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1.
Modeling a century of citation distributions   总被引：1，自引：1，他引：0  
The prevalence of uncited papers or of highly cited papers, with respect to the bulk of publications, provides important clues as to the dynamics of scientific research. Using 25 million papers and 600 million references from the Web of Science over the 1900–2006 period, this paper proposes a simple model based on a random selection process to explain the “uncitedness” phenomenon and its decline over the years. We show that the proportion of cited papers is a function of (1) the number of articles available (the competing papers), (2) the number of citing papers and (3) the number of references they contain. Using uncitedness as a departure point, we demonstrate the utility of the stretched-exponential function and a form of the Tsallis q-exponential function to fit complete citation distributions over the 20th century. As opposed to simple power-law fits, for instance, both these approaches are shown to be empirically well-grounded and robust enough to better understand citation dynamics at the aggregate level. On the basis of these models, we provide quantitative evidence and provisional explanations for an important shift in citation practices around 1960. We also propose a revision of the “citation classic” category as a set of articles which is clearly distinguishable from the rest of the field.  相似文献   

2.
[目的/意义]探索论文未被引现象是引文分布研究中不可或缺的部分,不仅有利于丰富和扩展计量学的研究范畴,也有利于识别文献未被引的产生机制和最大限度避免科研资源浪费与提升科学交流效率。[方法/过程]以CSSCI为来源数据库,以图书馆情报与文献学为样本学科,随机选择200名学者为样本,获取这些学者的第一作者论文及相关引文数据,以6年为计量时间窗口,依析取的8个外部特征因素计算不同分组的未被引率,采用非参数方法检验各因素是否存在显著差异。[结果/结论]8个外部特征因素对论文未被引都有显著影响,其中作者所属机构的影响相对较小,作者发文时年龄与论文篇幅的影响相对较大,作者发文时职称、作者数量、参考文献数量、关键词数量、基金类别的影响程度大致相仿;各因素的未被引率在前3年的变化较为剧烈,后3年变化较为平缓;各因素未被引率的时间序列变化趋势各不相同,其影响平稳性也变化各异。  相似文献   

3.
《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   

4.
[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   

5.
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   

6.
参考文献的著录质量亟待提高   总被引：14，自引：6，他引：8  
雷琪 《编辑学报》2006,18(1):40-41
指出参考文献著录中存在的9个方面的问题,包括机械式转引,非必要的引用,著录时效性不强,引用非正式文献,引用地域性窄,文献引用过少,不恰当自引,剽窃及文献著录形式上的错误,并提出一些在编辑加工过程中保证参考文献著录质量的措施.  相似文献   

7.
Identifying the future influential papers among the newly published ones is an important yet challenging issue in bibliometrics. As newly published papers have no or limited citation history, linear extrapolation of their citation counts—which is motivated by the well-known preferential attachment mechanism—is not applicable. We translate the recently introduced notion of discoverers to the citation network setting, and show that there are authors who frequently cite recent papers that become highly-cited in the future; these authors are referred to as discoverers. We develop a method for early identification of highly-cited papers based on the early citations from discoverers. The results show that the identified discoverers have a consistent citing pattern over time, and the early citations from them can be used as a valuable indicator to predict the future citation counts of a paper. The discoverers themselves are potential future outstanding researchers as they receive more citations than average.  相似文献   

8.
[目的/意义]引用语境是科学论文中包含引用的句子,是对引文的描述性或评价性文字。通过提取和分析引用语境中的线索词,可以了解引用语境的一般特征。[方法/过程]以Journal of Informetrics（JOI）期刊为例,选取人称代词、行为动词和连接词三类常用的线索词,分别计算它们在引用语境中的频次、占比和排序。通过比较各类线索词在引用语境和非引用语境中的存在度,识别引用语境中的常用句型和论证模式。[结果/结论]在JOI期刊中,引用语境主要表现出如下特点：侧重于第一人称和第三人称论述,既展现他人的工作,也展现作者的研究;偏重于研究方法类引用,常用的行为动词为"use"base"和"study";强调通过转折和列举等逻辑方式进行论证,最常用的连接词位"also"和"but"。分析引用语境中的线索词,对于更好地理解科学论文中的引用的功能和动机具有重要的价值和意义。  相似文献   

9.
Traditionally, citation count has served as the main evaluation measure for a paper's importance and influence. In turn, many evaluations of authors, institutions and journals are based on aggregations upon papers (e.g. h-index). In this work, we explore measures defined on the citation graph that offer a more intuitive insight into the impact of a paper than the superficial count of citations. Our main argument is focused on the identification of influence as an expression of the citation density in the subgraph of citations built for each paper. We propose two measures that capitalize on the notion of density providing researchers alternative evaluations of their work. While the general idea of impact for a paper can be viewed as how many researchers have shown interest to a piece of work, the proposed measures are based on the hypothesis that a piece of work may have influenced some papers even if they do not contain references to that piece of work. The proposed measures are also extended to researchers and journals.  相似文献   

