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51.
Abstract

In this introduction to the issue Semiotic tools in early mathematical knowledge, we offer a theoretical perspective that provides meaning to the different contributions. We begin by reviewing three perspectives bearing an important influence on the study of mathematical development in childhood (the Piagetian, the information processing and the neonativist perspectives). Next, we underscore the need for developmental studies in this domain to consider the semiotic component, and hence the socio-cultural component, in depth. The contributions that form this volume — a theoretical article, five papers and four short reports of empirical studies and a review of an instructional approach — illustrate different ways of including the semiotic component in the study of children’s mathematical knowledge.  相似文献   
52.
Abstract

This paper presents a case study of a first grade student to illustrate the diversity of her understandings related to variables and variable notation. While prior research has documented secondary school students’ difficulties with variables and variable notation, we identify many productive understandings in this much younger student, leading us to question the prevailing argument that students might have difficulties with variables due mostly to their own limitations. We draw our data from a teaching experiment that explored functional relationships. Individual interviews were carried out with a subset of the students in the experiment prior to, as well as mid-way through and at the end of the experiment. This paper focuses on a set of three interviews with one of the first grade students. We illustrate the shifts that occurred in the student’s understandings about variables and variable notation across as well as within each of the three interviews.  相似文献   
53.
    
Two major approaches to deal with randomness or ambiguity involved in mathematical programming problems have been developed. They are stochastic programming approaches and fuzzy programming approaches. In this paper, we focus on multiobjective linear programming problems with random variable coefficients in objective functions and/or constraints. Using chance constrained programming techniques, the stochastic programming problems are transformed into deterministic ones. As a fusion of stochastic approaches and fuzzy ones, after determining the fuzzy goals of the decision maker, interactive fuzzy satisficing methods to derive a satisficing solution for the decision maker by updating the reference membership levels is presented. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
54.
    
A component-functions model of choice behavior is proposed for performance on interdependent concurrent variable-interval (VI) variable-interval schedules based on the product of two component functions, one that enhances behavior and one that reduces behavior. The model is the solution to the symmetrical pair of differential equations describing behavioral changes with respect to two categories of reinforcers: enhancing and reducing, or excitatory and inhibitory. The model describes residence time in interdependent concurrent VI VI schedules constructed from arithmetic and exponential distributions. The model describes the data reported by Alsop and Elliffe (1988) and Elliffe and Alsop (1996) with a variance accounted for of 87% compared to 64% accounted for by the Davison and Hunter (1976) model and 42% by Herrnstein's (1970) hyperbola. The model can explain matching, undermatching, and overmatching in the same subject under different procedures and has the potential to be extended to performance on concurrent schedules with more than two alternatives, multiple schedules, and single schedules. Thus, it can be considered as an alternative to Herrnstein's quantitative law of effect.  相似文献   
55.
    
The purpose of this experiment is to test whether shift flexibility in kindergarten children is a joint function of rule‐usage and inhibition of attention. Sixty‐six children were given either a distraction or facilitation condition in a computerized version of the dimensional change card sort task. In the distraction condition, the background of the post‐shift matching stimulus was inconsistent with the relevant matching dimension. In the facilitation condition, the background of the post‐shift matching stimulus was consistent with the relevant matching dimension. Results revealed that children made few errors in the standard version of the shift task, thereby supporting Cognitive complexity and control theory's contention that 5‐year‐old children shift easily across dimensions due to their use of higher‐order setting rules to solve contradictions. The proportion of errors increased however in the distraction condition suggesting that attention to the background interfered with children's ability to shift between dimensions. Therefore, these data provide evidence that refocusing attention to dimensions along with rule‐use processes affect shift flexibility and argue for the inclusion of both factors into theoretical accounts of shift performance. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
56.
    
Most recent writing linking science and literature has concerned itself with challenges to the epistemological status of scientific knowledge in an attempt to demonstrate its contingency, arguing in the more radical efforts that the structures of science are no more than useful fictions. This essay also includes an epistemological comparison between science and literature, but instead of making grand or meta–statements about the nature of knowing generally in the two fields, mine is a much narrower aim. My exploration entails two tasks. First, I provide a close–up look at a particular type of experiment, called the delayed–choice experiment, which clearly reveals the strangeness of the quantum world. In connection with this experiment, I discuss wave functions—mathematical expressions used by physicists to describe quantum behavior and predict the outcome of experiments involving quanta. Second, I look at Walt Whitman's “Song of Myself” focusing on the meaning of the “self” in the poem. My aim is to treat the object of study in each field as a “text” and to assert and demonstrate a parallel in the strategies of thought and response between physicists (“readers”) pondering the meaning and status of a wave function and poem readers pondering the meaning and status of the poem's self. In Whitman's “Song” we find an attempt to understand complex aspects of human experience that are said to transcend ordinary reality, an effort for which I believe there are parallels in the attempts of modern physicists to understand complex, nonintuitive aspects of the subatomic world. While not making the kind of broad claims eschewed above, I do suggest that this focused study has interesting implications since both the wave function and the poem's self force their respective sets of “readers” to confront questions of ultimacy—to consider, that is, epistemological and ontological issues of more than passing interest to students of science as well as those of metaphysics and theology.  相似文献   
57.
    
