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21.
We evaluate author impact indicators and ranking algorithms on two publication databases using large test data sets of well-established researchers. The test data consists of (1) ACM fellowship and (2) various life-time achievement awards. We also evaluate different approaches of dividing credit of papers among co-authors and analyse the impact of self-citations. Furthermore, we evaluate different graph normalisation approaches for when PageRank is computed on author citation graphs.We find that PageRank outperforms citation counts in identifying well-established researchers. This holds true when PageRank is computed on author citation graphs but also when PageRank is computed on paper graphs and paper scores are divided among co-authors. In general, the best results are obtained when co-authors receive an equal share of a paper's score, independent of which impact indicator is used to compute paper scores. The results also show that removing author self-citations improves the results of most ranking metrics. Lastly, we find that it is more important to personalise the PageRank algorithm appropriately on the paper level than deciding whether to include or exclude self-citations. However, on the author level, we find that author graph normalisation is more important than personalisation. 相似文献
22.
Zhigang Hu Wencan Tian Shenmeng Xu Chunbo Zhang Xianwen Wang 《Journal of Informetrics》2018,12(4):1133-1145
InCites Essential Science Indicators is becoming increasingly used to identify top-performing research and evaluate the impact of institutes. Unfortunately, our study shows that ESI indicators, as well as other normalized citation indicators, have the following flaws. First, the publication month and the online-to-print delay affect a paper’s probability of becoming a Highly Cited Paper (HCP). Papers published in the earlier months of the year are more likely to accumulate enough citation counts to rank at the top 1% compared with those published in later months of the year. Papers with longer online-to-print delays have an apparent advantage for being selected as HCPs. Research field normalizations lead to the third pitfall. Different research fields have different citation thresholds for HCPs, making research field classification important for a journal. In addition, the uniform thresholds for both articles and reviews in ESI affect the reliability of HCP selection because, on average, reviews tend to have higher citation rates than articles. ESI’s selection of HCPs provides an intuitive feel for the problems of normalized citation impact indicators, such as those provided in InCites and SciVal. 相似文献
23.
Mike Thelwall 《Journal of Informetrics》2018,12(2):430-435
Dimensions is a partly free scholarly database launched by Digital Science in January 2018. Dimensions includes journal articles and citation counts, making it a potential new source of impact data. This article explores the value of Dimensions from an impact assessment perspective with an examination of Food Science research 2008–2018 and a random sample of 10,000 Scopus articles from 2012. The results include high correlations between citation counts from Scopus and Dimensions (0.96 by narrow field in 2012) as well as similar average counts. Almost all Scopus articles with DOIs were found in Dimensions (97% in 2012). Thus, the scholarly database component of Dimensions seems to be a plausible alternative to Scopus and the Web of Science for general citation analyses and for citation data in support of some types of research evaluations. 相似文献
24.
We have studied the efficiency of research in the EU by a percentile-based citation approach that analyzes the distribution of country papers among the world papers. Going up in the citation scale, the frequency of papers from efficient countries increases while the frequency from inefficient countries decreases. In the percentile-based approach, this trend, which is uniform at any citation level, is measured by the ep index that equals the Ptop 1%/Ptop 10% ratio. By using the ep index we demonstrate that EU research on fast-evolving technological topics is less efficient than the world average and that the EU is far from being able to compete with the most advanced countries. The ep index also shows that the USA is well ahead of the EU in both fast- and slow-evolving technologies, which suggests that the advantage of the USA over the EU in innovation is due to low research efficiency in the EU. In accord with some previous studies, our results show that the European Commission’s ongoing claims about the excellence of EU research are based on a wrong diagnosis. The EU must focus its research policy on the improvement of its inefficient research. Otherwise, the future of Europeans is at risk. 相似文献
25.
The study examined current practices in Classical Chinese (CC) reading instruction in Hong Kong and the relationship between different instructional practices and students' strategy use and motivation in CC reading. A total of 519 secondary students voluntarily responded to a questionnaire that measured their perception of CC reading instruction, strategy use, and motivation. The findings indicate while teachers frequently teach both the language and content aspects of CC reading, the teacher-centered approach they are now adopting is ineffective in facilitating students' CC reading development. Relations between different instructional approaches and students’ strategy use and motivation in CC reading are discussed. 相似文献
26.
Adeyinka Tella Olamide Abigail Ibinaiye 《International Information and Library Review》2020,52(1):32-49
AbstractThis study examined staff motivation, satisfaction, and job performance among the librarians and library staff in six selected university libraries in Nigeria. The target population for the study includes the professionals and nonprofessional library staff. A total enumeration sampling technique was used to select 180 respondents, which represent the sample for the study. Data was collected using a self-designed questionnaire titled “Staff Motivation, Satisfaction and Job Performance Questionnaire” (SMSJPQ). Six research questions were developed and answered by the study. The results indicate that librarian and library staff are highly motivated with regular pay while the least motivational factor is frequent interaction with their friends. Library staff are primarily satisfied with their jobs when they are in constant link with their friends. Professional library staff significantly experience better work motivation than their nonprofessional counterparts. Significant correlation exists between staff motivation and job performance and between job satisfaction and job performance. In addition, the two factors (motivation and satisfaction) exert significant contribution to the determinant of librarians and library staff job performance. Based on the findings, the study recommended improvement in the level of motivation of nonprofessionals so that the significant difference with the professional counterpart would not be so much pronounced. 相似文献
27.
28.
In the enthusiastic trend of English learning, an abundance of work is contributing to practical assistance to adult learn-ers in contrast with the paucity of attention on the learners’psychological ba... 相似文献
29.
梁茂成 《徐州师范大学学报(哲学社会科学版)》2004,30(4):66-69
体验主义认为,语言源于人们的生活体验,语言中的词汇通过隐喻的影射作用,获得新的语义。从身体的基本部位之一———"面孔"入手,运用认知语言学理论,结合实证的研究方法,可以证明自然语言中的大部分习语和普通词汇一样,其抽象语义也是通过隐喻的影射作用而获得的;在不同语言的习语中,隐喻在很大程度上具有共性。 相似文献
30.
王昆建 《昆明师范高等专科学校学报》2007,29(1):6-9
儿童作为一个特殊的文学接受群体,呈现着不同于成人的文学接受特点。个体阅读需要、作品吸引力和成人引导是促成儿童主动的或被动的阅读动机。在阅读兴趣选择上儿童表现出明显的渐变性和群体差异性。形象思维是儿童文学接受的主要思维形式。以直接印象介入作品,从故事层面感知而不以理性去判断作品是儿童文学接受中的主要特点。与成人相比,儿童阅读活动还明显带有感性冲动性,即情感性。 相似文献