10.
Demonstrating the practical value of public research has been an important subject in science policy. Here we present a detailed study on the evolution of the citation linkage between life science related patents and biomedical research over a 37-year period. Our analysis relies on a newly-created dataset that systematically links millions of non-patent references to biomedical papers. We find a large disparity in the volume of citations to science among technology sectors, with biotechnology and drug patents dominating it. The linkage has been growing exponentially over a long period of time, doubling every 2.9 years. The U.S. has been the largest producer of cited science for years, receiving nearly half of the citations. More than half of citations goes to universities. We use a new paper-level indicator to quantify to what extent a paper is basic research or clinical medicine. We find that the cited papers are likely to be basic research, yet a significant portion of papers cited in patents that are related to FDA-approved drugs are clinical research. The U.S. National Institute of Health continues to be an important funder of cited science. For the majority of companies, more than half of citations in their patents are authored by public research. Taken together, these results indicate a continuous linkage of public science to private sector inventions.  相似文献   

11.
The findings of Bornmann, Leydesdorff, and Wang (2013b) revealed that the consideration of journal impact improves the prediction of long-term citation impact. This paper further explores the possibility of improving citation impact measurements on the base of a short citation window by the consideration of journal impact and other variables, such as the number of authors, the number of cited references, and the number of pages. The dataset contains 475,391 journal papers published in 1980 and indexed in Web of Science (WoS, Thomson Reuters), and all annual citation counts (from 1980 to 2010) for these papers. As an indicator of citation impact, we used percentiles of citations calculated using the approach of Hazen (1914). Our results show that citation impact measurement can really be improved: If factors generally influencing citation impact are considered in the statistical analysis, the explained variance in the long-term citation impact can be much increased. However, this increase is only visible when using the years shortly after publication but not when using later years.  相似文献   

12.
Delayed recognition is a concept applied to articles that receive very few to no citations for a certain period of time following publication, before becoming actively cited. To determine whether such a time spent in relative obscurity had an effect on subsequent citation patterns, we selected articles that received no citations before the passage of ten full years since publication, investigated the subsequent yearly citations received over a period of 37 years and compared them with the citations received by a group of papers without such a latency period. Our study finds that papers with delayed recognition do not exhibit the typical early peak, then slow decline in citations, but that the vast majority enter decline immediately after their first – and often only – citation. Middling papers’ citations remain stable over their lifetime, whereas the more highly cited papers, some of which fall into the “sleeping beauty” subtype, show non-stop growth in citations received. Finally, papers published in different disciplines exhibit similar behavior and did not differ significantly.  相似文献   

13.
In this study, we investigate the extent to which patent citations to papers can serve as early signs for predicting delayed recognized knowledge in science using a comparative study with a control group, i.e., instant recognition papers. We identify the two opposite groups of papers by the Bcp measure, a parameter-free index for identifying papers which were recognized with delay. We provide a macro (Science/Nature papers dataset) and micro (a case chosen from the dataset) evidence on paper-patent citation linkages as early signs for predicting delayed recognized knowledge in science. It appears that papers with delayed recognition show a stronger and longer technical impact than instant recognition papers. We provide indication that in the more recent years papers with delayed recognition are awakened more often and earlier by a patent rather than by a scientific paper (also called “prince”). We also found that patent citations seem to play an important role to avoid instant recognition papers to level off or to become a so called “flash in the pan”, i.e., instant recognition. It also appears that the sleeping beauties may firstly encounter negative citations and then patent citations and finally get widely recognized. In contrast to the two focused fields (biology and chemistry) for instant recognition papers, delayed recognition papers are rather evenly distributed in biology, chemistry, psychology, geology, materials science, and physics. We discovered several pairs of “science sleeping”-“technology inducing”, such as “biology-biotechnology/pharmaceuticals”, “chemistry-chemical engineering”, as well as some trans-fields science-technology interactions, such as “psychology - computer technology/control technology/audio-visual technology”, “physics - computer technology”, and “mathematics-computer technology”. We propose in further research to discover the potential ahead of time and transformative research by using citation delay analysis, patent & NPL analysis, and citation context analysis.  相似文献   

