Mapping the structure of science through usage

Summary Science has traditionally been mapped on the basis of authorship and citation data. Due to publication and citation delays such data represents the structure of science as it existed in the past. We propose to map science by proxy of journal relationships derived from usage data to determine research trends as they presently occur. This mapping is performed by applying a principal components analysis superimposed with a k-means cluster analysis on networks of journal relationships derived from a large set of article usage data collected for the Los Alamos National Laboratory research community. Results indicate that meaningful maps of the interests of a local scientific community can be derived from usage data. Subject groupings in the mappings corresponds to Thomson ISI subject categories. A comparison to maps resulting from the analysis of 2003 Thomson ISI Journal Citation Report data reveals interesting differences between the features of local usage and global citation data.     

Reconsidering the gold open access citation advantage postulate in a multidisciplinary context: an analysis of the subject categories in the Web of Science database 2009–2014

Since Lawrence in 2001 proposed the open access (OA) citation advantage, the potential benefit of OA in relation to citation impact has been discussed in depth. The methodology to test this postulate ranges from comparing the impact factors of OA journals versus traditional ones, to comparing citations of OA versus non-OA articles published in the same non-OA journals. However, conclusions are not entirely consistent among fields, and two possible explications have been suggested in those fields where a citation advantage has been observed for OA: the early view and the selection bias postulates. In this study, a longitudinal and multidisciplinary analysis of gold OA citation advantage is developed. All research articles in all journals for all subject categories in the multidisciplinary database Web of Science are considered. A total of 1,138,392 articles—60,566 (5.3%) OA articles and 1,077,826 (94.7%) non-OA articles—published in 2009 are analysed. The citation window considered goes from 2009 to 2014, and data are aggregated for the 249 disciplines (subject categories). At journal level, we also study the evolution of journal impact factors for OA and non-OA journals in those disciplines whose OA prevalence is higher (top 36 subject categories). As the main conclusion, there is no generalizable gold OA citation advantage, neither at article nor at journal level.     

Global knowledge management research: A bibliometric analysis

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.     

Interdisciplinarity and insularity in the diffusion of knowledge: an analysis of disciplinary boundaries between philosophy of science and the sciences

Two fundamentally different perspectives on knowledge diffusion dominate debates about academic disciplines. On the one hand, critics of disciplinary research and education have argued that disciplines are isolated silos, within which specialists pursue inward-looking and increasingly narrow research agendas. On the other hand, critics of the silo argument have demonstrated that researchers constantly import and export ideas across disciplinary boundaries. These perspectives have different implications for how knowledge diffuses, how intellectuals gain and lose status within their disciplines, and how intellectual reputations evolve within and across disciplines. We argue that highly general claims about the nature of disciplinary boundaries are counterproductive, and that research on the nature of specific disciplinary boundaries is more useful. To that end, this paper uses a novel publication and citation network dataset and statistical models of citation networks to test hypotheses about the boundaries between philosophy of science and 11 disciplinary clusters. Specifically, we test hypotheses about whether engaging with and being cited by scientific communities outside philosophy of science has an impact on one’s position within philosophy of science. Our results suggest that philosophers of science produce interdisciplinary scholarship, but they tend not to cite work by other philosophers when it is published in journals outside of their discipline. Furthermore, net of other factors, receiving citations from other disciplines has no meaningful impact—positive or negative—on citations within philosophy of science. We conclude by considering this evidence for simultaneous interdisciplinarity and insularity in terms of scientific trading theory and other work on disciplinary boundaries and communication.     

Hypothetical influence of non-indexed Spanish medical journals on the impact factor of the Journal Citation Reports-indexed journals

The purpose of this study is to analyze the hypothetical changes in the 2002 impact factor (IF) of the biomedical journals included in the Science Citation Index-Journal Citation Reports (SCI-JCR) by also taking into account cites coming from 83 non-indexed Spanish journals on different medical specialties. A further goal of the study is to identify the subject categories of the SCI-JCR with the largest increase in their IF, and to estimate the 2002 hypothetical impact factor (2002 HIF) of these 83 non-indexed Spanish journals. It is demonstrated that the inclusion of cites from a selection of non SCI-JCR-indexed Spanish medical journals in the SCI-JCR-indexed journals produces a slight increase in their 2002 IF, specially in journals edited in the USA and in the UK. More than half of the non-indexed Spanish journals has a higher 2002 HIF than that of the SCI-JCR-indexed journal with the lowest IF in the same subject category.     

