-
Garfield, E.: Recollections of Irving H. Sher 1924-1996 : Polymath/information scientist extraordinaire (2001)
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- Abstract
- Over a 35-year period, Irving H. Sher played a critical role in the development and implementation of the Science Citation Index and other ISI products. Trained as a biochemist, statistician, and linguist, Sher brought a unique combination of talents to ISI as Director of Quality Control and Director of Research and Development. His talents as a teacher and mentor evoked loyalty. He was a particularly inventive but self-taught programmer. In addition to the SCI, Social Sciences Citation Index, and Arts and Humanities Citation Index,
- Date
- 16.12.2001 14:01:22
- Object
- Science Citation Index
Social Sciences Citation Index
Arts and Humanities Citation Index
-
Malanga, G.: Classifying and screening journal literature with citation data (1982)
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- Object
- Science citation index
Social sciences citation index
- Source
- Universal classification I: subject analysis and ordering systems. Proc. of the 4th Int. Study Conf. on Classification Research, Augsburg, 28.6.-2.7.1982. Ed.: I. Dahlberg
-
H-Index auch im Web of Science (2008)
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- Content
- "Zur Kurzmitteilung "Latest enhancements in Scopus: ... h-Index incorporated in Scopus" in den letzten Online-Mitteilungen (Online-Mitteilungen 92, S.31) ist zu korrigieren, dass der h-Index sehr wohl bereits im Web of Science enthalten ist. Allerdings findet man/frau diese Information nicht in der "cited ref search", sondern neben der Trefferliste einer Quick Search, General Search oder einer Suche über den Author Finder in der rechten Navigationsleiste unter dem Titel "Citation Report". Der "Citation Report" bietet für die in der jeweiligen Trefferliste angezeigten Arbeiten: - Die Gesamtzahl der Zitierungen aller Arbeiten in der Trefferliste - Die mittlere Zitationshäufigkeit dieser Arbeiten - Die Anzahl der Zitierungen der einzelnen Arbeiten, aufgeschlüsselt nach Publikationsjahr der zitierenden Arbeiten - Die mittlere Zitationshäufigkeit dieser Arbeiten pro Jahr - Den h-Index (ein h-Index von x sagt aus, dass x Arbeiten der Trefferliste mehr als x-mal zitiert wurden; er ist gegenüber sehr hohen Zitierungen einzelner Arbeiten unempfindlicher als die mittlere Zitationshäufigkeit)."
- Date
- 6. 4.2008 19:04:22
- Object
- H-Index
-
Rajan, T.N.; Guha, B.; Sayanarayana, R.: Associate relationship of concepts as seen through citations and citation index (1982)
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- Source
- Universal classification II: subject analysis and ordering systems. Proc. of the 4th Int. Study Conf. on Classification research, Augsburg, 28.6.-2.7.1982. Ed.: I. Dahlberg
-
Gorraiz, J.; Purnell, P.J.; Glänzel, W.: Opportunities for and limitations of the Book Citation Index (2013)
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- Abstract
- This article offers important background information about a new product, the Book Citation Index (BKCI), launched in 2011 by Thomson Reuters. Information is illustrated by some new facts concerning The BKCI's use in bibliometrics, coverage analysis, and a series of idiosyncrasies worthy of further discussion. The BKCI was launched primarily to assist researchers identify useful and relevant research that was previously invisible to them, owing to the lack of significant book content in citation indexes such as the Web of Science. So far, the content of 33,000 books has been added to the desktops of the global research community, the majority in the arts, humanities, and social sciences fields. Initial analyses of the data from The BKCI have indicated that The BKCI, in its current version, should not be used for bibliometric or evaluative purposes. The most significant limitations to this potential application are the high share of publications without address information, the inflation of publication counts, the lack of cumulative citation counts from different hierarchical levels, and inconsistency in citation counts between the cited reference search and the book citation index. However, The BKCI is a first step toward creating a reliable and necessary citation data source for monographs - a very challenging issue, because, unlike journals and conference proceedings, books have specific requirements, and several problems emerge not only in the context of subject classification, but also in their role as cited publications and in citing publications.
- Object
- Book Citation Index
-
Malin, M.V.: ¬The Science Citation Index : a new concept in indexing (1968)
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- Object
- Science Citation Index
-
Safder, I.; Ali, M.; Aljohani, N.R.; Nawaz, R.; Hassan, S.-U.: Neural machine translation for in-text citation classification (2023)
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- Abstract
- The quality of scientific publications can be measured by quantitative indices such as the h-index, Source Normalized Impact per Paper, or g-index. However, these measures lack to explain the function or reasons for citations and the context of citations from citing publication to cited publication. We argue that citation context may be considered while calculating the impact of research work. However, mining citation context from unstructured full-text publications is a challenging task. In this paper, we compiled a data set comprising 9,518 citations context. We developed a deep learning-based architecture for citation context classification. Unlike feature-based state-of-the-art models, our proposed focal-loss and class-weight-aware BiLSTM model with pretrained GloVe embedding vectors use citation context as input to outperform them in multiclass citation context classification tasks. Our model improves on the baseline state-of-the-art by achieving an F1 score of 0.80 with an accuracy of 0.81 for citation context classification. Moreover, we delve into the effects of using different word embeddings on the performance of the classification model and draw a comparison between fastText, GloVe, and spaCy pretrained word embeddings.
