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1.
We address the question how citation-based bibliometric indicators can best be normalized to ensure fair comparisons between publications from different scientific fields and different years. In a systematic large-scale empirical analysis, we compare a traditional normalization approach based on a field classification system with three source normalization approaches. We pay special attention to the selection of the publications included in the analysis. Publications in national scientific journals, popular scientific magazines, and trade magazines are not included. Unlike earlier studies, we use algorithmically constructed classification systems to evaluate the different normalization approaches. Our analysis shows that a source normalization approach based on the recently introduced idea of fractional citation counting does not perform well. Two other source normalization approaches generally outperform the classification-system-based normalization approach that we study. Our analysis therefore offers considerable support for the use of source-normalized bibliometric indicators.  相似文献   

2.
This paper presents a statistical analysis of the relationship between three science indicators applied in earlier bibliometric studies, namely research leadership based on corresponding authorship, international collaboration using international co-authorship data, and field-normalized citation impact. Indicators at the level of countries are extracted from the SIR database created by SCImago Research Group from publication records indexed for Elsevier’s Scopus. The relationship between authorship and citation-based indicators is found to be complex, as it reflects a country’s phase of scientific development and the coverage policy of the database. Moreover, one should distinguish a genuine leadership effect from a purely statistical effect due to fractional counting. Further analyses at the level of institutions and qualitative validation studies are recommended.  相似文献   

3.
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4.
Field normalized citation rates are well-established indicators for research performance from the broadest aggregation levels such as countries, down to institutes and research teams. When applied to still more specialized publication sets at the level of individual scientists, also a more accurate delimitation is required of the reference domain that provides the expectations to which a performance is compared. This necessity for sharper accuracy challenges standard methodology based on pre-defined subject categories. This paper proposes a way to define a reference domain that is more strongly delimited than in standard methodology, by building it up out of cells of the partition created by the pre-defined subject categories and their intersections. This partition approach can be applied to different existing field normalization variants. The resulting reference domain lies between those generated by standard field normalization and journal normalization. Examples based on fictive and real publication records illustrate how the potential impact on results can exceed or be smaller than the effect of other currently debated normalization variants, depending on the case studied. The proposed Partition-based Field Normalization is expected to offer advantages in particular at the level of individual scientists and other very specific publication records, such as publication output from interdisciplinary research.  相似文献   

5.
Newly introduced bibliometric indices may be biased by the preference of scientists for bibliometric indices, in which their own research receives a high score. To test such a hypothesis, the publication and citation records of nine scientists who recently proposed new bibliometric indices were analyzed in terms of standard indicators, their own indicators, and indicators recently proposed by other scientists. The result of the test was negative, that is, newly introduced bibliometric indices did not favor their authors.  相似文献   

6.
In an age of intensifying scientific collaboration, the counting of papers by multiple authors has become an important methodological issue in scientometric based research evaluation. Especially, how counting methods influence institutional level research evaluation has not been studied in existing literatures. In this study, we selected the top 300 universities in physics in the 2011 HEEACT Ranking as our study subjects. We compared the university rankings generated from four different counting methods (i.e. whole counting, straight counting using first author, straight counting using corresponding author, and fractional counting) to show how paper counts and citation counts and the subsequent university ranks were affected by counting method selection. The counting was based on the 1988–2008 physics papers records indexed in ISI WoS. We also observed how paper and citation counts were inflated by whole counting. The results show that counting methods affected the universities in the middle range more than those in the upper or lower ranges. Citation counts were also more affected than paper counts. The correlation between the rankings generated from whole counting and those from the other methods were low or negative in the middle ranges. Based on the findings, this study concluded that straight counting and fractional counting were better choices for paper count and citation count in the institutional level research evaluation.  相似文献   

7.
One of the critical issues in bibliometric research assessments is the time required to achieve maturity in citations. Citation counts can be considered a reliable proxy of the real impact of a work only if they are observed after sufficient time has passed from publication date. In the present work the authors investigate the effect of varying the time of citation observation on accuracy of productivity rankings for research institutions. Research productivity measures are calculated for all Italian universities active in the hard sciences in the 2001–2003 period, by individual field and discipline, with the time of the citation observation varying from 2004 to 2008. The objective is to support policy-makers in choosing a citation window that optimizes the tradeoff between accuracy of rankings and timeliness of the exercise.  相似文献   

