我国5种医药大学学报在国内外数据库中高被引论文的对比分析

【目的】 对比国内高被引论文在国外的被引情况与国外高被引论文在国内的被引情况,探讨二者的相关性,以了解国内外高被引论文的差异。【方法】 选择2017年《中国科技期刊引证报告(核心版)》医药大学学报类综合评价总分排名前5位的期刊,选取2008—2017年各期刊在CNKI中的高被引论文共512篇及WoS中高被引论文共486篇,统计分析所选文献的被引频次等相关指标。【结果】 5种期刊的CNKI高被引论文的被引频次差异较小,而WoS高被引论文的被引频次差异较大;CNKI高被引论文的被引频次远高于WoS高被引论文的被引频次;除《南方医科大学学报》外,CNKI/WoS高被引论文的被引频次与其在WoS/CNKI中的被引频次的差异不具有统计学意义(P>0.05)。【结论】 我国5种国内学术影响力较高的医药大学学报的国际影响力均较低,这些期刊国内/外高被引论文的被引频次与其在国外/内的被引频次之间的相关性均不明显,国内外对5种期刊的引用存在差异。     

How far the apple falls from the tree: Intergenerational transmission of educational attainment in Indonesia

We use five waves of the Indonesian Family Life Survey (IFLS) to create unique father-son matched data of the male population (aged 25–53). Using this data, we investigate the evolution of intergenerational transmission of educational attainment in Indonesia over time, by ethnicities (six major ethnic groups), and by regions (twelve provinces). To estimate the persistence in education (measured as schooling years of the father as a predictor of schooling years of the son), we use coefficient of correlation and regression coefficient methods. Our results from the regression coefficient suggest that persistence in Indonesia is declined over time. Whereas, the results from the coefficient of correlation reveals no secular trend in education persistence over time. Thus, to understand the reason behind the secular trend in the correlation coefficient we decompose the correlation following Checchi and García-Peñalosa (2008). The decomposed intergenerational correlation shows that although the persistence is declined at the lower-end of fathers’ education distribution, it is increased at the top-end of the distribution. Therefore, we argue that the coefficient of correlation should be used with caution while analyzing the education policy particularly the persistence in education. Thereafter, we document the stationary distribution and find the conclusive evidence of non-convergence in educational attainment over time among both, ethnicities and regions.     

On teaching about the coefficient of variation in introductory statistics courses

The standard deviation is related to the mean by virtue of the coefficient of variation. Teachers of statistics courses can make use of that fact to make the standard deviation more comprehensible for statistics students.     

Using video to promote early childhood teachers' thinking and reflection

This article examines findings from a qualitative study employing group stimulated-recall interviews using video-recordings of early childhood teachers to elicit their thinking and reflections about their teaching interactions. It focuses on the value of video to enable teachers to reflect on their practices and the extent to which collectively viewing recorded episodes allows negotiated understandings of their own and other teachers' practices. Whilst these findings suggest that video and collective dialogue are useful professional learning tools for teachers to examine and improve their teaching, structural and relational challenges exist that may impact on how effectively such tools are used.     

论集体林权制度改革中的公平与效率

分析集体林权制度改革中不完善引发的种种矛盾对公平与效率的影响,提出完善集体林权制度,推进公平与效率实现的前提和对策:在确立农民经营林业的主体地位的平等,保证农民基本生活的前提下,追求林业土地生产效率;加强系统性地深化推进林业产权改革,加快对产权的界定、流转,保障产权利益的实现。     

A comparative analysis of multi-output frontier models

Recently, there have been more debates on the methods of measuring efficiency. The main objective of this paper is to make a sensitivity analysis for different frontier models and compare the results obtained from the different methods of estimating multi-output frontier for a specific application. The methods include stochastic distance function frontier, stochastic ray frontier, and data envelopment analysis. The stochastic frontier regressions with and without the inefficiency effects model are also compared and tested. The results indicate that there are significant correlations between the results obtained from the alternative estimation methods.     

一类亚纯函数系数的高阶齐次线性微分方程解的性质

在J．K．Langley给出的高阶齐次线性微分方程复振荡的结果的基础上,考虑具有控制系数和系数仅有有限个极点的高阶线性齐次微分方程,研究亚纯系数齐次线性微分方程亚纯解的零点收敛指数,得到了这类方程的线性无关超越解的最少个数和零点收敛指数为有穷的解的最多个数。     

基于RCMLM模型的数学试卷性别DIF研究

RCMLM模型是基于Rasch测量理论的通用拓展模型。利用RCMLM模型对一份普通高中数学试卷进行不同性别的DIF分析。结果表明:该模型可对具有二分计分和多分计分的试题同时进行DIF分析,避免了以往分别对两种计分方式试题进行DIF分析的弊端,保持了试卷的完整性,使DIF分析结果更加有效。     

素数的又一判别法

著名的定理:(ⅰ)P是素数的充分必要条件为。 (ⅱ)P是素数的充分必要条件为。 本文又给出一个判别素数方法:P是素数的充分必要件条为,这里是一个奇数,且。到目前为止,这是较好的判别方法。     

基于基尼系数的耕地质量差异程度分析——以广东省南方稻田耕地地力结果为例

本文提出了利用耕地基尼系数定量评价区域耕地质量差异的方法和其理论依据。以广东省南方稻田耕地地力评价结果为例，结合其他指标对研究区域的耕地质量空间差异进行了实证分析，并根据耕地基尼系数值利用SPSS软件聚类分析模块将研究区域的稻田耕地质量分为4级以显示各市水稻田质量差异程度，然后文章提出耕地洛伦茨曲线的优化，最后文章对广东省南方稻田耕地质量差异实证分析进行总结，并对耕地基尼系数的相对性和变化幅度的微小性进行了讨论。研究结果表明运用耕地基尼系数对区域耕地质量差异进行定量评价的方法简单快捷，为区域耕地质量差异程度的研究提供了一种新思路，对全面区域耕地质量状况和消除耕地质量差异程度宏观政策全面提高耕地质量具有一定的研究意义。