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1.
In the double rank analysis of research publications, the local rank position of a country or institution publication is expressed as a function of the world rank position. Excluding some highly or lowly cited publications, the double rank plot fits well with a power law, which can be explained because citations for local and world publications follow lognormal distributions. We report here that the distribution of the number of country or institution publications in world percentiles is a double rank distribution that can be fitted to a power law. Only the data points in high percentiles deviate from it when the local and world μ parameters of the lognormal distributions are very different. The likelihood of publishing very highly cited papers can be calculated from the power law that can be fitted either to the upper tail of the citation distribution or to the percentile-based double rank distribution. The great advantage of the latter method is that it has universal application, because it is based on all publications and not just on highly cited publications. Furthermore, this method extends the application of the well-established percentile approach to very low percentiles where breakthroughs are reported but paper counts cannot be performed.  相似文献   

2.
The relationship between researchers’ publishing and citing behaviours has received little examination despite its potential importance in scholarly communication, particularly at an international level. To remedy this we studied documents and their references indexed in Thomson Reuters's Web of Science (WoS) in the period 2000–2009 to compare journal publishing behaviours against journal citing behaviours across the world. The results reveal that most publications in, and citations to, all five quality based strata of journals examined come from scientifically and economically advanced countries. Nevertheless, in proportion to their total number of citations given to WoS journals, it seems that less developed countries cite high-quality journals at the same rate as developed countries and so the poorer publishing of less developed countries does not seem to be due to a lack of access to top journals. Moreover, examining the publishing and citing trends of countries revealed a decreasing rate of high-income and Scientifically Advanced Countries (SACs) publications in, and citations to, all quality ranges of journals in comparison to the increasing rate of publications and citations of other groups. Finally, research cooperation between developed and less developed countries seems to positively influence the publishing behaviour of the latter as their publications co-authored with developed countries were published more often in top journals.  相似文献   

3.
We show that usually the influence on the Hirsch index of missing highly cited articles is much smaller than the number of missing articles. This statement is shown by a combinatorial argument. We further show, by using a continuous power law model, that the influence of missing articles is largest when the total number of publications is small, and non-existing when the number of publications is very large. The same conclusion can be drawn for missing citations. Hence, the h-index is resilient to missing articles and to missing citations.  相似文献   

4.
It is widely accepted that data is fundamental for research and should therefore be cited as textual scientific publications. However, issues like data citation, handling and counting the credit generated by such citations, remain open research questions.Data credit is a new measure of value built on top of data citation, which enables us to annotate data with a value, representing its importance. Data credit can be considered as a new tool that, together with traditional citations, helps to recognize the value of data and its creators in a world that is ever more depending on data.In this paper we define data credit distribution (DCD) as a process by which credit generated by citations is given to the single elements of a database. We focus on a scenario where a paper cites data from a database obtained by issuing a query. The citation generates credit which is then divided among the database entities responsible for generating the query output. One key aspect of our work is to credit not only the explicitly cited entities, but even those that contribute to their existence, but which are not accounted in the query output.We propose a data credit distribution strategy (CDS) based on data provenance and implement a system that uses the information provided by data citations to distribute the credit in a relational database accordingly.As use case and for evaluation purposes, we adopt the IUPHAR/BPS Guide to Pharmacology (GtoPdb), a curated relational database. We show how credit can be used to highlight areas of the database that are frequently used. Moreover, we also underline how credit rewards data and authors based on their research impact, and not merely on the number of citations. This can lead to designing new bibliometrics for data citations.  相似文献   

5.
To take into account the impact of the different bibliometric features of scientific fields and different size of both the publication set evaluated and the set used as reference standard, two new impact indicators are introduced. The Percentage Rank Position (PRP) indicator relates the ordinal rank position of the article assessed to the total number of papers in the publishing journal. The publications in the publishing journal are ranked by the decreasing citation frequency. The Relative Elite Rate (RER) indicator relates the number of citations obtained by the article assessed to the mean citation rate of the papers in the elite set of the publishing journal. The indices can be preferably calculated from the data of the publications in the elite set of journal papers of individuals, teams, institutes or countries. The number of papers in the elite set is calculated by the equation: P(πv) = (10 log P) ? 10, where P is the total number of papers. The mean of the PRP and RER indicators of the journal papers assessed may be applied for comparing the eminence of publication sets across fields.  相似文献   

6.
The arbitrariness of the h-index becomes evident, when one requires q × h instead of h citations as the threshold for the definition of the index, thus changing the size of the core of the most influential publications of a dataset. I analyze the citation records of 26 physicists in order to determine how much the prefactor q influences the ranking. Likewise, the arbitrariness of the highly-cited-publications indicator is due to the threshold value, given either as an absolute number of citations or as a percentage of highly cited papers. The analysis of the 26 citation records shows that the changes in the rankings in dependence on these thresholds are rather large and comparable with the respective changes for the h-index.  相似文献   

