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1.
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   

2.
基于期刊引用形象和期刊引用认同的期刊评价   总被引:2,自引:0,他引:2  
介绍了期刊引用形象和期刊引用认同的概念;修正了Bonnevie-Nebelong选择的期刊评价指标;对现有期刊评价指标从期刊引用形象和期刊引用认同的角度进行划分;提出了新的期刊引用认同评价指标:新学科扩散指标、新学科影响指标、新即年指标、新引用刊数、新他引率;分析新指标的期刊评价意义;最后以图情领域的三种期刊进行实证分析。  相似文献   

3.
网络中心度用于期刊引文评价的有效性研究   总被引:1,自引:0,他引:1  
以图书情报学期刊数据实证研究了网络中心度用于期刊引文评价的有效性。结果显示:中介、点度和特征向量中心度都比影响因子更接近同行评议的结果,可用于期刊引文评价;但接近中心度相对不宜用作期刊引文评价指标。  相似文献   

4.
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   

5.
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   

6.
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   

7.
中心度指标在期刊引文网络分析中的运用及改进   总被引:2,自引:1,他引:1  
利用ISI的期刊引证报告(JCR)社会科学版,收集国际图书情报学56种期刊2005-2007年的引证数据,尝试研究社会网络中心度指标在期刊引文网络分析中的运用。发现原来的中心度指标忽略了期刊刊载论文的数量对于期刊总被引频次的影响,针对原有指标的不足,给出平均中心度这一改进型中心度指标,并运用探索性因子分析探究各中心度指标间的相互关系。  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.
One of the flaws of the journal impact factor (IF) is that it cannot be used to compare journals from different fields or multidisciplinary journals because the IF differs significantly across research fields. This study proposes a new measure of journal performance that captures field-different citation characteristics. We view journal performance from the perspective of the efficiency of a journal's citation generation process. Together with the conventional variables used in calculating the IF, the number of articles as an input and the number of total citations as an output, we additionally consider the two field-different factors, citation density and citation dynamics, as inputs. We also separately capture the contribution of external citations and self-citations and incorporate their relative importance in measuring journal performance. To accommodate multiple inputs and outputs whose relationships are unknown, this study employs data envelopment analysis (DEA), a multi-factor productivity model for measuring the relative efficiency of decision-making units without any assumption of a production function. The resulting efficiency score, called DEA-IF, can then be used for the comparative evaluation of multidisciplinary journals’ performance. A case study example of industrial engineering journals is provided to illustrate how to measure DEA-IF and its usefulness.  相似文献   

10.
社会科学引文的离散性研究——基于JCR社科版指标分析   总被引:1,自引:0,他引:1  
《期刊引证报告》(JCR)是美国科技信息研究所于1975年出版的一种独特的多学科期刊分析评价工具。通过对2005年的JCR社会科学版数据的统计分析可知,社会科学引文在基本符合布拉德福定律的情况下离散程度有所缩小,在社会科学领域较多的期刊承担着学术交流任务,因此不能笼统地说社会科学引文在期刊中的分布符合布拉德福定律,而应该注意到它的集中分散有一定的特殊性。  相似文献   

11.
H指数和G指数——期刊学术影响力评价的新指标   总被引:30,自引:0,他引:30  
首先利用《中文社会科学引文索引》的检索数据,以图书馆学情报学部分期刊为例,比较各期刊H指数和相对H指数的大小及其特点;其次利用CNKI的系列引文数据库,对部分图书馆学情报学和管理学期刊的G指数进行比较研究,认为H指数与相对H指数、相对H指数与影响因子之间存在较大的相关性;最后指出使用H指数、相对H指数和G指数应坚持同类相比原则,在期刊评价中应慎重使用。  相似文献   

12.
Citation based approaches, such as the impact factor and h-index, have been used to measure the influence or impact of journals for journal rankings. A survey of the related literature for different disciplines shows that the level of correlation between these citation based approaches is domain dependent. We analyze the correlation between the impact factors and h-indices of the top ranked computer science journals for five different subjects. Our results show that the correlation between these citation based approaches is very low. Since using a different approach can result in different journal rankings, we further combine the different results and then re-rank the journals using a combination method. These new ranking results can be used as a reference for researchers to choose their publication outlets.  相似文献   

