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181.
《Journal of applied research in memory and cognition》2014,3(3):171-176
Testing effects have been well-established across a variety of studies involving school-age children. Specifically, children's test performance improves when they are given the opportunity to practice retrieval prior to the final test as compared to when practice involves only study. The current investigation focused on the influence of testing with feedback on fifth graders’ learning of science concepts. Across two experiments, 65 students studied twenty key concept definitions. After study, the definitions were randomly assigned to one of four conditions: control, test only, study only, and test plus feedback. Concepts assigned to the latter three conditions were presented again (either for test only, study only, or test plus feedback) during two separate sessions, and a final test was administered during a separate session. At the final test, students were asked to provide the definition for each of the twenty key concepts. Final test performance was best for definitions that had been tested with feedback, followed by recall for those that had only been tested or only restudied, with lowest performance for those that did not receive additional practice. Despite multiple sessions spaced across several days, however, performance for all conditions was low, which may have resulted from the ineffective use of feedback. In summary, testing followed by feedback can boost younger students learning of science concepts, but mastery will require the use of other strategies as well. 相似文献
182.
Observers viewed modified launching effect displays containing a spatial gap between the final location of the launcher (a black square) and the initial location of the target (a black outline square with a white interior). In some conditions, a set of stationary objects (black outline squares with white interiors) filled the spatial gap, and these objects began changing colour upon contact from the launcher. The colour changes could involve all gap objects turning black, the first gap object turning dark grey and subsequent gap objects turning successively lighter grey, or first gap object turning light grey and subsequent gap objects turning successively darker grey. The colour changes could move from the launcher to the target or from the target to the launcher. The gap objects could also remain unchanged. Participants rated whether the launcher caused subsequent motion of the target and how much force the launcher imparted to the target. The sequence of colour changes, and the sequence of locations in which colour changes occurred, influenced ratings; sequences of colour changes consistent with the idea that influence of the launcher was transmitted across gap objects to the target resulted in higher ratings. Implications for visual perception of causality are discussed. 相似文献
183.
A portfolio forecasting model based on particle swarm optimization (PSO) algorithm with automatic factor scaling is proposed in this Article to effectively improve the accuracy of related analysis model in portfolio application. Firstly, the portfolio problem is analyzed and a hybrid constraint portfolio model is obtained by improving portfolio model with consideration of general portfolio model and combination of market value constraint and upper bound constraint according to Markowitz's theory. Secondly, PSO algorithm is introduced during analysis on portfolio model and solution is found with the hybrid constraint portfolio model of PSO on portfolio. In addition, in order to further improve the performance of PSO in model solution, automatic factor scaling is used for adaptive learning on parameters associated with PSO, to improve convergence of the algorithm. At last, simulation experiments show that the algorithm proposed can obtain a more ideal investment portfolio scheme, thereby reducing investment risks and obtaining greater investment returns. 相似文献
184.
Lisa Fullam 《Theology & Science》2018,16(3):319-329
It is fruitless to attempt to genetically engineer virtuous living. Prenatal genome modification could, in principle, establish desired traits and predispose us to certain behaviors. But, traits given at birth are not the same thing as a virtuous character that can be acquired only by self-discipline. The ethicist further fears that free market eugenics—the sale of gene modification—may become one more expression of the social sin our culture inherits. 相似文献
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采用地震后建筑物倒塌,被困人员转运的任务情景,以99名消防指挥系大四学员为被试,研究个体情境意识和团队情境意识的关系,以及社会网络关系中的网络密度和结构洞指标在其中的调节作用。结果表明:(1)个体情境意识与团队情境意识不相关,即团队情境意识不是个体情境意识的简单相加;(2)共享情境意识对团队情境意识有负向影响:个体情境意识之间的差异越大,团队情境意识就越高;(3)对于网络密度较大的团队,结构洞对共享情境意识和团队情境意识的关系起到正向调节的作用;(4)对于网络密度较小的团队,结构洞对共享情境意识和团队情境意识的关系起到负向调节的作用。 相似文献