8.
Wide differences in publication and citation practices make impossible the direct comparison of raw citation counts across scientific disciplines. Recent research has studied new and traditional normalization procedures aimed at suppressing as much as possible these disproportions in citation numbers among scientific domains. Using the recently introduced IDCP (Inequality due to Differences in Citation Practices) method, this paper rigorously tests the performance of six cited-side normalization procedures based on the Thomson Reuters classification system consisting of 172 sub-fields. We use six yearly datasets from 1980 to 2004, with widely varying citation windows from the publication year to May 2011. The main findings are the following three. Firstly, as observed in previous research, within each year the shapes of sub-field citation distributions are strikingly similar. This paves the way for several normalization procedures to perform reasonably well in reducing the effect on citation inequality of differences in citation practices. Secondly, independently of the year of publication and the length of the citation window, the effect of such differences represents about 13% of total citation inequality. Thirdly, a recently introduced two-parameter normalization scheme outperforms the other normalization procedures over the entire period, reducing citation disproportions to a level very close to the minimum achievable given the data and the classification system. However, the traditional procedure of using sub-field mean citations as normalization factors yields also good results.  相似文献   

9.
文章借助CSSCI的统计数据,分析了2000-2009年数字图书馆建设体制及发展模式这一研究领域的发展情况,分析的主要指标有：发文情况、引文情况、被引著作、被引作者、关键词。通过研究发现,数字图书馆建设体制及发展这一领域已经在近十年得到了长足的发展,理论研究的深度和广度都在希断扩展,从宏观层面对我国数字图书馆事业的构建起到了积极的作用。  相似文献   

10.
Research evaluation based on bibliometrics is prevalent in modern science. However, the usefulness of citation counts for measuring research impact has been questioned for many years. Empirical studies have demonstrated that the probability of being cited might depend on many factors that are not related to the accepted conventions of scholarly publishing. The current study investigates the relationship between the performance of universities in terms of field-normalized citation impact (NCS) and four factors (FICs) with possible influences on the citation impact of single papers: journal impact factor (JIF), number of pages, number of authors, and number of cited references. The study is based on articles and reviews published by 49 German universities in 2000, 2005 and 2010. Multilevel regression models have been estimated, since multiple levels of data have been analyzed which are on the single paper and university level. The results point to weak relationships between NCSs and number of authors, number of cited references, number of pages, and JIF. Thus, the results demonstrate that there are similar effects of all FICs on NCSs in universities with high or low NCSs. Although other studies revealed that FICs might be effective on the single paper level, the results of this study demonstrate that they are not effective on the aggregated level (i.e., on the institutional NCSs level).  相似文献   

11.
In recent years there has been a sharp increase in collaborations among scholars and there are studies on the effects of scientific collaboration on scholars’ performance. This study examines the hypothesis that geographically diverse scientific collaboration is associated with research impact. Here, the approach is differentiated from other studies by: (a) focusing on publications rather than researchers or institutes; (b) considering the geographical diversity of authors of each publication; (c) considering the average number of citations a publication receives per year (time-based normalization of citations) as a surrogate for its impact; and (d) not focusing on a specific country (developed or developing) or region. Analysis of the collected bibliometric data shows that a publication impact is significantly and positively associated with all related geographical collaboration indicators. But publication impact has a stronger association with the numbers of external collaborations at department and institution levels (inter-departmental and inter-institutional collaborations) compared to internal collaborations. Conversely, national collaboration correlates better with impact than international collaboration.  相似文献   

12.
Abstract

This paper attempts to shed some light on the scientific communication behavior of Arab authors in library and information science by studying the characteristics of the literature used by these authors. A bibliometric study by way of citation analysis was conducted on the articles published from 1978 to 1988 in Maktabat Al-Idarah, an elite Arab scholarly journal in the field. It was concluded from this study that English literature is the main source of information for Arab authors in library and information science. They rely on English literature that is between 5 and 15 years of age more than on their own literature and use books more than any other form of publication. They cover almost all areas of the field with special emphasis on technical services as represented by cataloging, classification and aquisition, library administration and library education. Local materials published in their own country were also important.  相似文献   