7.
From the way that it was initially defined (Hirsch, 2005), the h-index naturally encourages focus on the most highly cited publications of an author and this in turn has led to (predominantly) a rank-based approach to its investigation. However, Hirsch (2005) and Burrell (2007a) both adopted a frequency-based approach leading to general conjectures regarding the relationship between the h-index and the author's publication and citation rates as well as his/her career length. Here we apply the distributional results of Burrell, 2007a, Burrell, 2013b to three published data sets to show that a good estimate of the h-index can often be obtained knowing only the number of publications and the number of citations. (Exceptions can occur when an author has one or more “outliers” in the upper tail of the citation distribution.) In other words, maybe the main body of the distribution determines the h-index, not the wild wagging of the tail. Furthermore, the simple geometric distribution turns out to be the key.  相似文献   

8.
This article analyzes the bibliometric features (the number of pages, completion years, the fields of subject, the number of citations, and their distribution by types of sources and years) of 100 theses and dissertations completed at the Department of Librarianship of Hacettepe University between 1974 and 2002. Almost a quarter (24%) of all dissertations were on university libraries, followed by public libraries (9%). Doctoral dissertations were, on average, twice as long as master's theses and contained 2.5 times more citations. Monographs received more citations (50%) than journal articles did (42%). Recently completed theses and dissertations contained more citations to electronic publications. Fourteen (or 3.2% of all) journal titles (including Türk Kütüphaneciliği, College & Research Libraries, and Journal of the American Society for Information Science) received almost half (48.9%) of all citations. Eighty percent of journal titles were cited infrequently. No correlation was found between the frequency of citations of the most frequently cited journals and their impact factors. Cited journal titles in master's and doctoral theses and dissertations overlapped significantly. Similarly, journal titles cited in dissertations also overlapped significantly with those that were cited in the journal articles published in the professional literature. The distribution of citations to foreign journal titles fit Bradford's Law of Scattering. The mean half-life of all cited sources was 9 years. Sources cited in master's dissertations were relatively more current. Single authorship was the norm in cited resources. Coupled with in-library use data, findings of the present study can be used to identify the core journal titles in librarianship as well as to evaluate the existing library collections to decide which journal titles to keep, discard, or relegate to off-site storage areas.  相似文献   

9.
The definition of the g-index is as arbitrary as that of the h-index, because the threshold number g2 of citations to the g most cited papers can be modified by a prefactor at one's discretion, thus taking into account more or less of the highly cited publications within a dataset. In a case study I investigate the citation records of 26 physicists and show that the prefactor influences the ranking in terms of the generalized g-index less than for the generalized h-index. I propose specifically a prefactor of 2 for the g-index, because then the resulting values are of the same order of magnitude as for the common h-index. In this way one can avoid the disadvantage of the original g-index, namely that the values are usually substantially larger than for the h-index and thus the precision problem is substantially larger; while the advantages of the g-index over the h-index are kept. Like for the generalized h-index, also for the generalized g-index different prefactors might be more useful for investigations which concentrate only on top scientists with high citation frequencies or on junior researchers with small numbers of citations.  相似文献   

10.
This paper introduces a new impact indicator for the research effort of a university, nh3. The number of documents or the number of citations obtained by an institution are used frequently in international ranking of institutions. However, these are very dependent on the size and this is inducing mergers with the apparent sole goal of improving the research ranking. The alternative is to use the ratio of the two measures, the mean citation rate, that is size independent but it has been shown to fluctuate along the time as a consequence of its dependence on a very small number of documents with an extremely good citation performance. In the last few years, the popularity of the Hirsch index as an indicator of the research performance of individual researchers led to its application to journals and institutions. However, the original aim of this h index of giving a mixed measure of the number of documents published and their impact as measured by the citations collected along the time is totally undesirable for institutions as the overall size may be considered irrelevant for the impact evaluation of research. Furthermore, the h index when applied to institutions tends to retain a very small number of documents making all other research production irrelevant for this indicator. The nh3 index proposed here is designed to measure solely the impact of research in a way that is independent of the size of the institution and is made relatively stable by making a 20-year estimate of the citations of the documents produced in a single year.  相似文献   

11.
在网页排名和论文排名基础上,采用引用频次标准和引文网络计算排名数值,建立专利排名算法。分析美国专利和商标局的数据库中的数字图书馆相关专利,研究结果显示专利排名算法能够区分相同引用次数的专利排名。该研究是网页排名算法的一种新型应用。  相似文献   

12.
Research on publication and citation patterns generally focuses on prolific or highly cited authors or on highly ranked programs. This study investigates the work and influence of a cross-section of library and information science (LIS) researchers at various stages of their academic lives, using a random sample of faculty members at programs accredited by the American Library Association. The analysis shows that the number of publications increases steadily as faculty rank advances. Assistant professors publish more conference papers and fewer journal articles, a pattern that is reversed with associate and full professors. Researchers used Web of Science® and Google™ Scholar to determine the influence of the publications. Web of Science reported no citations for most LIS faculty publications. With its broader scope, Google Scholar located more citations and revealed that the works of professors are cited significantly more frequently than publications by assistant or associate professors. When faculty profiles are compared by type of program, faculty members at schools granting doctoral degrees publish significantly more than their counterparts at schools where there is no doctoral program or where the doctoral degree is offered jointly with other academic units. When the comparison is made across ranks, full professors publish significantly more than faculty members at other ranks. There is no significant difference between assistant and associate professors.  相似文献   

