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1.
This study compares the two-year impact factor (JIF2), JIF2 without journal self-citation (JIF2_noJSC), five-year impact factor (JIF5), eigenfactor score and article influence score (AIS) and investigates their relative changes with time. JIF2 increased faster than JIF5 overall. The relative change between JIF2 and JIF_noJSC shows that the control of JCR over journal self-citation is effective to some extent. JIF5 is more discriminative than JIF2. The correlation between JIF5 and AIS is stronger than that between JIF5 and the eigenfactor score. The relative change in journal rank according to different indicators varies with the ratio of the indicators and can be up to 60 % of the number of journals in a subject category. There is subject category discrepancy in the average AIS and its change over time. Through the screening of journals according to variations in the ratio of JIF2 to JIF5 for journals in individual subject categories, we found that journals in the same subject categories can have considerably different citation patterns. To provide a fair comparison of journals in individual subject categories, we argue that it is better to replace JIF2 with the ready-made JIF5 when ranking journals.  相似文献   

2.
The purpose of the study was to investigate and compare the social media (SM) impact of 273 South Africa Post-Secondary Education accredited journals, which are recognised by the Department of Higher Education and Training of South Africa for purposes of financial support. We used multiple sources to extract data for the study, namely, Altmetric.com, Google Scholar (GS), Scopus (through SCImago) and the Thomson Reuters (TR) Journal Citation Reports (JCR). Data was analysed to determine South African journals’ presence in and impact on SM as well as to contrast SM visibility and impact with the citation impact in GS, JCR and Scopus. The Spearman correlation test was performed to compare the impact of the journals on SM and other sources. The results reveal that 2923 articles published in 122 of the 273 South African (SA) journals have received at least one mention in SM; the most commonly used SM platforms were Twitter and Facebook; the journals indexed in the TR’s citation indexes and Scopus performed much better, in terms of their average altmetrics, than non-TR and non-Scopus indexed journals; and there were weak to moderate relationships among different types of altmetrics and citation-based measures, thereby implying different kinds of journal impacts on SM when compared to the scholarly impact reflected in citation databases. In conclusion, South African journals’ impact on SM, just as is the case with countries with similar economies, is minimal but has shown signs of growth.  相似文献   

3.
This research explores the performance of Asian S&T journals based on the outcomes of various citation indicators. Indexed by Journal Citation Reports – Science Citation Index Expanded (JCR‐SCIE), journals published in China, Japan, India, Singapore, South Korea, and Taiwan between the years 2008 and 2012 are collected and analysed using bibliometrics and statistics methods. Results showed that the mean impact factor (IF) value of the journals from all countries was less than 1.3 throughout the period. Only journals from China and Japan had a mean IF or 5‐year IF (5Y‐IF) value exceeding 1. The self‐cited rate of the journals from South Korea remained the highest among selected countries but showed a declining trend every year. The self‐cited rates among journals from all the six Asian countries did not considerably affect the journals’ IF values. The results revealed that the IF‐based ranking factor (IF‐RF) of Chinese and Japanese journals in various subject fields constantly improved from 2008 to 2012, but this improvement trend was not observed in journals from the other four countries. Overall, the journals from Japan and China demonstrated stronger impacts than those from the other countries.  相似文献   

4.
SCI收录中日韩印4国期刊引文指标的比较   总被引:3,自引:2,他引:1  
以JCR 2006—2008年的数据为基础,将我国与日本、韩国、印度的各项指标作比较,结果表明我国内地被SC I收录的期刊与论文在数量和质量方面都呈快速增长态势,虽与欧美有较大差距,但在亚洲明显超过印度,部分指标超过了我国台湾与韩国,仅次于日本。这启示我们:不必妄自菲薄,认为我国期刊质量都不如国外;当然,也要看到差距,努力争取更大的国际影响。  相似文献   

5.
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   

6.
In 2021, Clarivate published a new version of the Journal Citation Reports (JCR) including a new indicator. The Journal Citation Indicator (JCI) is a new field-normalized metric at journal-level, which is calculated by averaging the Category Normalized Citation Impact (CNCI) of the journal's articles and reviews published in the preceding three-year period. Unlike the Journal Impact Factor (JIF), it is also calculated for the journals of the Arts & Humanities Citation Index (AHCI) and the Emerging Sources Citation Index (ESCI), which are now included in the JCR. To better understand this new indicator, this article analyses its main statistical characteristics in comparison with the other JCR indicators using all JCR journals and categories. The results highlight the similarities between the JCI and JIF, with a high Pearson correlation (0.853) and a similar distribution. This correlation is also high and homogeneous in the different categories, both for Science and Social Sciences. The JCI is therefore a perfect complement to the JIF, as well as representing an alternative to resolve the well-known problems of the JCR.  相似文献   

