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1.
A new size-independent indicator of scientific journal prestige, the SJR2 indicator, is proposed. This indicator takes into account not only the prestige of the citing scientific journal but also its closeness to the cited journal using the cosine of the angle between the vectors of the two journals’ cocitation profiles. To eliminate the size effect, the accumulated prestige is divided by the fraction of the journal's citable documents, thus eliminating the decreasing tendency of this type of indicator and giving meaning to the scores. Its method of computation is described, and the results of its implementation on the Scopus 2008 dataset is compared with those of an ad hoc Journal Impact Factor, JIF(3y), and SNIP, the comparison being made both overall and within specific scientific areas. All three, the SJR2 indicator, the SNIP indicator and the JIF distributions, were found to fit well to a logarithmic law. Although the three metrics were strongly correlated, there were major changes in rank. In addition, the SJR2 was distributed more equalized than the JIF by Subject Area and almost as equalized as the SNIP, and better than both at the lower level of Specific Subject Areas. The incorporation of the cosine increased the values of the flows of prestige between thematically close journals.  相似文献   

2.
Publication patterns of 79 forest scientists awarded major international forestry prizes during 1990-2010 were compared with the journal classification and ranking promoted as part of the ‘Excellence in Research for Australia’ (ERA) by the Australian Research Council. The data revealed that these scientists exhibited an elite publication performance during the decade before and two decades following their first major award. An analysis of their 1703 articles in 431 journals revealed substantial differences between the journal choices of these elite scientists and the ERA classification and ranking of journals. Implications from these findings are that additional cross-classifications should be added for many journals, and there should be an adjustment to the ranking of several journals relevant to the ERA Field of Research classified as 0705 Forestry Sciences.  相似文献   

3.
期刊评价指标SJR、JIF和H指数的关系研究   总被引:4,自引:1,他引:3  
以SSCI与SCOPUS收录重合的38种国际图书情报期刊为例,通过Spearman相关系数对SJR、JIF和H指数三种学术期刊评价指标之间关系进行研究,并对三者的优缺点进行归纳。结果表明,SJR、JIF和H指数三者呈线性关系,但由于SJR同时兼顾期刊被引数量与质量而更优。最后,对这些评价指标进行探讨与展望。  相似文献   

4.
This research study evaluates the quality of articles published by Saudi and expatriate authors in foreign Library and Information Science (LIS) journals using three popular metrics for ranking journals—Journal Impact Factor (JIF), SCImago Journal Rank (SJR), and Google Scholar Metrics (GSM). The reason for using multiple metrics is to see how closely or differently journals are ranked by the three different methods of citation analysis. However, the 2012 JIF list of journals is too small, almost half the size of the SJR and GSM lists, which inhibited one-to-one comparison among the impact factors of the thirty-six journals selected by Saudi authors for publishing articles. Only seventeen journals were found common to all the three lists, limiting the usefulness of the data. A basic problem is that Saudi LIS authors generally lack the level of competency in the English language required to achieve publication in the most prominent LIS journals. The study will have implications for authors, directors, and deans of all types of academic libraries; chairmen and deans of library schools; and the Saudi Library Association. Hopefully these entities will take necessary steps to prepare and motivate both academics and practicing librarians to improve the quality of their research and publications and thus get published in higher ranked journals.  相似文献   

5.
The aim of this study was to determine whether different areas of knowledge presented different behaviour with regard to the number of references cited per journal document or if, conversely, they shared the same reference density practices. Bibliometric and bibliographic data were collected from 27,141 journals (indexed between 2001 and 2015 in the SCImago Journal & Country Rank (SJR)) and the growth rates in reference density and number of documents and journals in each category were calculated at different levels of aggregation.Our analysis identified that (a) mean reference density values in some Social Sciences and Arts and Humanities categories were equal to or higher than those in the “hard sciences”; (b) reference density growth rates in these disciplines were not as high as those in the hard sciences and, in general, did not correspond with growth rates in the number of documents produced; (c) this can be considered an indication that citation-based evaluation practices affect publication habits; and (d) no significant differences were found in mean values or growth rates between Gold Open Access and Non Gold Open Access journals.  相似文献   

6.
This study established a technological impact factor (TIF) derived from journal impact factor (JIF), which is proposed to evaluate journals from the aspect of practical innovation. This impact factor mainly examines the influence of journal articles on patents by calculating the number of patents cited to a journal divided by the number of articles published in that particular journal. The values of TIF for five-year (TIF5) and ten-year (TIF10) periods at the journal level and aggregated TIF values (TIFAGG_5 and TIFAGG_10) at the category level were provided and compared to the JIF. The results reveal that journals with higher TIF values showed varied performances in the JCR, while the top ten journals on JIF5 showed consistent good performance in TIFs. Journals in three selected categories – Electrical & Electronic Engineering, Research & Experimental Medicine, and Organic Chemistry – showed that TIF5 and TIF10 values are not strongly correlated with JIF5. Thus, TIFs can provide a new indicator for evaluating journals from the aspect of practical innovation.  相似文献   

