relative mass from a two-body collision is developed from data presented by Runeson and Vedeler (1993). Data from two experiments are analyzed on a point-by-point basis, and strong support for the theory that mass-ratio judgments are mediated by separate speed and angle heuristics is shown. This analysis is accomplished by reducing the collision event to two elementary features: the presence of ricochet and the ratio of exit speeds. The heuristics that both ricochet and greater exit speed specify relative lightness are shown to explain the basic patterns of data presented by Runeson and Vedeler.  相似文献   
167.
Gender and Mathematical Problem Solving   总被引:1,自引:0,他引:1  
Duffy  Jim  Gunther  Georg  Walters  Lloyd 《Sex roles》1997,37(7-8):477-494
The relationship between gender and mathematical problem-solving among high ability students depends on the attributes of the problem solving questions. This was evident in the present study of 12-year-olds. The children were from predominately White families. Eighty-three males and 76 females were tested in both the fall and the spring on the Fennema-Sherman Mathematics Attitudes Scales and on the Canadian Test of Basic Skills (CTBS). In the Spring, students were also tested on the GAUSS. Both the CTBS and the GAUSS measure mathematical problem solving. Among high ability students, there were gender differences on the problem-solving scale of the CTBS but not on the GAUSS, even though the GAUSS was independently rated as the more abstract and difficult of the two tests. The present study describes the implications of this for the question of the origin of gender differences in mathematics, and also looked at the relationship between attitudes toward mathematics and mathematical problem-solving performance.  相似文献   
168.
When spatial ability was regressed on a measure of general intelligence in a large national sample of 12th-graders, there was a distinct downturn in the regression line at about -2 SD units. A bimodal distribution of spatial ability was found among these low scoring students, suggesting 2 qualitatively different types of individuals. Relative to students of expected spatial ability, those below expected in spatial ability were high on verbal skills and low on performance skills. Students unexpectedly low in spatial ability performed relatively well on cognitive tests that required answering unambiguous questions by retrieving information directly from long term memory, whereas they performed relatively poorly on tests requiring inference and perception of relations among novel stimuli. Students unexpectedly low in spatial ability performed especially poorly at tests involving visual-spatial perception skills. Results were similar for both sexes. The relatively poor performance of those unexpectedly low in spatial ability does not appear to be related to health problems, personality, interest differences, or biographical data. An organic impairment possibly related to lateralization represents a reasonable causal hypothesis for these data.  相似文献   
169.
A scale designed to tap adherence to the Protestant work ethic ideology in Australia has been developed. The development of the Australian Work Ethic scale (AWE) was based on items selected on the basis of factor analysis and item-total correlations. Validation of the scale found that it has convergent and concurrent validity. Specifically, it correlated highly with both the Mirels and Garrett (1971) Protestant work ethic scale and Blood's (1969) pro-Protestant ethic scale. It was also found that people who strongly endorsed the work ethic ideology as measured on the AWE scale, tended to stress internal causal explanations for unemployment, and were less willing to provide assistance to the unemployed, findings which are in line with the work ethic ideology. The findings were discussed in terms of the continued efficacy of the work ethic ideology in Australia. Possible uses of this new measure in future research are suggested.  相似文献   
170.
The coding system described was originally devised to facilitate the analysis of mother-infant interaction. Our aims were to provide accurate measures of the duration of different activities, to enable identification of particular actions in order to carry out sequential analyses, and to allow systematic assessment and improvement of reliability. At the time recording began, there appeared to be no readily available systems which achieved all of these aims. The system described here enables coded videotape material to be examined with the assistance of a computer. This is implemented through two subsystems, those of record and playback. In the playback subsystem the behaviour units identified by a coder are mapped on to this record. This results in a protocol of behaviour on a highly accurate time base.  相似文献   
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