最优停止规则在多种选择中的应用     

黄平 《赣南师范学院学报》1990,(Z1)

众所周知,在n种物品中选择k种优秀物品是常发生的事。问题是按怎样的选择方式才能使选到的优秀物品的可能性最大。本文应用最优停时定理给出了在n种物品中选择k种物品的一般数学模型及最优选择规则的求解方程;本文还就k等于2给出了最优规则τ_1~α,n及按此规则进行选择所能得到的概率P~2——在n种物品中选择2种优秀物品的最大概率。  相似文献   

Assessing Model Similarity in Structural Equation Modeling     

Keke Lai  Samuel B. Green  Roy Levy  Ray E. Reichenberg  Yuning Xu  Marilyn S. Thompson 《Structural equation modeling》2016,23(4):491-506

Two models can be nonequivalent, but fit very similarly across a wide range of data sets. These near-equivalent models, like equivalent models, should be considered rival explanations for results of a study if they represent plausible explanations for the phenomenon of interest. Prior to conducting a study, researchers should evaluate plausible models that are alternatives to those hypothesized to evaluate whether they are near-equivalent or equivalent and, in so doing, address the adequacy of the study’s methodology. To assess the extent to which alternative models for a study are empirically distinguishable, we propose 5 indexes that quantify the degree of similarity in fit between 2 models across a specified universe of data sets. These indexes compare either the maximum likelihood fit function values or the residual covariance matrices of models. Illustrations are provided to support interpretations of these similarity indexes.  相似文献   

论地方高师院校转型与人才培养模式改革的趋势     

钟锐锋 《绵阳师范学院学报》2003,22(4):22-25

本文分析了当前我国教师教育体系改革和教师专业化发展的形势,并结合基础教育改革的要求,从三个方面阐述了地方高师院校转型和人才培养模式改革的必然趋势.一是地方高师院校办学模式要从“师范教育“向“教师教育“转型,二是地方高师院校要重新建立专业化教师的培养范式,三是高师教育要培养适应基础教育改革要求的、具有综合素质与创新能力的专业化教师.  相似文献   

The skeletons in our closet: E‐learning tools and what happens when one side does not fit all          下载免费PDF全文

Sonya E. Van Nuland  Kem A. Rogers 《Anatomical sciences education》2017,10(6):570-588

In the anatomical sciences, e‐learning tools have become a critical component of teaching anatomy when physical space and cadaveric resources are limited. However, studies that use empirical evidence to compare their efficacy to visual‐kinesthetic learning modalities are scarce. The study examined how a visual‐kinesthetic experience, involving a physical skeleton, impacts learning when compared with virtual manipulation of a simple two‐dimensional (2D) e‐learning tool, A.D.A.M. Interactive Anatomy. Students from The University of Western Ontario, Canada (n = 77) participated in a dual‐task study to: (1) investigate if a dual‐task paradigm is an effective tool for measuring cognitive load across these different learning modalities; and (2) to assess the impact of knowledge recall and spatial ability when using them. Students were assessed using knowledge scores, Stroop task reaction times, and mental rotation test scores. Results demonstrated that the dual‐task paradigm was not an effective tool for measuring cognitive load across different learning modalities with respect to kinesthetic learning. However, our study highlighted that handing physical specimens yielded major, positive impacts on performance that a simple commercial e‐learning tool failed to deliver (P < 0.001). Furthermore, students with low spatial ability were significantly disadvantaged when they studied the bony joint and were tested on contralateral images (P = 0.046, R = 0.326). This suggests that, despite limbs being mirror images, students should be taught the anatomy of, as well as procedures on, both sides of the human body, enhancing the ability of all students, regardless of spatial ability, to take anatomical knowledge into the clinic and perform successfully. Anat Sci Educ 10: 570–588. © 2017 American Association of Anatomists.  相似文献   

Numerical analysis on car-following traffic flow models with delay time     

李莉  施鹏飞 《浙江大学学报(A卷英文版)》2006,7(2):204-209

INTRODUCTION For the past few decades, many researchers have made studies of modelling driver behavior to repro- duce the observed features of traffic flow. Recently Kerner and Rehborn (1997) observed that there are three distinct dynamic phases on highways: free traf- fic flow, coexisting traffic flow and traffic jams. The occurrence of traffic jams without obvious reasons had been explained in terms of the conventional phase transition (Nagatani, 1998). Various traffic flow models, suc…  相似文献   

中学生心理素质教育模式研究     

余万超  刘栋梁  郭淑华  骆成业 《乐山师范学院学报》2004,19(10):104-109

青少年心理问题的发生和表现就其原因既有个体成长、发育过程中的内部矛盾，又有深刻的社会化变迁背景。本针对我国社会转型时期青少年心理问题，探索中学生心理问题的类型及归因，构建中学生心理素质教育的“八大”运行模式。  相似文献   

地脚螺栓埋设方法     

王伦康 《太原大学学报》2006,7(4):82-83

根据螺栓埋设方法与基础混凝土施工方法,可分为直埋与预埋。埋设方法不同,则螺栓支撑方法不同,模具不同。  相似文献   

探析高校人事档案排架法     

陈志宏 《南平师专学报》2008,27(3):97-99

高校的人事部门管理着大量的人事档案,若要充分发挥它们的作用,就必须重视高校人事档案的排架方法。因此,人事档案的具体排架法成为各高校人事档案部门在日常管理中必须认真解决的问题。本文结合高校人事档案的划分状况,简要分析高校人事档案普遍使用的几种排架法,旨在希望各高校的人事档案管理部门能根据本校实际,选择更为科学、合理的排架法。  相似文献   

Constructing a new KS3 curriculum at Brooke Weston CTC: a review and commentary     

Andrew Campbell  Trevor Kerry 《Educational studies》2004,30(4):391-408

This paper reviews changes to the key stage 3 curriculum at a leading comprehensive school. The nature and practical concerns of the changes are described. These move beyond a fresh approach to content; they include issues about engaging students actively in learning for the future, planning around the school's distinctive ethos and expertise in ICT, and using curriculum as a vehicle for providing energy for new staff and heads of department to engage in learning leadership. Theoretical models of curriculum are examined to locate thinking at Brooke Weston CTC in a conceptual framework. The paper suggests that futuristic curriculum development resonates with some classical curriculum models that have been ignored over the past two decades of the National Curriculum.  相似文献   

Time-Varying Effect Sizes for Quadratic Growth Models in Multilevel and Latent Growth Modeling     

Alan Feingold 《Structural equation modeling》2019,26(3):418-429

Multilevel and latent growth modeling analysis (GMA) is often used to compare independent groups in linear random slopes of outcomes over time, particularly in randomized controlled trials. The unstandardized coefficient for the effect of group on the slope from a linear GMA can be transformed into a model-estimated effect size for the group difference at the end of a study. Because effect sizes vary nonlinearly in quadratic GMA, the effect size at the end of a study using quadratic GMA cannot be derived from a single coefficient, and cannot be used to estimate effect sizes at intermediate time points with backward extrapolation. This article formulates equations and associated input commands in Mplus for time-varying effect sizes for quadratic GMA. Illustrative analyses that produced these time-varying effect sizes were presented, and a Monte Carlo study found that bias in the effect sizes and their confidence intervals was ignorable.  相似文献