Extending citer analysis to journal impact evaluation

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.     

Citedness and uncitedness of cancer articles

There is a rapid growth of cancer literature. Thousands of papers are being regularly published every year not only in speciality journals, but also in journals of other disciplines. Citation studies are nowadays considered a major basis of science indicators for ascertaining the importance of a scientific journal and that of the published articles on a particular subject. In oncological research the journalCancer is considered as one of the top most journals and is universally well known for its high standard and excellence. In this paper an attempt has been made to find out the importance of all the articles published in it for a particular year. Side by side bibliometric analysis was made to ascertain various other aspects like time lag between publication and first citation of articles, average citation time, subject scattering and identification of most important journals in the field etc. It is believed that this study would be of help to the working oncologists, librarians and information scientists to assess the importance of articles published in a top ranking journal of cancer and also that of different journals publishing oncological research results.     

The relationship between international editorial board composition and citation measures in political science,business, and genetics journals

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.     

Positive and negative aspects of citation indices and journal impact factors

The Hirsch citation index h is nowadays the most frequently used numerical indicator for the performance of scientists as reflected in their output and in the reaction of the scientific community reflected in citations of individual contributions. A few of the possible improvements of h are briefly reviewed. Garfield??s journal impact factor (IF) characterizes the reaction of the scientific community to publications in journals, reflected in citations of all papers published in any given journal during the preceding 2?years, and normalized against all citable articles during the same period. Again, a few of the possible improvements or supplements of IF are briefly reviewed, including the journal-h index proposed by Braun, Gl?nzel, and Schubert. Ascribing higher weighting factors to citations of individual papers proportionally to IF is considered to be a misuse of useful numerical indices based on citations. At most, one could turn this argument on its head and one can find reasons to ascribe an inverse proportionality relative to IF for individual citations: if a paper is considered worthy to be cited even if it was published in a low-IF journal, that citation ought to be worth more than if the citation would have been from a higher-impact journal. A weight factor reflecting the prestige of the citing author(s) may also be considered.     

The influence of the publication delay on journal rankings according to the impact factor

Summary  The inter-citation journal group is defined as a group of journals with inter-citation relations. In this paper, according to the 2003 JCR, an inter-citation relation matrix of 10 medical journals is established. Based on the transfer function model of the disturbed citing process, the calculation formula of journal impact factor disturbed by publication delays of certain journal in the group is deduced and a changing process of every journal's impact factor caused by the increase of each journal's average publication delay is simulated. In the inter-citation journal group, when a journal's publication delay increase, impact factors of all journals will be decreased and rankings of journals according to the impact factor may be changed. The closer a citation relation between two journals, the stronger the interaction of them and the larger the decrease of their impact factors caused by the increase of their publication delays.     

A bibliometric analysis and comparison on three information science journals: JASIST,IPM, JOD, 1998–2008

Employing a citation analysis, this study explored and compared the bibliometric characteristics and the subject relationship with other disciplines of and among the three leading information science journals, Journal of the American Society for Information Science and Technology (JASIST), Information Processing and Management and Journal of Documentation. The citation data were drawn from references of each article of the three journals during 1998 and 2008. The Ulrich’s Periodical Directory, Library of Congress Subject Heading, retrieved from the WorldCat, and LISA database were used to identify the main class, subclass and subject of cited journals and books. Quantitative results on the number of JASIST, IPM and JOD literature references, average number of references cited per paper, document type of cited literature and the journal self-citation rate are reported. Moreover, the highly cited journals and books, the main classes and subclasses of cited journals and books in papers of the three journals, the highly cited subjects in journals and books of library and information science were identified and analyzed. Comparison on the characteristics of cited journals and books confirmed that all the three journals under study are information science oriented, except JOD which is library science orientation. JASIST and IPM are very much in common and diffuse to other disciplines more deeply than JOD.     

