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Multidisciplinary cooperation is now common in research since social issues inevitably involve multiple disciplines. In research articles, reference information, especially citation content, is an important representation of communication among different disciplines. Analyzing the distribution characteristics of references from different disciplines in research articles is basic to detecting the sources of referred information and identifying contributions of different disciplines. This work takes articles in PLoS as the data and characterizes the references from different disciplines based on Citation Content Analysis (CCA). First, we download 210,334 full-text articles from PLoS and collect the information of the in-text citations. Then, we identify the discipline of each reference in these academic articles. To characterize the distribution of these references, we analyze three characteristics, namely, the number of citations, the average cited intensity and the average citation length. Finally, we conclude that the distributions of references from different disciplines are significantly different. Although most references come from Natural Science, Humanities and Social Sciences play important roles in the Introduction and Background sections of the articles. Basic disciplines, such as Mathematics, mainly provide research methods in the articles in PLoS. Citations mentioned in the Results and Discussion sections of articles are mainly in-discipline citations, such as citations from Nursing and Medicine in PLoS.  相似文献   

3.
We address issues concerning what one may learn from how citation instances are distributed in scientific articles. We visualize and analyze patterns of citation distributions in the full text of 350 articles published in the Journal of Informetrics. In particular, we visualize and analyze the distributions of citations in articles that are organized in a commonly seen four-section structure, namely, introduction, method, results, and conclusions (IMRC). We examine the locations of citations to the groundbreaking h-index paper by Hirsch in 2005 and how patterns associated with citation locations evolve over time. The results show that citations are highly concentrated in the first section of an article. The density of citations in the first section is about three times higher than that in subsequent sections. The distributions of citations to highly cited papers are even more uneven.  相似文献   

4.
In citation network analysis, complex behavior is reduced to a simple edge, namely, node A cites node B. The implicit assumption is that A is giving credit to, or acknowledging, B. It is also the case that the contributions of all citations are treated equally, even though some citations appear multiply in a text and others appear only once. In this study, we apply text-mining algorithms to a relatively large dataset (866 information science articles containing 32,496 bibliographic references) to demonstrate the differential contributions made by references. We (1) look at the placement of citations across the different sections of a journal article, and (2) identify highly cited works using two different counting methods (CountOne and CountX). We find that (1) the most highly cited works appear in the Introduction and Literature Review sections of citing papers, and (2) the citation rankings produced by CountOne and CountX differ. That is to say, counting the number of times a bibliographic reference is cited in a paper rather than treating all references the same no matter how many times they are invoked in the citing article reveals the differential contributions made by the cited works to the citing paper.  相似文献   

5.
Wide differences in publication and citation practices make impossible the direct comparison of raw citation counts across scientific disciplines. Recent research has studied new and traditional normalization procedures aimed at suppressing as much as possible these disproportions in citation numbers among scientific domains. Using the recently introduced IDCP (Inequality due to Differences in Citation Practices) method, this paper rigorously tests the performance of six cited-side normalization procedures based on the Thomson Reuters classification system consisting of 172 sub-fields. We use six yearly datasets from 1980 to 2004, with widely varying citation windows from the publication year to May 2011. The main findings are the following three. Firstly, as observed in previous research, within each year the shapes of sub-field citation distributions are strikingly similar. This paves the way for several normalization procedures to perform reasonably well in reducing the effect on citation inequality of differences in citation practices. Secondly, independently of the year of publication and the length of the citation window, the effect of such differences represents about 13% of total citation inequality. Thirdly, a recently introduced two-parameter normalization scheme outperforms the other normalization procedures over the entire period, reducing citation disproportions to a level very close to the minimum achievable given the data and the classification system. However, the traditional procedure of using sub-field mean citations as normalization factors yields also good results.  相似文献   

6.
The distribution of cumulative citations L and contributed citations Lf to individual multiauthored papers published by selected authors working in different scientific disciplines is analyzed and discussed using Langmuir-type function: yn = y0[1  αKn/(1 + Kn)], where yn denotes the total number of normalized cumulative citations ln* and normalized contributed citations lnf* received by individual papers of rank n, y0 is the maximum value of yn when n = 0, α  1 is an effectiveness parameter, and K is the Langmuir constant related to the dimensionless differential energy Q = ln(KNc), with Nc as the number of papers receiving citations. Relationships between the values of the Langmuir constant K of the distribution function, the number Nc of papers of an individual author receiving citations and the effectiveness parameter α of this function, obtained from analysis of the data of rank-size distributions of the authors, are investigated. It was found that: (1) the quantity KNc obtained from the real citation distribution of papers of various authors working in different disciplines is inversely proportional to (α  1) with a proportional constant (KNc)0 < 1, (2) the relation KNc = (KNc)0/(α  1) also holds for the citation distribution of journals published in countries of two different groups, investigated earlier (Sangwal, K. (2013). Journal of Informetrics, 7, 487–504), and (3) deviations of the real citation distribution from curves predicted by the Langmuir-type function are associated with changing activity of sources of generation of items (citations).  相似文献   