7.
8.
李武  刘宇 《出版科学》2012,20(3):17-24
基于期刊共被引数据,本研究利用分层聚类和多维尺度分析方法考察新闻传播学期刊的集群分布及彼此之间的亲疏关系。数据分析表明:(1)新闻传播学期刊首先区分为新闻传播类期刊和编辑出版类期刊两大分支。(2)在新闻传播类期刊中,《电视研究》和《中国广播电视学刊》两者关系密切,但与其他期刊关系疏远。其他期刊按其亲疏关系又大致区分为两类:以学术研究为主导的研究型期刊和以实践总结为主导的行业性期刊。(3)在编辑出版类期刊中,《读书》和《中国图书评论》两者关系密切,但与其他期刊关系疏远。其他期刊按其亲疏关系又大致区分为三类:科技编辑出版类期刊、以出版为重点的出版类期刊和以编辑为重点的编辑类期刊。  相似文献   

9.
Journal metrics are employed for the assessment of scientific scholar journals from a general bibliometric perspective. In this context, the Thomson Reuters journal impact factors (JIFs) are the citation-based indicators most used. The 2-year journal impact factor (2-JIF) counts citations to one and two year old articles, while the 5-year journal impact factor (5-JIF) counts citations from one to five year old articles. Nevertheless, these indicators are not comparable among fields of science for two reasons: (i) each field has a different impact maturity time, and (ii) because of systematic differences in publication and citation behavior across disciplines. In fact, the 5-JIF firstly appeared in the Journal Citation Reports (JCR) in 2007 with the purpose of making more comparable impacts in fields in which impact matures slowly. However, there is not an optimal fixed impact maturity time valid for all the fields. In some of them two years provides a good performance whereas in others three or more years are necessary. Therefore, there is a problem when comparing a journal from a field in which impact matures slowly with a journal from a field in which impact matures rapidly. In this work, we propose the 2-year maximum journal impact factor (2M-JIF), a new impact indicator that considers the 2-year rolling citation time window of maximum impact instead of the previous 2-year time window. Finally, an empirical application comparing 2-JIF, 5-JIF, and 2M-JIF shows that the maximum rolling target window reduces the between-group variance with respect to the within-group variance in a random sample of about six hundred journals from eight different fields.  相似文献   

10.
首先基于对期刊文献资源特点与价值的认识,提出期刊文献数据库计量分析 功能的开发问题;然后,分别从简单计数统计、历时性分析、共时性分析、引 用关系聚类分析、基于期刊专业性指标的计量分析等5个方面,比较全面系统 地阐述了期刊文献数据库计量分析功能的构想;最后,对计量分析功能及其实 现问题进行了简单讨论。  相似文献   

11.
SJR与影响因子、H指数的比较及SJR的扩展设想   总被引:15,自引:3,他引:12  
介绍了SCImago Journal Rank(SJR)及其计算过程,使用因子分析、回归及相关分析等方法实证研究了SJR与期刊影响因子、期刊h指数的关系。结果表明:SJR与期刊影响因子和期刊h指数均有较强正相关性;SJR与期刊影响因子的联合判定可区别出期刊在流行与声望两个维度上的特点;SJR和期刊引文及参考文献的平均性指标具有较强内部关联性,而期刊h指数则与总体性指标内部关联较强。提出了标准化SJR用于解决SJR不能跨学科比较的问题,提出了期刊声望演化指数用于衡量期刊声望的演变趋势,并将SJR的运用范围扩展到了学科和国家层次。  相似文献   

12.
Recent advances in methods and techniques enable us to develop interactive overlays to a global map of science based on aggregated citation relations among the 9162 journals contained in the Science Citation Index and Social Science Citation Index 2009. We first discuss the pros and cons of the various options: cited versus citing, multidimensional scaling versus spring-embedded algorithms, VOSViewer versus Gephi, and the various clustering algorithms and similarity criteria. Our approach focuses on the positions of journals in the multidimensional space spanned by the aggregated journal–journal citations. Using VOSViewer for the resulting mapping, a number of choices can be left to the user; we provide default options reflecting our preferences. Some examples are also provided; for example, the potential of using this technique to assess the interdisciplinarity of organizations and/or document sets.  相似文献   

13.
14.
引文评价新指标SNIP旨在评价不同主题领域期刊影响力。从理论上对比分析SNIP与IF、h指数、SJR指标值的原理、关系,各自的优缺点以及它们的应用区别。结果表明,理论上SNIP与其他3个指标存在关联性,具有一定的优势,可用于期刊评价实践中。  相似文献   