Citation analysis and peer ranking of Australian social science journals

Citation analyses were performed for Australian social science journals to determine the differences between data drawn from Web of Science and Scopus. These data were compared with the tier rankings assigned by disciplinary groups to the journals for the purposes of a new research assessment model, Excellence in Research for Australia (ERA), due to be implemented in 2010. In addition, citation-based indicators including an extended journal impact factor, the h-index, and a modified journal diffusion factor, were calculated to assess whether subsequent analyses influence the ranking of journals. The findings suggest that the Scopus database provides higher number of citations for more of the journals. However, there appears to be very little association between the assigned tier ranking of journals and their rank derived from citations data. The implications for Australian social science researchers are discussed in relation to the use of citation analysis in the ERA.     

Citation regression analysis of computer science publications in different ranking categories and subfields

A number of bibliometric studies point out that the role of conference publications in computer science differs from that in other traditional fields. Thus, it is interesting to identify the relative status of journal and conference publications in different subfields of computer science based on the citation rates categorised by the China Computer Federation (CCF) classifications and venue types. In this research, we construct a dataset containing over 100,000 papers recommended by the CCF catalogue and their citation information. We also investigate some other factors that often influence a paper’s citation rate. An experimental study shows that the relative status of journals and conferences varies greatly in different subfields of computer science, and the impact of different publication levels varies according to the citation rate. We also verify that the classification of a publication, number of authors, maximum h-index of all authors of a paper, and average number of papers published by a publication have different effects on the citation rate, although the citation rate may have a different degree of correlation with these factors.     

Investigating disciplinary differences in the relationships between citations and downloads

Several studies have examined the relationships between citation and download data. Some have also analyzed disciplinary differences in the relationships by comparing a few subject areas or a few journals. To gain a deeper understanding of the disciplinary differences, we carried out a comprehensive study investigating the issue in five disciplines of science, engineering, medicine, social sciences, and humanities. We used a systematic method to select fields and journals ensuring a very broad spectrum and balanced representation of various academic fields. A total of 69 fields and 150 journals were included. We collected citation and download data for these journals from China Academic Journal Network Publishing Database, the largest Chinese academic journal database in the world. We manually filtered out non-research papers such as book reviews and editorials. We analyzed the relationships both at the journal and the paper level. The study found that social sciences and humanities are different from science, engineering, and medicine and that the pattern of differences are consistent across all measures studied. Social sciences and humanities have higher correlations between citations and downloads, higher correlations between downloads per paper and Journal Impact Factor, and higher download-to-citation ratios. The disciplinary differences mean that the accuracy or utility of download data in measuring the impact are higher in social sciences and humanities and that download data in those disciplines reflect or measure a broader impact, much more than the impact in citing authors.     

Analysis of publication patterns in Korean library and information science research

This study assessed research patterns and trends of library and information science (LIS) in Korea by applying bibliometric analysis to 159 Korean LIS professors?? 2,401 peer-reviewed publications published between 2001 and 2010. Bibliometric analysis of publication data found an increasing trend for collaboration, robust publication patterns, increasing number of international publications, and internationalization of LIS in Korea. The maturation and internalization of LIS research was evidenced in increased number of publications in high impact journals (e.g., SSI, SSCI), growing participation in leading international conferences (e.g., ASIST, TREC), increasing proportion of Korean LIS faculty with international degrees, and high publication rates by professors with international degrees. Though limited in its evaluative power without citation data, publication data can be a rich source for bibliometric analysis as this study has shown. The analysis of publication patterns conducted by the study, which is a first step in our aim to establish a multi-faceted approach for assessing the impact of scholarly work, will be followed up in a future study, where the question of quantity versus quality will be examined by comparing publication counts with citation counts.     

