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1.
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   

2.
As science is becoming more interdisciplinary and potentially more data driven over time, it is important to investigate the changing specialty structures and the emerging intellectual patterns of research fields and domains. By employing a clustering-based network approach, we map the contours of a novel interdisciplinary domain – research using social media data – and analyze how the specialty structures and intellectual contributions are organized and evolve. We construct and validate a large-scale (N = 12,732) dataset of research papers using social media data from the Web of Science (WoS) database, complementing it with citation relationships from the Microsoft Academic Graph (MAG) database. We conduct cluster analyses in three types of citation-based empirical networks and compare the observed features with those generated by null network models. Overall, we find three core thematic research subfields – interdisciplinary socio-cultural sciences, health sciences, and geo-informatics – that designate the main epicenter of research interests recognized by this domain itself. Nevertheless, at the global topological level of all networks, we observe an increasingly interdisciplinary trend over the years, fueled by publications not only from core fields such as communication and computer science, but also from a wide variety of fields in the social sciences, natural sciences, and technology. Our results characterize the specialty structures of this domain at a time of growing emphasis on big social data, and we discuss the implications for indicating interdisciplinarity.  相似文献   

3.
Across the various scientific domains, significant differences occur with respect to research publishing formats, frequencies and citing practices, the nature and organisation of research and the number and impact of a given domain's academic journals. Consequently, differences occur in the citations and h-indices of the researchers. This paper attempts to identify cross-domain differences using quantitative and qualitative measures. The study focuses on the relationships among citations, most-cited papers and h-indices across domains and for research group sizes. The analysis is based on the research output of approximately 10,000 researchers in Slovenia, of which we focus on 6536 researchers working in 284 research group programmes in 2008–2012.As comparative measures of cross-domain research output, we propose the research impact cube (RIC) representation and the analysis of most-cited papers, highest impact factors and citation distribution graphs (Lorenz curves). The analysis of Lotka's model resulted in the proposal of a binary citation frequencies (BCF) distribution model that describes well publishing frequencies. The results may be used as a model to measure, compare and evaluate fields of science on the global, national and research community level to streamline research policies and evaluate progress over a definite time period.  相似文献   

4.
科学-技术关联是指技术创新系统与科学研究系统之间的知识传递关系。探测科学-技术关联的情报学方法是:计量"论文-专利"互引信息,用专利所属的4位IPC类目与论文所属的学科之间的对应关系来反映科学-技术关联。此方法中存在两方面问题:一方面,论文被笼统地视为基础科学的代表,忽略了自然科学体系的"基础科学-技术科学-工程科学"的层级结构;另一方面,IPC类目以"功能"为分类原则且粒度过粗,难以与科学学科合理对应。对科学端的学科层级划分问题和技术端的4位IPC类目细化问题进行研究,对探测科学-技术关联的情报学方法进行改进,并以2006-2009年间的美国催化技术专利和与之具有互引关系的论文为样本进行实验,实验结果反映出更精细的学科-领域对应关系,呈现出更清晰的科学-技术关联图景。  相似文献   

5.
This paper studies the correlations between peer review and citation indicators when evaluating research quality in library and information science (LIS). Forty-two LIS experts provided judgments on a 5-point scale of the quality of research published by 101 scholars; the median rankings resulting from these judgments were then correlated with h-, g- and H-index values computed using three different sources of citation data: Web of Science (WoS), Scopus and Google Scholar (GS). The two variants of the basic h-index correlated more strongly with peer judgment than did the h-index itself; citation data from Scopus was more strongly correlated with the expert judgments than was data from GS, which in turn was more strongly correlated than data from WoS; correlations from a carefully cleaned version of GS data were little different from those obtained using swiftly gathered GS data; the indices from the citation databases resulted in broadly similar rankings of the LIS academics; GS disadvantaged researchers in bibliometrics compared to the other two citation database while WoS disadvantaged researchers in the more technical aspects of information retrieval; and experts from the UK and other European countries rated UK academics with higher scores than did experts from the USA.  相似文献   