7.
Reliable methods for the assessment of research success are still in discussion. One method, which uses the likelihood of publishing very highly cited papers, has been validated in terms of Nobel prizes garnered. However, this method cannot be applied widely because it uses the fraction of publications in the upper tail of citation distribution that follows a power law, which includes a low number of publications in most countries and institutions. To achieve the same purpose without restrictions, we have developed the double rank analysis, in which publications that have a low number of citations are also included. By ranking publications by their number of citations from highest to lowest, publications from institutions or countries have two ranking numbers: one for their internal and another one for world positions; the internal ranking number can be expressed as a function of the world ranking number. In log–log double rank plots, a large number of publications fit a straight line; extrapolation allows estimating the likelihood of publishing the highest cited publication. The straight line derives from a power law behavior of the double rank that occurs because citations follow lognormal distributions with values of μ and σ that vary within narrow limits.  相似文献   

8.
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   

9.
哪些因素会影响学术论文的被引次数是文献计量学领域的一个经典研究议题。目前的研究主要关注论文的内容特征和形式特征与被引次数之间的关系,鲜有研究从文本可读性视角切入这一议题。文本可读性影响读者对文本内容的理解和知识吸收,是一个关乎知识传播效率和研究成果认可度的重要因素。本研究在控制论文知识品质和权威性的基础上,使用文本可读性R值等五个变量研究论文的文本可读性对被引次数的影响。以中文图书情报学知名期刊发表于2016—2020年的论文为研究样本,研究发现论文的文本可读性R值、是否采用复合式标题、是否使用公式和表格对被引次数有显著影响,而是否使用图对被引次数没有显著影响。研究验证了中文情境下文本可读性对论文影响力的实质性作用,研究结果对科研人员改善自身的中文学术写作以及提高研究成果影响力具有重要参考价值。  相似文献   

10.
Abstract

Citation management programs are tools used to organize references and to create citations and bibliographies. Libraries are often the central point for providing training and support in using these tools. To determine how we could improve our support and training services, we surveyed users to determine what software in being used, why they chose that particular program, what features are important, and how they use citation management programs to collaborate. Results indicate that users chose a particular program because it was freely available or recommended to them by others and that they thought that importing references and creating citations were important features. We also found a majority of respondents used citation management programs to collaborate and turned to the library for training and support.  相似文献   

11.
学术研究过程中的文献阅读和论文撰写与参考文献标注方法密切相关.在阅读文献时,著者-出版年制更符合阅读习惯,有更多的有效信息含量,更有助于提高阅读和学习效率.在撰写和修改论文时,著者-出版年制能更便利地处理参考文献,提高引文的准确性.  相似文献   

12.
Articles are cited for different purposes and differentiating between reasons when counting citations may therefore give finer-grained citation count information. Although identifying and aggregating the individual reasons for each citation may be impractical, recording the number of citations that originate from different article sections might illuminate the general reasons behind a citation count (e.g., 110 citations = 10 Introduction citations + 100 Methods citations). To help investigate whether this could be a practical and universal solution, this article compares 19 million citations with DOIs from six different standard sections in 799,055 PubMed Central open access articles across 21 out of 22 fields. There are apparently non-systematic differences between fields in the most citing sections and the extent to which citations from one section overlap with citations from another, with some degree of overlap in most cases. Thus, at a science-wide level, section headings are partly unreliable indicators of citation context, even if they are more standard within individual fields. They may still be used within fields to help identify individual highly cited articles that have had one type of impact, especially methodological (Methods) or context setting (Introduction), but expert judgement is needed to validate the results.  相似文献   

13.
This study assesses whether eleven factors associate with higher impact research: individual, institutional and international collaboration; journal and reference impacts; abstract readability; reference and keyword totals; paper, abstract and title lengths. Authors may have some control over these factors and hence this information may help them to conduct and publish higher impact research. These factors have been previously researched but with partially conflicting findings. A simultaneous assessment of these eleven factors for Biology and Biochemistry, Chemistry and Social Sciences used a single negative binomial-logit hurdle model estimating the percentage change in the mean citation counts per unit of increase or decrease in the predictor variables. The journal Impact Factor was found to significantly associate with increased citations in all three areas. The impact and the number of cited references and their average citation impact also significantly associate with higher article citation impact. Individual and international teamwork give a citation advantage in Biology and Biochemistry and Chemistry but inter-institutional teamwork is not important in any of the three subject areas. Abstract readability is also not significant or of no practical significance. Among the article size features, abstract length significantly associates with increased citations but the number of keywords, title length and paper length are insignificant or of no practical significance. In summary, at least some aspects of collaboration, journal and document properties significantly associate with higher citations. The results provide new and particularly strong statistical evidence that the authors should consider publishing in high impact journals, ensure that they do not omit relevant references, engage in the widest possible team working, when appropriate, and write extensive abstracts. A new finding is that whilst is seems to be useful to collaborate and to collaborate internationally, there seems to be no particular need to collaborate with other institutions within the same country.  相似文献   

