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1.
Summary The purpose of this study is to analyze and compare journal citation data, from Journal Citation Reports on the Web 2000, of general and internal medicine and surgery. The source items and five kinds of citation data, i.e. citation counts, impact factor, immediacy index, citing half-life and cited half-life are examined and the correlation between each of the fifteen pairs of citation data is determined based on the Pearson correlation tests. The Fishers Z-transform was employed to test the significant difference between the Pearson correlation coefficient for each pair of citation data of these two subject areas. The following results of this work reveal: the frequently published journals are cited more frequently and also with high impact factor and immediacy index, in addition, they are usually accompanied with short citing half-life (i.e., usually cite current literature). The impact factor and immediacy index has significant correlation with citation counts. A significant correlation also exists between impact factor and immediacy index. However there is no correlation between cited half-life and other citation data, except citing half-life. For journals of general and internal medicine and surgical medicine, there are no significant difference of the Pearson correlation coefficient for the following pair of citation data: source items and citation counts, source items and impact factor, source items and citing half-life, citation counts and citing half-life, impact factor and citing half-life, immediacy index and citing half-life, and cited half-life and citing half-life.  相似文献   

2.
This article introduces a new modified method for calculating the impact factor of journals based on the current ISI practice in generating journal impact factor values. The impact factor value for a journal calculated by the proposed method, the so-called Cited Half-Life Impact Factor (CHAL) method, which is based on the ratio of the number of current year citations of articles from the previous X years to that of articles published in the previous X years, the X value being equal to the value of the cited half-life of the journal in the current year. Thirty-four journals in the Polymer Science Category from the ISI Subject Heading Categories were selected and examined. Total citations, impact factors and cited half-life of the 34 journals during the last five years (1997-2001) were retrieved from the ISI Journal Citation Reports and were used as the data source for the calculations in this work, the impact factor values from ISI and CHAL methods then being compared. The positions of the journals ranked by impact factors obtained from the ISI method were different from those from the CHAL method. It was concluded that the CHAL method was more suitable for calculating the impact factor of the journals than the existing ISI method. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

3.
A citation report for Thai academic journals published during 1996-2000   总被引:1,自引:0,他引:1  
This article aimed to report Journal Impact Factor (J-IF) and Journal Immediacy Index (J-II) of 68 Thai academic journals during the past five years (from 1996 to 2000) using the calculation method given by the Institute for Scientific Information (ISI). This was the first time that the citation indexes of Thai academic journals were established. With respect to the journal impact factor, the results showed that only six journals have been cited continuously during the past five years, this being 8.8% of the total journal number selected in this work. It was also noticeable that articles published in longer journal age tended to have greater opportunity to be cited and higher journal impact factor. The average impact factor of the 68 journals was relatively low, this being of 0.069, suggesting that the possibility of an article published in a national journal to be cited was only 6.9%. In terms of the immediacy index, it was found that the average immediacy index value was 0.063, which was again very low. No significant relationship between the journal age and the immediacy index could be observed. 47% of the journals have never been able to produce the immediacy index in the past five years, suggesting that articles in the Thai academic journals were hardly cited within the same years they were published. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

4.
5.
Citations from 1980 to 1988, obtained from fifty biomedical journals covered by theJournal Citation Reports (JCR) are studied. In purely numerical terms, the evolution of each citation (journal citation), including its impact factor (IF), would depend essentially on three variables for each journal: (i) the yearly rate of increase of items that could be cited (citable items), (ii) the relative yearly increment of the citing journals, (iii) the relative yearly increment of citations. The mechanics of this give rise to the three standard patterns for journal citations, namely: (i) annual impact factors increase each year (ascending evolution), (ii) annual impact factors remain the same each year (constant evolution), (iii) annual impact factors decrease each year (descending evolution). The reason why some journal citation profiles do not fit into the standard patterns is presumably that forces are at work able to alter the numerical mechanics described. The concepts of saturation/unsaturation of the demand for scientific information are introduced, showing how they are reflected in the impact factor figures for the journals cited.  相似文献   

