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91.
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The authors clarify the source of a conflict between previous findings related to metacognitive control over the distribution of practice. In a study by L. Son (2004), learners were initially presented pairs of Graduate Record Examination (GRE) vocabulary words and their common synonyms for 1 s, after which they chose to study the pair again immediately (massed practice), later (spaced practice), or not at all (done). Learners chose spaced practice less as pair difficulty increased. A. S. Benjamin and R. D. Bird (2006), using different materials and procedures and a longer presentation duration (5 s), concluded just the opposite. The authors adopted Son’s materials and procedures and replicated her findings with a 1-s stimulus duration. However, the declining choice of spacing as item difficulty increased largely reflected learners’ failure to fully perceive items with brief presentations. With longer presentations, ensuring full perception, the choice of spaced practice increased with greater pair difficulty, in agreement with Benjamin and Bird. Theoretical implications are discussed in the context of discrepancy-reduction and proximal-learning perspectives. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
93.
In the late 1980s, J. W. Fantuzzo and colleagues conducted a review of the self-management literature in order to better define the characteristics of this class of interventions. Results indicated that many interventions were minimally student-directed despite the title “self-managed” and that student-managed interventions demonstrated incremental effects above teacher-managed interventions. In the current study, updated information was compiled with regard to how self-management interventions have been described, including the degree to which self-management interventions continue to rely on external (i.e., teacher) contingencies. Review of the literature identified 16 different characterizations of self-management interventions, each of which varied widely in terms of the number of intervention components included as well as the degree to which students were involved in implementation. Although self-observation and recording of a predefined behavior appear to be the cornerstones of self-management interventions, meaningful differences were noted, including whether reinforcement was involved and whether changes in performance were tracked over time. Furthermore, although self-management interventions appear to have undergone a small shift toward increased reliance on internal (i.e., student-managed) contingencies, adults continue to play a large role in the implementation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
94.
Evolutionary invasion analysis is a powerful technique for modelling in evolutionary biology. The general approach is to derive an expression for the growth rate of a mutant allele encoding some novel phenotype, and then to use this expression to predict long-term evolutionary outcomes. Mathematically, such ‘invasion fitness’ expressions are most often derived using standard linear stability analyses from dynamical systems theory. Interestingly, there is a mathematically equivalent approach to such stability analyses that is often employed in mathematical epidemiology, and that is based on so-called ‘next-generation’ matrices. Although this next-generation matrix approach has sometimes also been used in evolutionary invasion analyses, it is not yet common in this area despite the fact that it can sometimes greatly simplify calculations. The aim of this article is to bring the approach to a wider evolutionary audience in two ways. First, we review the next-generation matrix approach and provide a novel, and easily intuited, interpretation of how this approach relates to more standard techniques. Second, we illustrate next-generation methods in evolutionary invasion analysis through a series of informative examples. Although focusing primarily on evolutionary invasion analysis, we provide several insights that apply to biological modelling in general.  相似文献   
95.
To what extent do graduate students in clinical psychology complete assigned readings? A total of 744 graduate students in American Psychological Association-accredited doctoral programs completed an online survey regarding reading in graduate school (67% response rate, of those viewing the survey). The reported amount of assigned reading varied widely, with an average of 330 pages per week. Compliance ratings suggested that about half the assigned reading is completed thoroughly and that thorough reading is more common than skimming or not reading assigned material. Motivating and hindering factors for reading are reported, and implications for faculty are considered. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Even though the research on supplier selection is abundant, the works usually only consider the critical success factors in the buyer–supplier relationship. However, the negative aspects of the buyer–supplier relationship must also be considered simultaneously. The main objective in this study is to propose an analytical approach to select suppliers under a fuzzy environment. A fuzzy analytic hierarchy process (FAHP) model, which incorporates the benefits, opportunities, costs and risks (BOCR) concept, is constructed to evaluate various aspects of suppliers. Multiple factors that are positively or negatively affecting the success of the relationship are analyzed by taking into account experts’ opinion on their importance, and a performance ranking of the suppliers is obtained. TFT-LCD manufacturers in Taiwan, which is the largest TFT-LCD producer country in the world, are facing increasing competition nowadays, and the selection of the most appropriate suppliers for cooperation is essential for firms to achieve competitive advantage. A case study of backlight unit supplier selection for a TFT-LCD manufacturer is presented, and the proposed model is applied to facilitate the decision process. The model is a general form that can be tailored and applied by firms that are making decisions on supplier selection.  相似文献   
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Most apocalyptic films are considered dystopian based on their aesthetic terms, yet many of their narratives are structured in such a way to reveal our society's larger utopian desires—particularly in terms of our future relationship with nature, the role of the individual in society, and particular ideals of community life. This article traces several dominant themes found within this genre of cinema as related to contemporary urban design solutions and recent post-disaster strategies, in order to expose what collectively we may be hoping for, as well as still fear.  相似文献   
100.
This paper presents United States energy portfolios for the year 2030, developed from seven different Perspectives. The Perspectives are characterized by different weights placed on fourteen defining values (e.g., cost, social acceptance). The portfolios were constructed to achieve three primary goals, energy independence, energy security, and greenhouse gas reductions. The portfolios are also evaluated over a comprehensive set of secondary criteria (e.g., economic growth, technical feasibility). It is found that very different portfolios based on very different defining values can achieve the three primary goals. Commonalities among the portfolios include reliance upon cellulosic ethanol, nuclear power, and energy efficiency to meet year 2030 energy demands. It is concluded that the US energy portfolio must be diverse and to achieve national energy goals will require an explicit statement of goals, a strong role for government, and coordinated action across society.  相似文献   
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