6.
Using the dataset based on Thomson Reuters Scientific “Web of Science” the distributions of some well-known indicators, such as h-index and g-index, were investigated, and different citation behaviors across different scientific fields resulting from their field dependences were found. To develop a field-independent index, two scaling methods, based on average citation of subject category and journal, were used to normalize the citation received by each paper of a certain author. The distributions of the generalized h-indices in different fields were found to follow a lognormal function with mean and standard deviation of approximately ?0.8 and 0.8, respectively. A field-independent index fi-index was then proposed, and its distribution was found to satisfy a universal power-law function with scaling exponent α approaching 3.0. Both the power-law and the lognormal universality of the distributions verified the field independence of these indicators. However, deciding which of the scaling methods is the better one is necessary for the validation of the field-independent index.  相似文献   

7.
Greater collaboration generally produces higher category normalised citation impact (CNCI) and more influential science. Citation differences between domestic and international collaborative articles are known, but obscured in analyses of countries’ CNCIs, compromising evaluation insights. Here, we address this problem by deconstructing and distinguishing domestic and international collaboration types to explore differences in article citation rates between collaboration type and countries. Using Web of Science article data covering 2009–2018, we find that individual country citation and CNCI profiles vary significantly between collaboration types (e.g., domestic single institution and international bilateral) and credit counting methods (full and fractional). The ‘boosting’ effect of international collaboration is greatest where total research capacity is smallest, which could mislead interpretation of performance for policy and management purposes. By incorporating collaboration type into the CNCI calculation, we define a new metric labelled Collab-CNCI. This can account for collaboration effects without presuming credit (as fractional counting does). We recommend that analysts should: (1) partition all article datasets so that citation counts can be normalised by collaboration type (Collab-CNCI) to enable improved interpretation for research policy and management; and (2) consider filtering out smaller entities from multinational and multi-institutional analyses where their inclusion is likely to obscure interpretation.  相似文献   

8.
《Journal of Informetrics》2019,13(2):515-539
Counting of number of papers, of citations and the h-index are the simplest bibliometric indices of the impact of research. We discuss some improvements. First, we replace citations with individual citations, fractionally shared among co-authors, to take into account that different papers and different fields have largely different average number of co-authors and of references. Next, we improve on citation counting applying the PageRank algorithm to citations among papers. Being time-ordered, this reduces to a weighted counting of citation descendants that we call PaperRank. We compute a related AuthorRank applying the PageRank algorithm to citations among authors. These metrics quantify the impact of an author or paper taking into account the impact of those authors that cite it. Finally, we show how self- and circular-citations can be eliminated by defining a closed market of Citation-coins. We apply these metrics to the InSpire database that covers fundamental physics, presenting results for papers, authors, journals, institutes, towns, countries for all-time and in recent time periods.  相似文献   

9.
The goal of this analysis was to obtain local citation behavior data on undergraduates researching history, political science, and sociology papers. The study found that students cited books and journals even with the availability of web sources; however, usage varied by subject. References to specific websites' domains also varied across subject area. Most of the top journal titles that students referenced were online and locally owned. Students cited a broader range of journal titles than predicted by the Law of Scattering and cited titles across a wide array of subject areas. This data helped identify potential gaps in the library's collection and services.  相似文献   

10.
We have studied the efficiency of research in the EU by a percentile-based citation approach that analyzes the distribution of country papers among the world papers. Going up in the citation scale, the frequency of papers from efficient countries increases while the frequency from inefficient countries decreases. In the percentile-based approach, this trend, which is uniform at any citation level, is measured by the ep index that equals the Ptop 1%/Ptop 10% ratio. By using the ep index we demonstrate that EU research on fast-evolving technological topics is less efficient than the world average and that the EU is far from being able to compete with the most advanced countries. The ep index also shows that the USA is well ahead of the EU in both fast- and slow-evolving technologies, which suggests that the advantage of the USA over the EU in innovation is due to low research efficiency in the EU. In accord with some previous studies, our results show that the European Commission’s ongoing claims about the excellence of EU research are based on a wrong diagnosis. The EU must focus its research policy on the improvement of its inefficient research. Otherwise, the future of Europeans is at risk.  相似文献   