7.
The journal impact factor (JIF) is the average of the number of citations of the papers published in a journal, calculated according to a specific formula; it is extensively used for the evaluation of research and researchers. The method assumes that all papers in a journal have the same scientific merit, which is measured by the JIF of the publishing journal. This implies that the number of citations measures scientific merits but the JIF does not evaluate each individual paper by its own number of citations. Therefore, in the comparative evaluation of two papers, the use of the JIF implies a risk of failure, which occurs when a paper in the journal with the lower JIF is compared to another with fewer citations in the journal with the higher JIF. To quantify this risk of failure, this study calculates the failure probabilities, taking advantage of the lognormal distribution of citations. In two journals whose JIFs are ten-fold different, the failure probability is low. However, in most cases when two papers are compared, the JIFs of the journals are not so different. Then, the failure probability can be close to 0.5, which is equivalent to evaluating by coin flipping.  相似文献   

8.
The journal impact factor (JIF) reported in journal citation reports has been used to represent the influence and prestige of a journal. Whereas the consideration of the stochastic nature of a statistic is a prerequisite for statistical inference, the estimation of JIF uncertainty is necessary yet unavailable for comparing the impact among journals. Using journals in the Database of Research in Science Education (DoRISE), the current study proposes bootstrap methods to estimate the JIF variability. The paper also provides a comprehensive exposition of the sources of JIF variability. The collections of articles in the year of interest and in the preceding years both contribute to JIF variability. In addition, the variability estimate differs depending on the way a database selects its journals for inclusion. In the bootstrap process, the nested structure of articles in a journal was accounted for to ensure that each bootstrap replication reflects the actual citation characteristics of articles in the journal. In conclusion, the proposed point and interval estimates of the JIF statistic are obtained and more informative inferences on the impact of journals can be drawn.  相似文献   

9.
期刊引用认同指标在期刊评价中的适用性分析   总被引:1,自引:1,他引:0  
论文以CSSCI图书情报领域的18种期刊为例,以这些期刊在2009年全年登载论文的参考文献为研究对象,从CSSCI数据库中获取数据,统计分析各期刊的引用认同。结果显示:期刊引用认同指标(引文量、篇均引文量、英文引文比、期刊引用广度、自施引率、引用半衰期、期刊集中因子、认同期刊影响力等指标)与CSSCI来源期刊定量与定性评价指标并不明显相关,但这类指标可以反映期刊载文的内容特征与偏好、对国外科学文献和对其他学科文献的利用程度、期刊的办刊定位、学科的发展模式等等,在综合评价期刊方面具有一定意义。  相似文献   

10.
JCR五年期影响因子探析   总被引:6,自引:0,他引:6  
使用期刊引证报告(JCR)6015种期刊数据,以统计学方法探索性地分析5年期影响因子IF5的特点.结果显示,IF5作为具有代表性的平均性期刊评价指标,能更好地反映多数期刊被引高峰,总体符合布拉德福分布.IF5与2年期影响因子IF存在排序相关,也有显著统计学差异,两者测评结果在较好和较差期刊上相对一致,但在多数水平居中的期刊上存在区别.最后,给出Ifa指数测度两种影响因子的差别和Ifb指数综合两种影响因子的评价信息.  相似文献   

11.
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   

12.
This study examines the extent of concentration in the journal publishing industry. A number of aspects are considered: publishers, journal impacts, countries, and languages. For journals indexed in JCR from 1997 to 2009, just 0.2% of publishers produce 50% of journals and articles, and 0.3% of publishers account for the top 50% of citations, impact factors and immediacy indices. More than a half of publishers in JCR are from four countries: USA, UK, Germany and Japan. In addition, more than a half of journals come from the USA and UK. Examining the publishers' interactions in terms of buying and selling journals shows the extent of change by acquisition, and the acquisition links between publishers. The findings confirm that the international market of journal publishing is essentially dominated by a few publishers.  相似文献   

13.
中国作者对发表SCI论文有巨大的需求,但目前SCIE收录的中国期刊数量较少,且总体水平未达到世界平均水平。将SCI-E收录的中国期刊根据语种和论文作者的国籍进行分类后发现:甲类期刊(以中文刊载的论文大于50%)和乙类期刊(发表论文的作者至少50%来自中国,且至少50%的论文以英文形式发表)学术水平未达到国际平均水平,2001—2011年期间变化不大;但乙类期刊是SCI-E收录的中国期刊中的绝大多数。丙类期刊(其刊载的论文至少50%是以英文发表的,且至少50%的论文第一作者为非中国作者)引用指数(JCS)逐年上升,上升幅度明显,2011年超过国际平均水平。说明通过改变语种不能提高期刊的国际影响力。在这3类期刊中,丙类年刊均载文量最低,为117.27篇/刊,2007后呈逐年下降趋势,2011年甚至降至91.07篇/刊。中国被SCI-E收录的期刊数量少,与国内发表SCI论文的巨大需求,以及中国期刊走上国际舞台,发挥更大的学术影响力的需求差距甚远,的确有必要创办更多的英文科技期刊;但是在此过程中,有必要慎重评价SCI-E收录期刊的学术影响力和作用。  相似文献   