Participants were pretrained and tested on mutually entailed trigonometric relations and combinatorially entailed relations as they pertained to positive and negative forms of sine, cosine, secant, and cosecant. Experiment 1 focused on training and testing transformations of these mathematical functions in terms of amplitude and frequency followed by tests of novel relations. Experiment 2 addressed training in accordance with frames of coordination (same as) and frames of opposition (reciprocal of) followed by more tests of novel relations. All assessments of derived and novel formula‐to‐graph relations, including reciprocal functions with diversified amplitude and frequency transformations, indicated that all 4 participants demonstrated substantial improvement in their ability to identify increasingly complex trigonometric formula‐to‐graph relations pertaining to same as and reciprocal of to establish mathematically complex repertoires.  相似文献   
58.
    
The dual pathway to creativity model argues that creativity—the generation of original and appropriate ideas—is a function of cognitive flexibility and cognitive persistence, and that dispositional or situational variables may influence creativity either through their effects on flexibility, on persistence, or both. This model is tested in a number of studies in which participants performed creative ideation tasks. We review work showing that cognitive flexibility, operationalised as the number of content categories surveyed, directly relates to idea originality, but that originality can also be achieved by exploring a few content categories in great depth (i.e., persistence). We also show that a global processing mode is associated with cognitive flexibility, but only leads to high originality in tasks that capitalise on cognitive flexibility. We finally show that activating positive mood states enhance creativity because they stimulate flexibility, while activating negative mood states can enhance creativity because they stimulate persistence. Implications for theory and practice are discussed.  相似文献   
59.
This study examined dispositional and situative antecedents of vigilant and avoidant coping behavior. Seventy-two subjects were classified in coping style on the basis of their responses to the vigilance and cognitive avoidance scales of the Mainz Coping Inventory (MCI, Krohne, 1989), and alternatively, on their trait anxiety and defensiveness scores (cf. Weinberger, Schwartz, & Davidson, 1979). In a subsequent laboratory task, subjects were exposed to various conditions of predictability of an aversive event. In anticipation of an aversive loud tone, coping behavior was operationally defined as choosing to listen either to a warning channel (i.e., vigilance) or instead to music (i.e., avoidance). Probability of occurrence of a warning signal while listening to the warning channel varied across trials, being either 0%, 33%, 66%, or 100%. Subjects were exposed to each level and were informed about the respective probability in advance. In general, listening to the warning channel increased with an increase in the probability of the warning signal. However, four groups of subjects who differed in their pattern of coping behavior across trials were observed: rigid-avoidant copers (always listening to music), rigid-vigilant copers (always monitoring the warning channel), flexible copers (switching from music to warning channel with increasing probability of warning), and inconsistent copers (vacillating between music and warning channel regardless of probability of warning). Coping style classifications did not show substantial associations with coping behavior. However, subjects demonstrating the inconsistent coping pattern scored high on trait anxiety.  相似文献   
60.
积极情绪对视觉注意的调节及其机制   总被引:1,自引:0,他引:1       下载免费PDF全文
在积极心理学思潮的推动下, 已有研究不但发现积极情绪扩展了空间和时间注意范围、增加了注意灵活性, 而且发现在积极情绪下个体对积极刺激表现出了注意偏向。对这些现象, 先前研究主要以积极情绪的扩展与建构理论、情绪信息等价说等理论来加以解释。但这些理论主要从宏观上强调情绪信息对注意加工的启动或积极情绪对注意资源分布的调节, 并不能清楚地揭示积极情绪对注意调节的内在机制。神经生化机制研究发现, 这些现象可能与多巴胺系统对注意控制能力的调节以及积极情绪对初级视觉皮层编码的调节有关。将来研究者可以基于不同的种类的注意选择和注意模型来进一步拓展积极情绪对注意调节的研究, 同时注重对其机制的探讨和理论的整合与创新。  相似文献   
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