11.
There is an overall perception of increased interdisciplinarity in science, but this is difficult to confirm quantitatively owing to the lack of adequate methods to evaluate subjective phenomena. This is no different from the difficulties in establishing quantitative relationships in human and social sciences. In this paper we quantified the interdisciplinarity of scientific journals and science fields by using an entropy measurement based on the diversity of the subject categories of journals citing a specific journal. The methodology consisted in building citation networks using the Journal Citation Reports® database, in which the nodes were journals and edges were established based on citations among journals. The overall network for the 11-year period (1999–2009) studied was small-world and followed a power-law with exponential cutoff distribution with regard to the in-strength. Upon visualizing the network topology an overall structure of the various science fields could be inferred, especially their interconnections. We confirmed quantitatively that science fields are becoming increasingly interdisciplinary, with the degree of interdisplinarity (i.e. entropy) correlating strongly with the in-strength of journals and with the impact factor.  相似文献   

12.
This research proposes a new approach that considers citation relevance in main path analysis (MPA). Traditional MPA assumes that all citations have equal weight, but in practice treating every citation equally may not find the main paths that truthfully reflect the knowledge flow in a target science field. To address the issue, this study suggests taking the level of relevance among documents into consideration. For demonstration purposes, the level of relevance is determined by similarity in both citation structure and key phrases among documents. The approach not only achieves convergence of development trajectories, but also helps frame the topics on the main paths to a specific concept from a wide range of research domains. This study takes health interoperability fields as the demonstration case to show the effects of converging the trajectories toward a target domain.  相似文献   

13.
国内图情学者历时h指数研究   总被引：1，自引：0，他引：1  
[目的/意义]针对h指数难以反映学者动态学术影响力问题,为描绘学者不同时段学术影响力动态变化提出附加时间限制的改进指标——历时h指数（TDh指数）。[方法/过程]采集国内图情领域期刊的CSSCI被引数据,采用批量统计法计算全部学者多个时段的TDh指数,以实例论证TDh指数的合理性及应用价值。[结果/结论]TDh指数可描绘学者在学术生涯不同时段的影响力波动情况,研究者可根据不同学术群体的影响力升降情况发现领域新秀及热门研究,并从宏观上观察领域研究主题的兴衰及热点变迁。  相似文献   

14.
刘虹  李煜 《图书情报工作》2018,62(23):87-96
[目的/意义]揭示2002年以来图情领域重要国家在学术论文产出的总量、引证、研究主题、学术合作等维度上的学术贡献与特征演化,为图情领域的学科建设及相关研究者追踪研究主题与前沿提供参考。[方法/过程]以近15年WoS数据库收录的图情领域86种核心期刊为研究对象,应用文献计量学、科学知识图谱、计量模型等研究方法,运用TDA、Ucinet、VOSviewer等数据分析工具,从学术论文的总量特征、引证特征、主题特征三个角度对图情领域重要国家的学术贡献进行深入分析,并构建计量模型考察空间距离及学术能力对重要国家之间学术合作的影响机制。[结果/结论]美国在图情领域的科研实力强劲,中国的学术贡献增速最快,荷兰、芬兰、比利时三国则在归一化被引比率指标上表现突出;研究主题主要集中在图书馆、信息检索、互联网、知识管理、社交网络、计量学、用户研究、研究方法8个主题范畴,英国、西班牙、中国、美国的研究主题最为广泛;空间距离与学术能力都对国家间的学术合作具有显著影响。  相似文献   

