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1.
Using PISA and PIAAC data from twelve OECD countries, we examine the gap in cognitive skills among immigrants and natives and evaluate how those differences have evolved over time. We also consider how demographics, family background and school quality explain the development of cognitive skills of young people with immigrant backgrounds. The results show, first, that some convergence in skills occurs between second-generation immigrants and natives over time. Second, demographics, family background and school quality variables all contribute to the achievement gaps across different groups. 相似文献
2.
该文认为,《"阅读·探究·体验"手册》是学生阅读的助手,设计时考虑到整体构建章节与整本书阅读相结合。同时,明确主线,整本书阅读的探究要围绕主线展开,在构建手册时,明确整本书阅读探究的核心要点。在开发《"阅读·探究·体验"手册》时,充分考虑到语文学科的核心素养,通过编制手册,提升学生的语文核心素养。 相似文献
3.
Edgardo Ferretti Leticia Cagnina Viviana Paiz Sebastián Delle Donne Rodrigo Zacagnini Marcelo Errecalde 《Information processing & management》2018,54(6):1169-1181
In this work, we present the first quality flaw prediction study for articles containing the two most frequent verifiability flaws in Spanish Wikipedia: articles which do not cite any references or sources at all (denominated Unreferenced) and articles that need additional citations for verification (so-called Refimprove). Based on the underlying characteristics of each flaw, different state-of-the-art approaches were evaluated. For articles not citing any references, a well-established rule-based approach was evaluated and interesting findings show that some of them suffer from Refimprove flaw instead. Likewise, for articles that need additional citations for verification, the well-known PU learning and one-class classification approaches were evaluated. Besides, new methods were compared and a new feature was also proposed to model this latter flaw. The results showed that new methods such as under-bagged decision trees with sum or majority voting rules, biased-SVM, and centroid-based balanced SVM, perform best in comparison with the ones previously published. 相似文献
4.
[目的/意义]研究方法在学术研究中发挥着至关重要的作用。确认图书馆情报学领域主要的研究方法,并对它们进行了解熟悉,以在开展研究时能合理选择、灵活使用,确保研究质量。[方法/过程]对近2 000篇图书馆情报学领域的研究文献以及相关研究方法论文进行内容分析,在此基础上对研究方法的类分命名、图书馆情报学界主要的研究方法的确定、特点和使用注意事项进行介绍和讨论。[结果/结论]研究方法应以数据收集法而不是数据分析法命名。图书馆情报学领域常用的研究方法包括实验法、问卷法、理论研讨法、内容分析法、访谈法和书目计量法,每种方法都有各自的特点。因而在选择使用时,既应根据具体研究课题及研究方法之特性,也要考虑使用注意事项,并尽量在同一研究中采用两种或更多的方法,以扬长避短,更有效地展开研究。 相似文献
5.
This study enhances the existing literature on online trust by integrating the consumers’ product evaluations model and technology adoption model in e-commerce environments. In this study, we investigate how perceived value influences the perceptions of online trust among online buyers and their willingness to repurchase from the same website. This study proposes a research model that compares the relative importance of perceived value and online trust to perceived usefulness in influencing consumers’ repurchase intention. The proposed model is tested using data collected from online consumers of e-commerce. The findings show that although trust and e-commerce adoption components are critical in influencing repurchase intention, product evaluation factors are also important in determining repurchase intention. Perceived quality is influenced by the perceptions of competitive price and website reputation, which in turn influences perceived value; and perceived value, website reputation, and perceived risk influence online trust, which in turn influence repurchase intention. The findings also indicate that the effect of perceived usefulness on repurchase intention is not significant whereas perceived value and online trust are the major determinants of repurchase intention. Major theoretical contributions and practical implications are discussed. 相似文献
6.
Surabhi Verma Som Sekhar Bhattacharyya Saurav Kumar 《Information processing & management》2018,54(5):791-806
Research on the adoption of systems for big data analytics has drawn enormous attention in Information Systems research. This study extends big data analytics adoption research by examining the effects of system characteristics on the attitude of managers towards the usage of big data analytics systems. A research model has been proposed in this study based on an extensive review of literature pertaining to the Technology Acceptance Model, with further validation by a survey of 150 big data analytics users. Results of this survey confirm that characteristics of the big data analytics system have significant direct and indirect effects on belief in the benefits of big data analytics systems and perceived usefulness, attitude and adoption. Moreover, there are mediation effects that exist among the system characteristics, benefits of big data analytics systems, perceived usefulness and the attitude towards using big data analytics system. This study expands the existing body of knowledge on the adoption of big data analytics systems, and benefits big data analytics providers and vendors while helping in the formulation of their business models. 相似文献
7.