14.
The journal impact factor (JIF) has been questioned considerably during its development in the past half-century because of its inconsistency with scholarly reputation evaluations of scientific journals. This paper proposes a publication delay adjusted impact factor (PDAIF) which takes publication delay into consideration to reduce the negative effect on the quality of the impact factor determination. Based on citation data collected from Journal Citation Reports and publication delay data extracted from the journals’ official websites, the PDAIFs for journals from business-related disciplines are calculated. The results show that PDAIF values are, on average, more than 50% higher than JIF results. Furthermore, journal ranking based on PDAIF shows very high consistency with reputation-based journal rankings. Moreover, based on a case study of journals published by ELSEVIER and INFORMS, we find that PDAIF will bring a greater impact factor increase for journals with longer publication delay because of reducing that negative influence. Finally, insightful and practical suggestions to shorten the publication delay are provided.  相似文献   

15.
Countries in East Asia – specifically China, Japan, and South Korea – are rapidly emerging as major contributors to global research output. However, owing to barriers in language and culture, it is possible that authors from these countries face unique challenges in getting published. Moreover, as submissions from these countries increase, journal editors may be able to spot some trends in the problems encountered when processing these submissions. This study presents the results of two surveys – one involving non‐native English‐speaking authors from East Asia and another involving international journal editors. The surveys were designed to throw light on the challenges East Asian authors face in the publication process and the perceptions journal editors have of submissions from East Asian countries. Here, we present and discuss the survey results, highlight gaps in the perspectives of authors and journal editors, and make recommendations to bridge these gaps.  相似文献   

16.
以SJR为数据来源,比较分析了1996-2008年巴西、印度、中国、韩国4个国家发表科技论文数量、可引用文献量、文献被引量、自引量、篇均被引量、去除自引后的篇均被引量、H指数、文献引用率、国际合作量等9个指标。中国发表论文数最多,2003年后每年增加约3万篇。巴西、韩国文献引用率、篇均引用量高,且自引率低;印度居中等水平;中国文献引用率、篇均引用率低且自引率高;国际合作度巴西最高、中国最低。可见中国的科技论文质量与其他3个国家相比,还有一定的差距。  相似文献   

17.
期刊PR8指数:一个新的跨学科期刊评价指标及其实证研究   总被引:1,自引:0,他引:1  
[目的/意义] 基于论文被引频次8个区段百分位数排序(percentile rank 8,PR8)赋分,尝试构建新的跨学科期刊评价指标:期刊PR8指数(journal index for PR8,JIPR8),并检验JIPR8的跨学科期刊评价效果。[方法/过程] 选择JCR中8个学科301种期刊作为研究对象,分别计算每种期刊的JIPR8,并与其他几个跨学科期刊评价指标进行比较,检验JIPR8跨学科期刊评价的敏感度和稳定性,以及与其他跨学科期刊评价指标的相关性。[结果/结论] 在选择的所有指标中,8个学科301种期刊JIPR8的变异程度最低,说明其用于跨学科期刊评价的稳定性最好;不同分区期刊(Q1、Q2、Q3和Q4) JIPR8的组间差异性较为明显,仅次于期刊影响因子百分位(journal impact factor pencentile,JIFP),表明其对优秀和一般期刊的区分度较好。认为JIPR8是一个非常理想的跨学科期刊评价指标。  相似文献   

18.
选取中国和日本被JCR收录的期刊作为研究对象,从JCR中获取2001—2005年的相关数据,并从总被引次数、影响因子、即年指标和载文量四个方面对两国的学术期刊进行详细比较和分析。通过以上比较和分析,得出几点重要结论。  相似文献   

19.
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   

20.
文章以2010年被SCI收录的文献类型为ARTICLE和REVIEW的数据为基础,利用JCR提供的国际期刊文献计量指标,从发表论文期刊的国别、影响因子和我国国际论文的学科分布等视角分析研究了我国国际论文的发表态势,同时从国际期刊发表我国国际论文的发文量与影响因子的关系的角度研究了我国国际论文对国际期刊的贡献率。  相似文献   

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