14.
Characteristic scores and scales (CSS) – a well-established scientometric tool for the study of citation counts – have been used to document a striking phenomenon that characterizes citation distributions at high levels of aggregation: irrespective of scientific field and citation window empirical studies find a persistent pattern whereby about 70% of scientific papers belong to the class of poorly cited papers, about 21% belong to the class of fairly cited papers, 6% to that of remarkably cited papers and 3% to the class of outstandingly cited papers. This article aims to advance the understanding of this remarkable result by examining it in the context of the lognormal distribution, a popular model used to describe citation counts across scientific fields. The article shows that the application of the CSS method to lognormal distributions provides a very good fit to the 70–21–6–3% empirical pattern provided these distributions are characterized by a standard deviation parameter in the range of about 0.8–1.3. The CSS pattern is essentially explainable as an epiphenomenon of the lognormal functional form and, more generally, as a consequence of the skewness of science which is manifest in heavy-tailed citation distributions.  相似文献   

15.
This study provides a conceptual overview of the literature dealing with the process of citing documents (focusing on the literature from the recent decade). It presents theories, which have been proposed for explaining the citation process, and studies having empirically analyzed this process. The overview is referred to as conceptual, because it is structured based on core elements in the citation process: the context of the cited document, processes from selection to citation of documents, and the context of the citing document. The core elements are presented in a schematic representation. The overview can be used to find answers on basic questions about the practice of citing documents. Besides understanding of the process of citing, it delivers basic information for the proper application of citations in research evaluation.  相似文献   

16.
Scholarly citations – widely seen as tangible measures of the impact and significance of academic papers – guide critical decisions by research administrators and policy makers. The citation distributions form characteristic patterns that can be revealed by big-data analysis. However, the citation dynamics varies significantly among subject areas, countries etc. The problem is how to quantify those differences, separate global and local citation characteristics. Here, we carry out an extensive analysis of the power-law relationship between the total citation count and the h-index to detect a functional dependence among its parameters for different science domains. The results demonstrate that the statistical structure of the citation indicators admits representation by a global scale and a set of local exponents. The scale parameters are evaluated for different research actors – individual researchers and entire countries – employing subject- and affiliation-based divisions of science into domains. The results can inform research assessment and classification into subject areas; the proposed divide-and-conquer approach can be applied to hidden scales in other power-law systems.  相似文献   

17.
《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   

18.
The rise of software as a research object is mirrored by increasing interests in quantitative studies of scientific software. However, inconsistent citation practices have led most existing studies of this type to base their analysis of software impact on software name mentions, as identified in full-text publications. Despite its limitations, citation data exists in much greater quantities and covers a broader array of scientific fields than full-text data, and thus can support investigations with much wider scope. This paper aims to analyze the extent to which citation data can be used to reconstruct the impact of software. Specifically, we identify the variety of citable objects related to the lme4 R package and examine how the package’s impact is dispersed across these objects. Our results shed light on a little-discussed challenge of using citation data to measure software impact: even within the category of formal citation, the same software object might be cited in different forms. We consider the implications of this challenge and propose a method to reconstruct the impact of lme4 through its citations nonetheless.  相似文献   

19.
The citations to a set of academic articles are typically unevenly shared, with many articles attracting few citations and few attracting many. It is important to know more precisely how citations are distributed in order to help statistical analyses of citations, especially for sets of articles from a single discipline and a small range of years, as normally used for research evaluation. This article fits discrete versions of the power law, the lognormal distribution and the hooked power law to 20 different Scopus categories, using citations to articles published in 2004 and ignoring uncited articles. The results show that, despite its popularity, the power law is not a suitable model for collections of articles from a single subject and year, even for the purpose of estimating the slope of the tail of the citation data. Both the hooked power law and the lognormal distributions fit best for some subjects but neither is a universal optimal choice and parameter estimates for both seem to be unreliable. Hence only the hooked power law and discrete lognormal distributions should be considered for subject-and-year-based citation analysis in future and parameter estimates should always be interpreted cautiously.  相似文献   

20.
[目的/意义]在学术交流日趋国际化的背景下,本文拟探索引文国际化与被引量之间的关系,力图回答良好的国际视野是否有助于提升论文的学术影响力这一学界普遍关注的问题。[研究设计/方法]以社会科学为研究对象,选取管理学、图书情报学和新闻传播学的181,406篇CSSCI论文为研究样本,采用相关分析、非参数检验与回归分析的方法研究引用外文期刊论文的数量、学术质量、学科领域、时效性对论文被引量的影响。[结论/发现]在控制了文献类型、期刊声誉等若干可能影响论文被引量的因素后,发现样本论文的引文国际化水平对其被引量具有显著的正向影响。具体而言,引用外文期刊论文的数量越多、平均学术质量越高、学科专属度越高、平均时效性越强的论文具有更高的被引量。[创新/价值]证实了国际视野有助于提升中文社科论文的学术影响力,并提出了有针对性的建议。  相似文献   

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