目的:振动训练是一种新兴的的训练方式,现阶段已经得到了较为广泛的应用。本文主要通过对现有振动训练研究进行总结概括,旨在探讨振动训练对运动员身体素质的影响。方法:主要采用文献资料法,通过知网、万方、维普等中文期刊数据库检索查阅前人实验研究文献,并对其结论进行总结归纳。结论:通过振动训练可以促进肌肉力量的增长以及肌肉爆发力的增长,对力量素质发展有积极的促进作用;振动训练可以有效提高运动员肌肉爆发力,对速度素质发展有促进作用;振动训练可以增强心肺功能以及肌肉耐力水平,可提高运动员的耐力素质;振动训练可以提高肌肉及韧带的伸展性对运动员柔韧素质发展有着较好的影响,有学者认为振动训练对柔韧素质没有影响。 相似文献
8.
粤港澳大湾区以其独特的地理优势,在国家发展大局中具有重要的战略地位。采用问卷调查、深度访谈和中介效应分析等方法,选取广东居民赴香港参加体育赛事者为调查对象,了解两岸居民参与体育赛事受到哪些因素的影响及其影响程度,帮助相关部门企业制定合理策略促进两岸体育爱好者交流及地方经济增长,同时进一步拓展了跨境消费行为研究,特别是跨境体育消费研究。结果显示,赛事产品因素及相关吸引因素对个人态度及行为意愿具有重要影响,而经济因素和交通因素对于跨境体育消费者的决策影响十分有限。通关因素、货币汇率因素对跨境参加体育赛事影响不明显。 相似文献
9.
借鉴ACSI顾客满意度测评指数模型,结合中国群众性马拉松赛事的特点,运用探索性因子分析法建立中国马拉松赛事参赛者满意度测评指标体系,基于此,构建中国马拉松赛事参赛者满意度测评指数模型。研究发现:中国马拉松赛事参赛者满意度测评指数模型的指标包括参赛者期望、硬服务质量感知、软服务质量感知、感知价值、参赛者满意度、参赛者抱怨、参赛者忠诚度7个因素。就各个自变量对中国马拉松赛事参赛者满意度的影响路径来看,参赛者对服务的预期通过对软服务质量感知、硬服务质量感知间接正向影响中国马拉松赛事参赛者满意度;参赛者的服务质量感知既直接又间接地正向影响参赛者的满意度,参赛者的软服务质量感知通过硬服务质量感知和感知价值间接正向影响参赛者的满意度,参赛者的硬服务质量感知通过感知价值间接正向影响参赛者的满意度。就各个自变量对中国马拉松赛事参赛者满意度的影响程度而言,参赛者的软服务质量感知对其满意度影响最大,其次依次为硬服务质量感知、服务期望和感知价值。 相似文献
10.
Qianqian Zhou Tze Ping Loh Tony Badrick Chun Yee Lim 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2021,31(2)
IntroductionIt is unclear what is the best strategy for applying patient-based real-time quality control (PBRTQC) algorithm in the presence of multiple instruments. This simulation study compared the error detection capability of applying PBRTQC algorithms for instruments individually and in combination using serum sodium as an example.Materials and methodsFour sets of random serum sodium measurements were generated with differing means and standard deviations to represent four simulated instruments. Moving median with winsorization was selected as the PBRTQC algorithm. The PBRTQC parameters (block size and control limits) were optimized and applied to the four simulated laboratory data sets individually and in combination.ResultsWhen the PBRTQC algorithm were individually optimized and applied to the data of the individual simulated instruments, it was able to detect bias several folds faster than when they were combined. Similarly, the individually applied algorithms had perfect error detection rates across different magnitudes of bias, whereas the error detection rates of the algorithm applied on the combined data missed smaller biases. The performance of the individually applied PBRTQC algorithm performed more consistently among the simulated instruments compared to when the data were combined.DiscussionWhile combining data from different instruments can increase the data stream and hence, increase the speed of error detection, it may widen the control limits and compromising the probability of error detection. The presence of multiple instruments in the data stream may dilute the effect of the error when it only affects a selected instrument. 相似文献