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21.
The Common Core State Standards in Mathematics (CCSSM, 2010) are organized around two types of standards: the standards for mathematical content and standards for mathematical practice. The central goal of this paper is to present cognitive and instructional analyses of standards for mathematical practice through a discussion of field-based activities with inservice secondary mathematics teachers and students. A potential value of the study is that it provides researchers with specific field-based hypotheses on advancing standards for mathematical practice. 相似文献
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The number of trials that is required by an algorithm to produce a given fraction of the problem solutions with a specified level of confidence is analyzed. The analysis indicates that the number of trials required to find a large fraction of the solutions rapidly decreases as the number of solutions obtained on each trial by an algorithm increases. In applications where multiple solutions are sought, this decrease in the number of trials could potentially offset the additional computational cost of algorithms that produce multiple solutions on a single trial. The analysis framework presented is used to compare the efficiency of a homotopy algorithm to that of a Newton method by measuring both the number of trials and the number of calculations required to obtain a specified fraction of the solutions. 相似文献
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We analyze an infinitely repeated version of the Downsian model of elections. The folk theorem suggests that a wide range
of policy paths can be supported by subgame perfect equilibria when parties and voters are sufficiently patient. We go beyond
this result by imposing several suitable refinements and by giving separate weak conditions on the patience of voters and
the patience of parties under which every policy path can be supported. On the other hand, we show that only majority undominated
policy paths can be supported in equilibrium for arbitrarily low voter discount factors: if the core is empty, the generic
case in multiple dimensions, then voter impatience leads us back to the problem of non-existence of equilibrium. We extend
this result to give conditions under which core equivalence holds for a non-trivial range of voter and party discount factors,
providing a game-theoretic version of the Median Voter Theorem in a model of repeated Downsian elections.
J. Duggan was supported by the National Science Foundation, grant number 0213738, is gratefully acknowledged. 相似文献
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化学课程是制药工程专业的必修课程,教学中存在部分理论内容交叉重叠、实验课程相互独立、内容多学时少、教学模式与教学评价体系陈旧等问题。介绍了临沂大学制药工程专业在化学课程改革方面的一些探索与实践,包括对理论课程体系和实验课程体系进行整合和优化、开设化学综合性实验和创新性实验、改进教学方法和进行创新课堂建设、推进化学课程考试和考核改革等,以期为制药工程专业化学课程教学改革提供一些思路和借鉴。 相似文献
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针对一线教师的课例研究成果难以分享和传播的困境,分析了当前课例论文写作中存在的问题:缺乏教学目标、重教学设计而轻教学实践、教学反思不足、文献查阅不够、教学理论与教学实践脱节等。提出了提升课例论文质量的写作框架和内容要求,其容易被一线教师接受,注重继承性和发展性,强调教学实践数据的呈现,强调可复制性和可操作性。 相似文献
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