首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
The journal impact factor is not comparable among fields of science and social science because of systematic differences in publication and citation behavior across disciplines. In this work, a source normalization of the journal impact factor is proposed. We use the aggregate impact factor of the citing journals as a measure of the citation potential in the journal topic, and we employ this citation potential in the normalization of the journal impact factor to make it comparable between scientific fields. An empirical application comparing some impact indicators with our topic normalized impact factor in a set of 224 journals from four different fields shows that our normalization, using the citation potential in the journal topic, reduces the between-group variance with respect to the within-group variance in a higher proportion than the rest of indicators analyzed. The effect of journal self-citations over the normalization process is also studied.  相似文献   

2.
This paper takes the cue from the case of a retracted paper, cited both by the retraction notice and by an article published later in the same journal. This led to analysis and discussion on the skewness of citations in the journal Sustainability and within Multidisciplinary Digital Publishing Institute (MDPI) journals, particularly investigating self‐citations at journal and publisher levels. I analysed articles published by Sustainability in 2015 and found that self‐citations are higher than expected under a uniform probability distribution. Self‐citations in this journal make a 36% difference to the journal's impact factor. This research raises the question of what citation patterns can be expected as normal, and where the boundary between normal and anomaly lies. I suggest the issue deserves further investigation because self‐citations have several implications, ranging from impact factors to visibility and influence of scientific journals.  相似文献   

3.
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   

4.
参考文献的评价功能及其对我国学术期刊评价的影响   总被引:50,自引:11,他引:39  
影响因子是一种最直接体现引文关系的期刊评价指标,但是,影响因子是一个相对的概念,有一定的局限性:由于一论文发表的时滞和研究时期不同、引文峰出现的时间不同、期刊源不同以及期刊自引现象等这些不确定因素的影响,经统计和计算得出的影响因子必然不同。这些都决定了利用参考文献的评价功能所得到的期刊评价指标只能是一种参考性的评价指标,所以构建科学的学术类科技期刊的评价体系已势在必行。  相似文献   

5.
期刊学术影响力、期刊对稿件的录用标准和期刊载文的学术影响力三者之间存在同向加强的机制,来自较高影响力期刊的引用具有较高的评价意义。作者的择刊引用和择刊发表使得较低学术影响力的期刊较少被较高影响力期刊引用。因而,可以通过同时考察构成期刊引证形象的施引期刊的学术影响力及其施引频次来评价被引期刊的学术影响力。以综合性期刊Nature和Science 2010年的引证形象为例,将期刊影响因子作为学术影响力的初评结果,提出了以施引频次对施引期刊影响因子加权的计算方法,以期通过量化的引证形象实现对期刊的评价。  相似文献   

6.
SCI的引文统计指标及其与研究评价的关系   总被引:16,自引:1,他引:15  
从引证类型和检索系统统计源期刊组成分析SCI的引文统计数据及相关指标与期刊和论文学术水平间的不对应关系,并从引文统计时段、论文类型和期刊大小等方面探讨影响因子本身的不确定性;通过分析中国科技期刊的被引情况指出SCI中引文数据的统计错误。认为在我国的科研成果和学术期刊评价中,一定要具体分析SCI的统计数据,适度、合理地使用引证分析方法。  相似文献   

7.
OBJECTIVE: To quantify the impact of Pakistani Medical Journals using the principles of citation analysis. METHODS: References of articles published in 2006 in three selected Pakistani medical journals were collected and examined. The number of citations for each Pakistani medical journal was totalled. The first ranking of journals was based on the total number of citations; second ranking was based on impact factor 2006 and third ranking was based on the 5-year impact factor. Self-citations were excluded in all the three ratings. RESULTS: A total of 9079 citations in 567 articles were examined. Forty-nine separate Pakistani medical journals were cited. The Journal of the Pakistan Medical Association remains on the top in all three rankings, while Journal of College of Physicians and Surgeons-Pakistan attains second position in the ranking based on the total number of citations. The Pakistan Journal of Medical Sciences moves to second position in the ranking based on the impact factor 2006. The Journal of Ayub Medical College, Abbottabad moves to second position in the ranking based on the 5-year impact factor. CONCLUSION: This study examined the citation pattern of Pakistani medical journals. The impact factor, despite its limitations, is a valid indicator of quality for journals.  相似文献   