6.
By employing the Pearson correlation, Fisher-and t-tests, the present study analyzes and compares scientometric data including number of source items, number of citations, impact factor, immediacy index, citing half-life and cited half-life, for essential journals in physics, chemistry and engineering, from SCI JCR on the Web 2002. The results of the study reveal that for all the scientometric indicators, except the cited half-life, there is no significant mean difference between physics and chemistry subjects indicating similar citation behavior among the scientists. There is no significant mean difference in the citing half-life among the three subjects. Significant mean difference is generally observed for most of the scientometric indicators between engineering and physics (or chemistry) demonstrating the difference in citation behavior among engineering researchers and scientists in physics or chemistry. Significant correlations among number of source items, number of citations, impact factor, and immediacy index and between cited half-life and citing half-life generally prevail for each of the three subjects. On the contrary, in general, there is no significant correlation between the cited half-life and other scientometric indicators. The three subjects present the same strength of the correlations between number of source items and number of citations, between number of citations and impact factor, and between cited half-life and citing half-life.  相似文献   

7.
Simple quantitative indices of pair-wise journal citation relatedness (based on the numbers of references given to and received from a journal title, which are provided by Science Citation Index database) are translated by an automatic clustering procedure into a meaningful map diagram reflecting topical relatedness of journals within a field of science. Such a map for 60 journals in marine and freshwater biology and related sciences published in 1987 reveals a tight cluster of marine biology journals quite distinct from the freshwater biology journal cluster and from the fisheries cluster. The journals within the marine biology cluster and those with strongest pair-wise links with them can be regarded as the core journals in marine biology. Indices of unilateral citation relatedness are used to obtain diagrams, which we term citograms. The citograms visualize patterns of citation relatedness of a journal (its citing and being cited). Journal self-citation can be meaningfully estimated using the bilateral index of relatedness. Self-citation is high in specialized or regional journal titles. It also appears to be quite substantial in journals of broader scope, which possibly reflect authors' subjective preferences.  相似文献   

8.
Comparison of citation and usage indicators: the case of oncology journals   总被引:2,自引:0,他引:2  
It is the objective of this article to examine in which aspects journal usage data differ from citation data. This comparison is conducted both at journal level and on a paper by paper basis. At journal level, we define a so-called usage impact factor and a usage half-life in analogy to the corresponding Thomson’s citation indicators. The usage data were provided from Science Direct, subject category “oncology”. Citation indicators were obtained from JCR, article citations were retrieved from SCI and Scopus. Our study shows that downloads and citations have different obsolescence patterns. While the average cited half-life was 5.6 years, we computed a mean usage half-life of 1.7 years for the year 2006. We identified a strong correlation between the citation frequencies and the number of downloads for our journal sample. The relationship was lower when performing the analysis on a paper by paper basis because of existing variances in the citation-download-ratio among articles. Also the correlation between the usage impact factor and Thomson’s journal impact factor was “only” moderate because of different obsolescence patterns between downloads and citations.  相似文献   

9.
10.
Global knowledge management research: A bibliometric analysis   总被引:1,自引:0,他引:1  
Gu  Yinian 《Scientometrics》2004,61(2):171-190
The present study characterizes the dynamic publication activity of global knowledge management (KM) by data collected through a search restricted to articles in ISI Web of Science.A total of 2727 unique authors had contributed 1407 publications since 1975. The overwhelming majority (2349 or 86%) of them wrote one publication. The productive authors, their contribution and authorship position are listed to indicate their productivity and degree of involvement in their research publications. The sum of research output of the first or responsible authors from USA, UK and Germany reaches 57% of the total productivity. The distribution of articles is rather widespread - they published in 462 titles of serials, spanning 110 Journal Citation Reports subject categories. The higher quality journals make publication of findings more visible. A Pearson's correlation coefficient is statistically found to be significant between citation frequency of article and impact factor of journal, instead of authorship pattern. The results also indicate that R&D expenditures were actually not proportional to research productivity or citation counts. As the subject highly interacts with other disciplines, the field of KM has not yet developed its own body of literature. KM might have been evolving an interdisciplinary theory that is developing at the boundaries of scientific disciplines. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

11.
The paper examines the role played by the scientific journal in the citation process. It compares characteristics of journals which publish the articles cited and those which cite them. It pays attention to the regional location, degrees of specialization, and visibility of journals and investigates how these factors relate to accumulation of citations. The data consist of a subsample of Nordic cardiovascular research articles, published in 1981, and of the articles citing them until early 1988.  相似文献   