14.
参考文献著录中的学术道德缺失现象及其防范   总被引：15，自引：4，他引：11  
郭玲  陈燕 《编辑学报》2007,19(1):8-10
在参考文献著录中存在着诸多问题,其中一些属于无意识过错,还有一些由于主观原因有意识地采取非正当或超过学术道德范畴的不良手段,主要包括引而不著、著而不引、过度他引、不正当自引、模糊著引等.为了防范参考文献著录中的学术道德缺失,编辑必须做好把关人,并从自律与他律等方面加以遏制.  相似文献   

15.
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   

16.
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   

17.
[目的/意义]从内容差异来探索论文未被引规律,不仅是论文未被引现象研究的重要内容,也有利于扩展基于内容的引文分析方法范畴。[方法/过程]以CSSCI作为来源数据库,以图书馆情报与文献学为样本学科,依据该学科学者的h指数分布特征随机选择200名学者作为样本对象,下载其1998-2015年的所有被收录论文数据;下载样本学科1998-2015年的所有收录论文数据,并离析出对应被引论文、高被引论文的相关数据;以6年为时间窗口,将发表后1-3年内被引的论文定义为被引论文,其余的为未被引论文;析取未被引论文、被引论文、学科整体论文及高被引论文的关键词,按关键词频数从高到低排序,选取排序前50的关键词构成关键词向量,计算关键词向量的内积、欧几里得长度和余弦相似度。[结果/结论]图书馆情报与文献学领域在21世纪初形成较为稳定的研究内容体系,其未被引论文与学科整体论文、被引论文、高被引论文的内容相似度都较低,表明研究内容对论文未被引有重要影响。  相似文献   

18.
The non-citation rate refers to the proportion of papers that do not attract any citation over a period of time following their publication. After reviewing all the related papers in Web of Science, Google Scholar and Scopus database, we find the current literature on citation distribution gives more focus on the distribution of the percentages and citations of papers receiving at least one citation, while there are fewer studies on the time-dependent patterns of the percentage of never-cited papers, on what distribution model can fit their time-dependent patterns, as well as on the factors influencing the non-citation rate. Here, we perform an empirical pilot analysis to the time-dependent distribution of the percentages of never-cited papers in a series of different, consecutive citation time windows following their publication in our selected six sample journals, and study the influence of paper length on the chance of papers’ getting cited. Through the above analysis, the following general conclusions are drawn: (1) a three-parameter negative exponential model can well fit time-dependent distribution curve of the percentages of never-cited papers; (2) in the initial citation time window, the percentage of never-cited papers in each journal is very high. However, as the citation time window becomes wider and wider, the percentage of never-cited papers begins to drop rapidly at first, and then drop more slowly, and the total degree of decline for most of journals is very large; (3) when applying the wider citation time windows, the percentage of never-cited papers for each journal begins to approach a stable value, and after that value, there will be very few changes in these stable percentages, unless we meet a large amount of “Sleeping Beauties” type papers; (4) the length of an paper has a great influence on whether it will be cited or not.  相似文献   

19.
[目的/意义]探索中文学术期刊论文的引文模式及时间窗口的选择对引文模式的影响，建立引文模式的分析框架。[方法/过程]以2006-2008年出版的图书情报领域期刊论文作为研究对象，采用两步聚类法对单篇论文在7年内的绝对被引量与相对被引量进行聚类分析，研究论文主要特征因子与引文模式的相关性。[结果/结论]在绝对被引量视角下，期刊论文均表现为先上升后下降的经典引文模式；在相对下载量视角下，期刊论文共有6种引文模式，其中3种可以归纳为经典引文模式，另外3种分别为"类睡美人型"、正偏型和马拉松型。相对被引量视角下，首年被引量与总被引量呈现了中等甚至较强的相关性，并且平均被引量越高，相关性越强，绝对被引量视角下的结果正好相反。结果表明，期刊论文的初始被引量与总被引量的相关性高低主要取决于引文曲线的峰度而非总被引量的大小。  相似文献   

20.
《编辑学报》高被引论文分析   总被引：5，自引：1，他引：4  
张建合 《编辑学报》2010,22(6):562-564
以中国知网<中国学术文献网络出版总库>为统计源,从文献引证的角度分析<编辑学报>高被引论文的分布规律.研究结果表明:该数据库共收录<编辑学报>1989-2009年原文3 508篇,被引文献2545篇,被引率为73%,总被引频次为1万5 863,单篇最高被引频次71;较少的论文拥有较高的被引频次,基本符合"二八定律";前100篇高被引论文中,栏目高被引论文数最多的是<理论研究>(46篇),个人高被引论文数最多的是游苏宁(6篇);前10篇高被引论文每年都在被引用,具有旺盛的生命力.  相似文献   

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