Quantitative study on Australian academic science

As at the end of 2009, 50 million scholarly papers were in existence, and changes in the global higher education sector are seeing this number grow rapidly. With the impact of university ranking schemes, dramatic changes have occurred in the academic publication system; both the number of publications, and the number of scholars, are increasing rapidly. In this research, we conduct a focused study on the quantitative relationships in Australian academic science. Sample data is selected from three institutions, representing three types of universities in Australia: a leading university, a middle-tier university, and a non-comprehensive university. For our analysis, bibliometric data for 32,056 scholars and 353,334 publications are downloaded. The results show that varying growth rates for scholars (5.6, 6.1, and 7.7%) and journal publications (6.7, 7.4, and 9.7%) for the leading university, the middle-tier university, and the non-comprehensive university respectively. We also evaluate how scholarly publications differ across these three Australian universities types from six aspects: average number of publications per scholar, percentage of first-authored publications, collaboration pattern, average SJR score of publishing journals, percentage of Quartile category of publishing journals, and average citation per publication. Lastly, we consider how the scholarship life-cycle varies in Australian universities in terms of publishing age, thus establishing the quantitative relationship between scholarship life-cycle and publishing performance in Australian universities.     

Article-count impact factor of materials science journals in SCI database

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.     

Publication delays in the science field and their relationship to the ageing of scientific literature

This article presents an exploratory analysis of publication delays in the science field. Publication delay is defined as the time period between submission and publication of an article for a scientific journal. We obtained a first indication that these delays are longer with regard to journals in the fields of mathematics and technical sciences than they are in other fields of science. We suggest the use of data on publication delays in the analysis of the effects of electronic publishing on reference/citation patterns. A preliminary analysis on a small sample suggests that—under rather strict assumptions—the cited half-life of references may be reduced with a factor of about 2 if publication delays decrease radically.     

Relativity of citation performance and excellence measures: From cross-field to cross-scale effects of field-normalisation

Summary As citation practices strongly depend on fields, field normalisation is recognised as necessary for fair comparison of figures in bibliometrics and evaluation studies. However fields may be defined at various levels, from small research areas to broad academic disciplines, and thus normalisation values are expected to vary. The aim of this project was to test the stability of citation ratings of articles as the level of observation - hence the basis of normalisation - changes. A conventional classification of science based on ISI subject categories and their aggregates at various scales was used, namely at five levels: all science, large academic discipline, sub-discipline, speciality and journal. Among various normalisation methods, we selected a simple ranking method (quantiles), based on the citation score of the article in each particular aggregate (journal, speciality, etc.) it belonged to at each level. The study was conducted on articles in the full SCI range, for publication year 1998 with a four-year citation window. Stability is measured in three ways: overall comparison of article rankings; individual trajectory of articles; survival of the top-cited class across levels. Overall rank correlations on the observed empirical structure are benchmarked against two fictitious sets that keep the same embedded structure of articles but reassign citation scores either in a totally ordered or in a totally random distribution. These sets act respectively as a 'worst case' and 'best case' for the stability of citation ratings. The results show that: (a) the average citation rankings of articles substantially change with the level of observation (b) observation at the journal level is very particular, and the results differ greatly in all test circumstances from all the other levels of observation (c) the lack of cross-scale stability is confirmed when looking at the distribution of individual trajectories of articles across the levels; (d) when considering the top-cited fractions, a standard measure of excellence, it is found that the contents of the 'top-cited' set is completely dependent on the level of observation. The instability of impact measures should not be interpreted in terms of lack of robustness but rather as the co-existence of various perspectives each having their own form of legitimacy. A follow-up study will focus on the micro levels of observation and will be based on a structure built around bibliometric groupings rather than conventional groupings based on ISI subject categories.     

The journal relative impact: an indicator for journal assessment

This paper presents the journal relative impact (JRI), an indicator for scientific evaluation of journals. The JRI considers in its calculation the different culture of citations presented by the Web of Science subject categories. The JRI is calculated considering a variable citation window. This citation window is defined taking into account the time required by each subject category for the maturation of citations. The type of document considered in each subject category depends on its outputs in relation to the citations. The scientific performance of each journal in relation to each subject category that it belongs to is considered allowing the comparison of the scientific performance of journals from different fields. The results obtained show that the JRI can be used for the assessment of the scientific performance of a given journal and that the SJR and SNIP should be used to complement the information provided by the JRI. The JRI presents good features as stability over time and predictability.