8.
如何提高英文版科技期刊的被引频次和影响因子   总被引:3,自引:0,他引:3  
蔡斐 《编辑学报》2005,17(2):133-134
从总被引频次和影响因子2方面分析我国英文版科技期刊的引用指标的现状和引用指标偏低的原因.提出了提高英文版科技期刊被引频次和影响因子的措施:1)注重期刊的国内外发行工作;2)通过建立英文网站及加入国内外知名数据库,提高文章的点击率及浏览量;3)请专家把语言关.  相似文献   

9.
[目的/意义]探讨被引频次位置指标在科技期刊评价中的作用,确定合适时间窗口的最优位置指标。[方法/过程]从Web of Science数据库中选取符合条件的14种眼科期刊作为研究对象,分别计算各期刊2014年度不同位置指标,包括2年、5年、8年和10年引证时间窗口(citation time window,CTW)的h指数(h2、h5、h8和h10)、累计h指数(a-h2、a-h5、a-h8和a-h10)以及相对应的期刊2014年度被引频次百分位数位置(percentage rank position,PRP)指标(Top1%、Top5%、Top10%、Top25%Top50%)和累计PRP指标(a-Top1%、a-Top5%、a-Top10%、a-Top25%和a-Top50%)。比较影响因子、不同CTW位置指标与期刊问卷调查评分的相关度,确定不同位置指标应用于期刊评价的效果。[结果/结论]合理的位置指标在期刊影响力评价中优于影响因子和5年影响因子,累计被引频次位置指标普遍优于年度指标,2年CTW的h指数优于其他CTW的h指数,5年CTW的a-h2、h2,5年和8年CTW的a-Top50%和Top50%与影响因子和5年影响因子相比具有更理想的期刊评价效果。  相似文献   

10.
Although there are at least six dimensions of journal quality, Beall's List identifies predatory Open Access journals based almost entirely on their adherence to procedural norms. The journals identified as predatory by one standard may be regarded as legitimate by other standards. This study examines the scholarly impact of the 58 accounting journals on Beall's List, calculating citations per article and estimating CiteScore percentile using Google Scholar data for more than 13,000 articles published from 2015 through 2018. Most Beall's List accounting journals have only modest citation impact, with an average estimated CiteScore in the 11th percentile among Scopus accounting journals. Some have a substantially greater impact, however. Six journals have estimated CiteScores at or above the 25th percentile, and two have scores at or above the 30th percentile. Moreover, there is considerable variation in citation impact among the articles within each journal, and high-impact articles (cited up to several hundred times) have appeared even in some of the Beall's List accounting journals with low citation rates. Further research is needed to determine how well the citing journals are integrated into the disciplinary citation network—whether the citing journals are themselves reputable or not.  相似文献   

11.
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   

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.
刘雪立 《编辑学报》2018,30(1):98-101
近年来,期刊影响因子的人为操纵受到学术界广泛关注,期刊过度自引成为人为操纵影响因子的重要手段.期刊自引率是识别影响因子人为操纵的敏感指标,但对小集团内部期刊互引和其他形式人为操纵的识别却无能为力.在该研究中,深度挖掘了自引率、扩散因子、被引半衰期、开放因子和互引指数在期刊影响因子人为操纵识别中的应用.  相似文献   

14.
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   

15.
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   

16.
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   

17.
18.
基于引用期刊质量的影响因子修正法   总被引:1,自引:0,他引:1  
长期以来学术期刊影响因子的计算仅仅统计被引用文章的篇数而没有考虑引用期刊的学术质量,这种计算方法有不尽合理之处.认为在计算影响因子时应充分考虑引用期刊的质量,建议以引用文献的期刊质量为权重对原影响因子公式进行修正.经统计学模拟计算表明,修正后的公式能更客观地对期刊进行评价,这将有利于建立起更公正、合理的期刊评价体系.  相似文献   

19.
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   

20.
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   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号