13.
In the present paper the Percentage Rank Position (PRP) index concluding from the principle of Similar Distribution of Information Impact in different fields of science (Vinkler, 2013), is suggested to assess journals in different research fields comparatively. The publications in the journals dedicated to a field are ranked by citation frequency, and the PRP-index of the papers in the elite set of the field is calculated. The PRP-index relates the citation rank number of the paper to the total number of papers in the corresponding set. The sum of the PRP-index of the elite papers in a journal, PRP(j,F) may represent the eminence of the journal in the field. The non-parametric and non-dimensional PRP(j,F) index of journals is believed to be comparable across fields.  相似文献   

14.
This study uses citation data and survey data for 55 library and information science journals to identify three factors underlying a set of 11 journal ranking metrics (six citation metrics and five stated preference metrics). The three factors—three composite rankings—represent (1) the citation impact of a typical article, (2) subjective reputation, and (3) the citation impact of the journal as a whole (all articles combined). Together, they account for 77% of the common variance within the set of 11 metrics. Older journals (those founded before 1953) and nonprofit journals tend to have high reputation scores relative to their citation impact. Unlike previous research, this investigation shows no clear evidence of a distinction between the journals of greatest importance to scholars and those of greatest importance to practitioners. Neither group's subjective journal rankings are closely related to citation impact.  相似文献   

15.
期刊引用认同及其被引评价新指标有效性分析   总被引:2,自引:1,他引:1  
以影响因子等引文数据为核心的期刊评价指标体系虽广为使用,但也备受争议.本文从期刊引用认同、期刊被引及期刊国际化等三个方面分析了不仅仅依赖于"影响因子"的评价期刊的新指标,并对相关指标的有效性问题进行讨论.分析表明,基于期刊引用认同视角和基于期刊被引网络视角的很多指标可以与期刊影响因子指标相印证,可用作国内期刊评价的新尝试,而相关期刊国际化评价指标还需在实践中进一步检验.  相似文献   

16.
基于《中文社会科学引文索引》的分析表明 ,《中国图书馆学报》在图书情报学研究领域具有很大的社会影响 ,其论文被引次数、影响因子 ,以及同行专家的评价结果 ,在我国图书馆学、情报学期刊群中均名列第一。表 12。参考文献 6  相似文献   

17.
Altmetrics from Altmetric.com are widely used by publishers and researchers to give earlier evidence of attention than citation counts. This article assesses whether Altmetric.com scores are reliable early indicators of likely future impact and whether they may also reflect non-scholarly impacts. A preliminary factor analysis suggests that the main altmetric indicator of scholarly impact is Mendeley reader counts, with weaker news, informational and social network discussion/promotion dimensions in some fields. Based on a regression analysis of Altmetric.com data from November 2015 and Scopus citation counts from October 2017 for articles in 30 narrow fields, only Mendeley reader counts are consistent predictors of future citation impact. Most other Altmetric.com scores can help predict future impact in some fields. Overall, the results confirm that early Altmetric.com scores can predict later citation counts, although less well than journal impact factors, and the optimal strategy is to consider both Altmetric.com scores and journal impact factors. Altmetric.com scores can also reflect dimensions of non-scholarly impact in some fields.  相似文献   

18.
Do academic journals favor authors who share their institutional affiliation? To answer this question we examine citation counts, as a proxy for paper quality, for articles published in four leading international relations journals during the years 2000–2015. We compare citation counts for articles written by “in-group members” (authors affiliated with the journal’s publishing institution) versus “out-group members” (authors not affiliated with that institution). Articles written by in-group authors received 18% to 49% fewer Web of Science citations when published in their home journal (International Security or World Politics) vs. an unaffiliated journal, compared to out-group authors. These results are mainly driven by authors who received their PhDs from Harvard or MIT. The findings show evidence of a bias within some journals towards publishing papers by faculty from their home institution, at the expense of paper quality.  相似文献   

19.
论文基于CSSCI对《新世纪图书馆》载文被来源期刊引用情况进行计量分析,研究并揭示了该刊载文被引特征,进而为该刊早日跻身CSSCI来源期刊榜提出可行性建议。  相似文献   

20.
In a recent paper in the Journal of Informetrics, Habibzadeh and Yadollahie [Habibzadeh, F., & Yadollahie, M. (2008). Journal weighted impact factor: A proposal. Journal of Informetrics, 2(2), 164–172] propose a journal weighted impact factor (WIF). Unlike the ordinary impact factor, the WIF of a journal takes into account the prestige or the influence of citing journals. In this communication, we show that the way in which Habibzadeh and Yadollahie calculate the WIF of a journal has some serious problems. Due to these problems, a ranking of journals based on WIF can be misleading. We also indicate how the problems can be solved by changing the way in which the WIF of a journal is calculated.  相似文献   

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