13.
The role of Kazakhstan and other countries of the Commonwealth of Independent States in the global scientific landscape in 1996–2006 is analyzed on the basis of statistical data obtained from the Scopus database. The analysis of bibliometric indicators, publication activity, and citation per country and per field of study is presented in absolute terms and per population of a given country.  相似文献   

14.
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15.
[目的/意义]在引文分析中,可通过论文的一些属性特征对其未来的被引情况进行预测,并通过预测结果对论文、论文作者、作者所属机构及出版物做出评价。[方法/过程] 从出版物、作者和论文三个方面对影响论文被引的多个因素展开研究,以图书馆学情报学领域被SCI索引的论文作为分析及验证数据,使用逻辑回归、GBDT、XGBoost、AdaBoost、随机森林等算法进行预测,使用多组评测指标对比不同预测方法的效果,并使用GBDT识别对论文被引影响较大的因素。[结果/结论]确定三个方面的影响因素对论文被引预测的影响程度,构建预测模型,并较好地预测论文在未来一段时间的被引情况。大量实验分析发现GBDT、XGBoost和随机森林的预测能力较强,且预测的时间段越长,效果也就相对越好。  相似文献   

16.
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17.
In this paper, we investigate the effects of using four methods of publication counting (complete, whole, fractional, square root fractional) and limiting the number of publications (at researcher and institution levels) on the results of a national research evaluation exercise across fields using Polish data. We use bibliographic information on 0.58 million publications from the 2013–2016 period. Our analysis reveals that the largest effects are in those fields within which a variety publication and cooperation patterns can be observed (e.g. in Physical sciences or History and archeology). We argue that selecting the publication counting method for national evaluation purposes needs to take into account the current situation in the given country in terms of the excellence of research outcomes, level of internal, external and international collaboration, and publication patterns in the various fields of sciences. Our findings show that the social sciences and humanities are not significantly influenced by the different publication counting methods and limiting the number of publications included in the evaluation, as publication patterns in these fields are quite different from those observed in the so-called hard sciences. When discussing the goals of any national research evaluation system, we should be aware that the ways of achieving these goals are closely related to the publication counting method, which can serve as incentives for certain publication practices.  相似文献   

18.
The existing approaches to the definition of the scientific contributions made by researchers are analyzed. A bibliometric database is developed on the basis of the quantitative analysis of publication activities monitored by the most representative global citation systems, such as the Web of Science (Thomson Reuters, USA), Scopus (Elsevier, the Netherlands), and the Russian Science Citation Index (Scientific Electronic Library, the Russian Federation). The system allows teachers and researchers to consult their scientific publications (contained in Scopus, the WoS, and the RSCI),check citation levels and the h-index, filter data by the date of publication, and access the profiles of other researchers.  相似文献   

19.
《Journal of Informetrics》2019,13(2):738-750
An aspect of citation behavior, which has received longstanding attention in research, is how articles’ received citations evolve as time passes since their publication (i.e., citation ageing). Citation ageing has been studied mainly by the formulation and fit of mathematical models of diverse complexity. Commonly, these models restrict the shape of citation ageing functions and explicitly take into account factors known to influence citation ageing. An alternative—and less studied—approach is to estimate citation ageing functions using data-driven strategies. However, research following the latter approach has not been consistent in taking into account those factors known to influence citation ageing. In this article, we propose a model-free approach for estimating citation ageing functions which combines quantile regression with a non-parametric specification able to capture citation inflation. The proposed strategy allows taking into account field of research effects, impact level effects, citation inflation effects and skewness in the distribution of cites effects. To test our methodology, we collected a large dataset consisting of more than five million citations to 59,707 research articles spanning 12 dissimilar fields of research and, with this data in hand, tested the proposed strategy.  相似文献   

20.
[目的/意义]科研评价中,短时间引文窗口下的学科标准化指标往往是不可靠的,因为这时论文发表的时间较短,还没有充足的时间获取被引次数.然而,各种标准化方法本身并不能解决这一问题.研究旨在解决这一科研评价中的难题.[方法/过程]研究引入一个权重因素以表示每篇论文标准分的可靠程度,权重由论文在给定的短时间窗口下的被引次数与长...  相似文献   

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