13.
学术论著应杜绝无效引用   总被引：4，自引：1，他引：3  
陶范 《编辑学报》2007,19(3):173-175
学术论著中的一些过度标引、不相关引用、错误引用以及引用的信息滞后是一种无效引用,它影响论著的简洁表达,损害论证力度,浪费出版资源,影响引文计量的真实性.为杜绝无效引用,应破除对参考文献的认识误区,遵循必要性、准确性、新颖性的引用原则,重视作者的养成教育,帮助提高其论文写作水平,编辑则需严格核查把关.  相似文献   

14.
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15.
Objective:Systematic reviews and other evidence syntheses, the pinnacle of the evidence pyramid, embody comprehensiveness and rigor; however, retracted data are being incorporated into these publications. This study examines the use of retracted publications in the field of pharmacy, describes characteristics of retracted publications cited by systematic reviews, and discusses factors associated with citation likelihood.Methods:Using data from Retraction Watch, we identified retracted publications in the pharmacy field. We identified all articles citing these retracted publications in Web of Science and Scopus and limited results to systematic reviews. We classified the retraction reason, determined whether the citation occurred before or after retraction, and analyzed factors associated with the likelihood of systematic reviews citing a retracted publication.Results:Of 1,396 retracted publications, 283 were cited 1,096 times in systematic reviews. Most (65.0%) (712/1096) citations occurred before retraction. Citations were most often to items retracted due to data falsification or manipulation (39.2%), followed by items retracted due to ethical misconduct including plagiarism (30.4%), or concerns about or errors in data or methods (26.2%). Compared to those not cited in systematic reviews, cited items were significantly more likely to be retracted due to data falsification and manipulation, were published in high impact factor journals, and had longer delays between publication and retraction.Conclusions:Further analysis of systematic reviews citing retracted publications is needed to determine the impact of flawed data. Librarians understand the nuances involved and can advocate for greater transparency around the retraction process and increase awareness of challenges posed by retractions.  相似文献   

16.
Between 1965 and 1980, the Library Research and Demonstration Branch within the Department of Education awarded over $25 million to 312 projects. By tracing the citations in Social Sciences Citation Index from a random sampling of 52% of these projects, this study has attempted to assess the dissemination and impact of the projects in the professional literature.Approximately half of the projects were not cited in SSCI. The citations tended to be clustered among a small number of library-related serials. A small number of funded projects accounted for a large number of the citations. The most cited projects cost only one-fifth as much as the most expensive studies, yet were cited nearly five times as often.  相似文献   

17.
期刊h型指数与论文数量和被引的关系实证   总被引：3，自引：0，他引：3  
赵星  高小强 《图书情报工作》2009,53(20):131-134
以SSCI收录的国际图书情报学期刊10年论文及其被引记录为例,探讨期刊h型指数与反映论文数量和被引指标间的实证关系。结果表明：期刊h型指数主要受被引数量指标和被引广度指标所影响,且被引数量的影响略大于被引广度影响的两倍;期刊h型指数与期刊论文被引总数、篇均被引、引用该期刊的论文数、期刊影响因子显著正相关;各h型指数相互也强相关;样本期刊h型指数均没有表现出与论文数量的相关关系。  相似文献   

18.
The citation counts are increasingly used to assess the impact on the scientific community of publications produced by a researcher, an institution or a country. There are many institutions that use bibliometric indicators to steer research policy and for hiring or promotion decisions. Given the importance that counting citations has today, the aim of the work presented here is to show how citations are distributed within a scientific area and determine the dependence of the citation count on the article features. All articles referenced in the Web of Science in 2004 for Biology & Biochemistry, Chemistry, Mathematics and Physics were considered.We show that the distribution of citations is well represented by a double exponential-Poisson law. There is a dependence of the mean citation rate on the number of co-authors, the number of addresses and the number of references, although this dependence is a little far from the linear behaviour. For the relation between the mean impact and the number of pages the dependence obtained was very low. For Biology & Biochemistry and Chemistry we found a linear behaviour between the mean citation per article and impact factor and for Mathematics and Physics the results obtained are near to the linear behaviour.  相似文献   

19.
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   

20.
The purpose of this study was to identify objectively a hierarchical ranking of journals for health sciences librarians with faculty status. Such a guideline can indicate a journal's value for promotion and tenure consideration. Lists of recent research articles (1982-1986) in health sciences librarianship, and articles written by health sciences librarians, were compiled by searching Social SCISEARCH and MEDLINE. The journals publishing those articles are presented. Results show BMLA as the most prominent journal in the field. Therefore, citations from articles in BMLA from 1982 to 1986 were chosen as a sample for citation analysis. Citation analysis was employed to identify the most frequently cited journals. Some characteristics of the citations in BMLA are also discussed. The ranking of journals based on citation frequency, as a result, was identified.  相似文献   

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