12.
Article-count impact factor of materials science journals in SCI database   总被引:2,自引:0,他引:2  
This article proposed a new index, so-called “Article-Count Impact Factor” (ACIF) for evaluating journal quality in light of citation behaviour in comparison with the ISI journal impact factors. The ACIF index was the ratio of the number of articles that were cited in the current year to the source items published in that journal during the previous two years. In this work, we used 171 journal titles in materials categories published in the years of 2001–2004 in international journals indexed in the Science Citation Index Expanded (SCI) database as data source. It was found that ACIF index could be used as an alternative tool in assessing the journal quality, particularly in the case where the assessed journals had the same (equal or similar) JIF values. The experimental results suggested that the higher the ACIF value, the more the number of articles being cited. The changes in ACIF values were more dependent on the JIF values rather than the total number of articles. Polymer Science had the greatest ACIF values, suggesting that the articles in Polymer Science had greater “citation per article” than those in Metallurgical Engineering and Ceramics. It was also suggested that in order to increase a JIF value of 1.000, Ceramics category required more articles to be cited as compared to Metallurgical Engineering and Polymer Science categories.  相似文献   

13.
The main purpose of this study was to analyze the Italian journals indexed in the 2000 edition of the Journal Citation Reports (JCR) published by the Institute for Scientific Information (ISI) (Philadelphia, USA). The performance and the visibility of these journals were evaluated in terms of Impact Factor (IF), mean IF from citing journals and cited journals, and self-citing and self-cited rates. Seventy-three Italian journals were indexed in the JCR, 14 of which achieved an IF equal to or higher than one. Most citing journals were European and American, thus showing a fairly good visibility of the articles published in the 14 journals analyzed. The self-citing and self-cited rates showed a wide variation. The journal that appeared to perform best was theJournal of High Energy Physics, an electronic publication whose success seemingly confirms Internet circulation as an effective means to enhance the visibility and consequently the quality, in term of citations, of a journal. Italy's low overall expenditure on research & development (R&D) and low number of researchers compared to countries with longstanding high publishing standards and traditions are no doubt partly to blame for its poor performance in scientific publishing. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

14.
All references data was extracted from the annual volumes of the CD-Edition of Science Citation Index (SCI) and the Web of Science of the Institute for Scientific Information (ISI), the journal citation and self-citation data extracted from the Journal Citation Report (JCR), the self-citing rate and self-cited rate calculated based on the JCR method. To determine the trend of mean value of references per paper throughout 1970–2005, a total number of 10,000 records were randomly chosen for each year of under study, and the mean value of references per paper was calculated. To determine the growth of journals IF a total number of 5,499 journals were chosen in the JCR in 2002 and the same set of journals in the year 2004. To show the trend of journals IF, all journals indexed in the JCR throughout 1999–2005 were extracted and the mean values of their IFs was calculated annually. The study showed that the number of references per paper from 1970 to 2005 has steady increased. It reached from 8.40 in 1970 to 34.63 in 2005, an increase of more than 4 times. The majority of publications (76.17%) were in the form of Journals Article. After articles, Meeting Abstracts (9.46%), Notes (3.90%) and Editorial Material (3.78%) are the most frequented publication forms, respectively. 94.57% of all publications were in English. After English, German (1.50%), Russian (1.48%) and French (1.37%) were the most frequented languages, respectively. The study furthermore showed that there is a significant correlation between the IF and total citation of journals in the JCR, and there is an important hidden correlation between IF and the self-citation of journals. This phenomena causes the elevation of journals IF. The more often a journal is citing other journals, the more often it is also cited (by a factor of 1.5) by others. In consequence the growing percentage of journal self-citation is followed by journal self-citedness, which can be considered as the Matthew Effect. There is a linear correlation between journal self-citing and journal self-cited value, the mean value of self-cited rate always stays higher than the self-citing rate. The mean value of self-cited rate in 2000 was 14% and the mean value of self-citing rate is 6.61%, whereas the mean value of self-cited rate in 2005 was 12% and the mean value of self-citing rate was 7.81%.  相似文献   

15.
Nisonger  Thomas E. 《Scientometrics》2002,54(2):257-268
Three measures of international composition on journal editorial boards - the number of countries represented on the board, the number of international members, and the proportion of international board members - were correlated with impact factor and total citation data in the 1999 Journal Citation Reportsfor 153 business, political science, and genetics journals. With a few exceptions the relationship between international editorial board composition and citation measures was non-linear, leading to the conclusion that international membership on the editorial board can not generally be used as a marker of better journal quality. Yet further investigation is warranted due to positive correlations between some editorial board and citation measures for non-U.S. business and political science journals. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

16.