15.
Evaluating the performance of institutions with different resources is not easy, any citation distribution comparisons are strongly affected by the differences in the number of articles published. The paper introduces a method for comparing citation distributions of research groups that differ in size. The citation distribution of a larger group is reduced by a certain factor and compared with the original distribution of a smaller group. Expected values and tolerance intervals of the reduced set of citations are calculated. A comparison of both distributions can be conveniently viewed in a graph. The size-independent reduced Hirsch index – a function of reducing factor that allows the comparison of groups within a scientific field – is calculated in the same way. The method can be used for comparing groups or units differing in full-time equivalent, funding or the number of researchers, for comparing countries by population, gross domestic product, etc. It is shown that for the calculation of the reduced Hirsch index, the upper part of the original citation distribution is sufficient. The method is illustrated through several case comparisons.  相似文献   

16.
The history and development of the Science Citation Index (SCI) is an example of the power of users in defining and influencing the development of a new technology. The SCI was developed as a tool for the historian of science for the purpose of tracing the history of ideas, but it was appropriated by users for purposes for which it was unintended – as a tool for evaluating the literature, individuals, institutions, and countries. The development of a citation tool gave rise to a debate over what is actually measured by citations. The citation‐as‐reward camp views citations as indicators of quality and impact, whereas the citation‐as‐persuasion camp views citations as no more than rhetorical devices. While neither view can fully explain how authors use citations, citation‐as‐reward prevails as the dominant interpretation.  相似文献   

17.
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   

18.
In this paper, we propose two methods for scoring scientific output based on statistical quantile plotting. First, a rescaling of journal impact factors for scoring scientific output on a macro level is proposed. It is based on normal quantile plotting which allows to transform impact data over several subject categories to a standardized distribution. This can be used in comparing scientific output of larger entities such as departments working in quite different areas of research. Next, as an alternative to the Hirsch index [Hirsch, J.E. (2005). An index to quantify an individuals scientific research output. Proceedings of the National Academy of Sciences of the United States of America, 102(46), 16569–16572], the extreme value index is proposed as an indicator for assessment of the research performance of individual scientists. In case of Lotkaian–Zipf–Pareto behaviour of citation counts of an individual, the extreme value index can be interpreted as the slope in a Pareto–Zipf quantile plot. This index, in contrast to the Hirsch index, is not influenced by the number of publications but stresses the decay of the statistical tail of citation counts. It appears to be much less sensitive to the science field than the Hirsch index.  相似文献   

19.
[目的/意义]高校实施"双一流"推进学科开放竞争背景下，刻画档案学高被引论文主题结构对于认识档案学科竞争力和图情档学科整体竞争力十分重要。[方法/过程]在述评档案学科竞争力相关研究的基础上，从主题、演化和引用结构方面对档案学CSSCI来源期刊近年的高被引论文统计分析，刻画档案学科结构进而评价总体竞争力。[结果/结论]研究发现：档案学高被引主题集中在档案工作和学科建设领域；档案学理论、档案信息安全、信息技术应用三大主题篇均被引位居前三甲，但总体规模相对不足。上述结果表明，档案学科队伍总体发展相对不均衡，档案学竞争力主要来自于档案工作研究，而对更具竞争力的档案学理论探索和影响学科发展的新兴技术主题研究规模不足。未来提升档案学科竞争力需从增强图情档学科整体竞争力出发，实施统筹划分学科方向并优化学科结构，重构核心领域竞争优势，基于学科融合与开放战略提升档案学理论层次。  相似文献   

20.
科学研究的目的在于创造知识,并应用理论成果解决我国社会、经济、文化等发展中的实际问题。将论文发表在国际期刊上可以让更多的国际同行了解我国最新的科研成果,为我国获得更多的国际影响力,所以在过去二十多年里SCI论文成为我国科研考核的一个重要指标。在这种科研评价导向下,我国学者发表的国际论文数量已居世界第一位,而大量来自国内同行的引用使得我国国际论文的被引量排名世界第二。本文提取1990至2015年Web of Science论文及其引文的数据,分析不同国家、不同学科在国家层次的自引情况,并在不同国家、不同学科之间进行比较。研究发现,在排除国内同行的自引后,我国国际论文的真实国际影响力仍然有限,除了临床医学和物理等少数学科外,其他学科仍然低于全球平均水平。  相似文献   

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