15.
This paper explores a new indicator of journal citation impact, denoted as source normalized impact per paper (SNIP). It measures a journal's contextual citation impact, taking into account characteristics of its properly defined subject field, especially the frequency at which authors cite other papers in their reference lists, the rapidity of maturing of citation impact, and the extent to which a database used for the assessment covers the field's literature. It further develops Eugene Garfield's notions of a field's ‘citation potential’ defined as the average length of references lists in a field and determining the probability of being cited, and the need in fair performance assessments to correct for differences between subject fields. A journal's subject field is defined as the set of papers citing that journal. SNIP is defined as the ratio of the journal's citation count per paper and the citation potential in its subject field. It aims to allow direct comparison of sources in different subject fields. Citation potential is shown to vary not only between journal subject categories – groupings of journals sharing a research field – or disciplines (e.g., journals in mathematics, engineering and social sciences tend to have lower values than titles in life sciences), but also between journals within the same subject category. For instance, basic journals tend to show higher citation potentials than applied or clinical journals, and journals covering emerging topics higher than periodicals in classical subjects or more general journals. SNIP corrects for such differences. Its strengths and limitations are critically discussed, and suggestions are made for further research. All empirical results are derived from Elsevier's Scopus.  相似文献   

16.
We study the correlation between citation-based and expert-based assessments of journals and series, which we collectively refer to as sources. The source normalized impact per paper (SNIP), the Scimago Journal Rank 2 (SJR2) and the raw impact per paper (RIP) indicators are used to assess sources based on their citations, while the Norwegian model is used to obtain expert-based source assessments. We first analyze – within different subject area categories and across such categories – the degree to which RIP, SNIP and SJR2 values correlate with the quality levels in the Norwegian model. We find that sources at higher quality levels on average have substantially higher RIP, SNIP, and SJR2 values. Regarding subject area categories, SNIP seems to perform substantially better than SJR2 from the field normalization point of view. We then compare the ability of RIP, SNIP and SJR2 to predict whether a source is classified at the highest quality level in the Norwegian model or not. SNIP and SJR2 turn out to give more accurate predictions than RIP, which provides evidence that normalizing for differences in citation practices between scientific fields indeed improves the accuracy of citation indicators.  相似文献   

17.
A size-independent indicator of journals’ scientific prestige, the SCImago Journal Rank (SJR) indicator, is proposed that ranks scholarly journals based on citation weighting schemes and eigenvector centrality. It is designed for use with complex and heterogeneous citation networks such as Scopus. Its computation method is described, and the results of its implementation on the Scopus 2007 dataset is compared with those of an ad hoc Journal Impact Factor, JIF(3y), both generally and within specific scientific areas. Both the SJR indicator and the JIF distributions were found to fit well to a logarithmic law. While the two metrics were strongly correlated, there were also major changes in rank. In addition, two general characteristics were observed. On the one hand, journals’ scientific influence or prestige as computed by the SJR indicator tended to be concentrated in fewer journals than the quantity of citation measured by JIF(3y). And on the other, the distance between the top-ranked journals and the rest tended to be greater in the SJR ranking than in that of the JIF(3y), while the separation between the middle and lower ranked journals tended to be smaller.  相似文献   

18.
Journal weighted impact factor: A proposal   总被引:3,自引:0,他引:3  
The impact factor of a journal reflects the frequency with which the journal's articles are cited. It is the best available measure of journal quality. For calculation of impact factor, we just count the number of citations, no matter how prestigious the citing journal is. We think that impact factor as a measure of journal quality, may be improved if in its calculation, we not only take into account the number of citations, but also incorporate a factor reflecting the prestige of the citing journals relative to the cited journal. In calculation of this proposed “weighted impact factor,” each citation has a coefficient (weight) the value of which is 1 if the citing journal is as prestigious as the cited journal; is >1 if the citing journal is more prestigious than the cited journal; and is <1 if the citing journal has a lower standing than the cited journal. In this way, journals receiving many citations from prestigious journals are considered prestigious themselves and those cited by low-status journals seek little credit. By considering both the number of citations and the prestige of the citing journals, we expect the weighted impact factor be a better scientometrics measure of journal quality.  相似文献   

19.
我国海洋科学类期刊评价中的SJR指数应用研究   总被引:2,自引:0,他引:2  
介绍SCImago Journal Rank(SJR)指数的原理、特征和计算方法,将其应用于我国海洋科学类期刊的分析研究,通过数据统计和程序运算,得出我国海洋科学类期刊SJR指数值,并根据结果进行数值分析、与影响因子联合分析,总结了SJR在海洋科学类期刊评价中的优势,为我国海洋科学类期刊的学科发展和科学评价提供参考。  相似文献   

20.
篇均来源期刊标准影响(SNIP)为荷兰学者Moed教授于2010年提出的全新期刊评价指标,旨在对不同主题领域的期刊影响力进行评价,为验证这一评价指标在期刊评价实践中的效用,利用SPSS18.0数据统计分析软件对Scopus数据库中24种外文期刊的SNIP与SJR、h指数以及影响因子进行实证对比分析;以CSSCI为来源数据库统计分析国内6种图书情报学期刊的IF值与SNIP值。分析结果证明,SNIP与其他3个指标之间存在较强的相关性,在期刊评价实践中具有可行性。  相似文献   

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