This paper examines the citation impact of papers published in scientific-scholarly journals upon patentable technology, as reflected in examiner- or inventor-given references in granted patents. It analyses data created by SCImago Research Group, linking PATSTAT’s scientific non-patent references (SNPRs) to source documents indexed in Scopus. The frequency of patent citations to journal papers is calculated per discipline, year, institutional sector, journal subject category, and for “top” journals. PATSTAT/Scopus-based statistics are compared to those derived from Web of Science/USPTO linkage. A detailed assessment is presented of the technological impact of research publications in social sciences and humanities (SSH). Several subject fields perform well in terms of the number of citations from patents, especially Library and Information Science, Language and Linguistics, Education, and Law, but many of the most cited journals find themselves in the interface between SSH and biomedical or natural sciences. Analyses of the titles of citing patents and cited papers are presented that shed light upon the cognitive content of patent citations. It is proposed to develop more advanced indicators of citation impact of papers upon patents, and ways to combine citation counts with citation content and context analysis.

  相似文献   

17.
This study uses the method of citation context analysis to compare differences in citation contexts, including cited concepts and citation functions, between natural sciences (NS) and social sciences and humanities (SSH), based on articles citing Little Science, Big Science (LSBS) published between 1963 and 2010. The findings indicate that NS and SSH researchers frequently cite LSBS as a source that is related to a specific topic and as evidence to support a claim. No significant differences were identified in the distribution of cited concepts included in LSBS, but significant differences were observed in the reasons for citing LSBS between NS and SSH citing articles. However, reverse trends were observed in the percentage of some cited concepts and citation functions between NS and SSH, which implies that subtle differences in citation behavior exist between NS and SSH researchers. In addition, each concept category has a different half-life. Concepts related to characteristics of big science and scientific collaboration have the longest half-lives.  相似文献   

18.
The concept of citer analysis investigated earlier by Ajiferuke and Wolfram (In: B. Larsen, J. Leta (eds.) Proceedings of the 12th international conference of the international society for scientometrics and informetrics (ISSI) pp. 798–808, 2009, Scientometrics 83:623–638, 2010) is extended to journals where different citing units (citers, citing articles, citing journals) are compared with the journal impact factor and each other to determine if differences in ranking arise from different measures. The citer measures for the 31 high impact journals studied from information science and library science are significantly correlated, even more so than the earlier citer analysis findings, indicating that there is a close relationship among the different units of measure. Still, notable differences in rankings for the journals examined were evident for the different measures used, especially from either 5-year impact factor or number of citing articles per publication to the number of citing journals per publication. The journals that are adversely affected seem to be those whose citations are concentrated in a few journals. This informed the need to develop a journal citation concentration index, which can serve as a complementary measure to the existing journal impact indices.  相似文献   

19.
Naomi Fukuzawa 《Scientometrics》2017,112(2):1007-1023
This study explores how the citation of open access (OA) journal articles occurs by analyzing the impact of certain journal characteristics, namely, whether the journal is OA and whether its country of publication is the same as the affiliation of a paper’s author. As the language of a paper is an important factor contributing to paper citations, this study uses papers in English. This analysis included publications from 77 countries from 2010 to 2012. This analysis included 19,530 journals and 3,215,742 papers without duplication. The results showed that papers published in OA and international journals were cited in more countries than non-OA and domestic journals, and a higher percentage of these were being cited by foreign countries. From these findings, it was determined that the more widely accessible OA journals were effectively being accessed by researchers from multiple countries. However, of the top 10% most cited papers in international journals, a higher percentage of these came from non-OA compared to OA journals. Among domestic journals, no such difference was found. Papers published in non-OA international journals were most cited in foreign countries with a large number of published papers. Hence, the effect of OA’s expanded accessibility, while having an apparent effect on heightening the interest of foreign readership, has a limited impact in terms of increasing citations.  相似文献   

20.
Journal self-citation rates in ecological sciences   总被引:1,自引:0,他引:1  
Impact factors are a widely accepted means for the assessment of journal quality. However, journal editors have possibilities to influence the impact factor of their journals, for example, by requesting authors to cite additional papers published recently in that journal thus increasing the self-citation rate. I calculated self-citation rates of journals ranked in the Journal Citation Reports of ISI in the subject category “Ecology” (n = 107). On average, self citation was responsible for 16.2 ± 1.3% (mean ± SE) of the impact factor in 2004. The self-citation rates decrease with increasing journal impact, but even high impact journals show large variation. Six journals suspected to request for additional citations showed high self-citation rates, which increased over the last seven years. To avoid further deliberate increases in self-citation rates, I suggest to take journal-specific self-citation rates into account for journal rankings.  相似文献   

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