-
ISI offers intranet access to its citation index databases (1997)
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- Abstract
- Announces the availability of the Web of Science, a proprietary Web browser providing intranet access to the Citation Index databases from ISI. The new browser interface will allow researcher to browse indexed information and perform further research. Describes search options
- Object
- Science citation index
Social sciences citation index
-
Tay, A.: ¬The next generation discovery citation indexes : a review of the landscape in 2020 (2020)
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- Abstract
- Conclusion There is a reason why Google Scholar and Web of Science/Scopus are kings of the hills in their various arenas. They have strong brand recogniton, a head start in development and a mass of eyeballs and users that leads to an almost virtious cycle of improvement. Competing against such well established competitors is not easy even when one has deep pockets (Microsoft) or a killer idea (scite). It will be interesting to see how the landscape will look like in 2030. Stay tuned for part II where I review each particular index.
- Date
- 17.11.2020 12:22:59
-
Larivière, V.; Gingras, Y.; Archambault, E.: ¬The decline in the concentration of citations, 1900-2007 (2009)
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- Abstract
- This article challenges recent research (Evans, 2008) reporting that the concentration of cited scientific literature increases with the online availability of articles and journals. Using Thomson Reuters' Web of Science, the present article analyses changes in the concentration of citations received (2- and 5-year citation windows) by papers published between 1900 and 2005. Three measures of concentration are used: the percentage of papers that received at least one citation (cited papers); the percentage of papers needed to account for 20%, 50%, and 80% of the citations; and the Herfindahl-Hirschman index (HHI). These measures are used for four broad disciplines: natural sciences and engineering, medical fields, social sciences, and the humanities. All these measures converge and show that, contrary to what was reported by Evans, the dispersion of citations is actually increasing.
- Date
- 22. 3.2009 19:22:35
-
Small, H.; Sweeney, E.: Clustering the Science Citation Index using co-citations (1985)
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-
Vanclay, J.K.: On the robustness of the h-index (2007)
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- Abstract
- The h-index (Hirsch, 2005) is robust, remaining relatively unaffected by errors in the long tails of the citations-rank distribution, such as typographic errors that short-change frequently cited articles and create bogus additional records. This robustness, and the ease with which h-indices can be verified, support the use of a Hirsch-type index over alternatives such as the journal impact factor. These merits of the h-index apply both to individuals and to journals.
-
Leydesdorff, L.: Can scientific journals be classified in terms of aggregated journal-journal citation relations using the Journal Citation Reports? (2006)
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- Abstract
- The aggregated citation relations among journals included in the Science Citation Index provide us with a huge matrix, which can be analyzed in various ways. By using principal component analysis or factor analysis, the factor scores can be employed as indicators of the position of the cited journals in the citing dimensions of the database. Unrotated factor scores are exact, and the extraction of principal components can be made stepwise because the principal components are independent. Rotation may be needed for the designation, but in the rotated solution a model is assumed. This assumption can be legitimated on pragmatic or theoretical grounds. Because the resulting outcomes remain sensitive to the assumptions in the model, an unambiguous classification is no longer possible in this case. However, the factor-analytic solutions allow us to test classifications against the structures contained in the database; in this article the process will be demonstrated for the delineation of a set of biochemistry journals.
-
Moed, H.F.; Leeuwen, T.N. van; Reedijk, J.: ¬A new classification system to describe the ageing of scientific journals and their impact factors (1998)
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- Abstract
- During the past decades, journal impact data obtained from the Journal Citation Reports (JCR) have gained relevance in library management, research management and research evaluation. Hence, both information scientists and bibliometricians share the responsibility towards the users of the JCR to analyse the reliability and validity of its measures thoroughly, to indicate pitfalls and to suggest possible improvements. In this article, ageing patterns are examined in 'formal' use or impact of all scientific journals processed for the Science Citation Index (SCI) during 1981-1995. A new classification system of journals in terms of their ageing characteristics is introduced. This system has been applied to as many as 3,098 journals covered by the Science Citation Index. Following an earlier suggestion by Glnzel and Schoepflin, a maturing and a decline phase are distinguished. From an analysis across all subfields it has been concluded that ageing characteristics are primarily specific to the individual journal rather than to the subfield, while the distribution of journals in terms of slowly or rapidly maturing or declining types is specific to the subfield. It is shown that the cited half life (CHL), printed in the JCR, is an inappropriate measure of decline of journal impact. Following earlier work by Line and others, a more adequate parameter of decline is calculated taking into account the size of annual volumes during a range of fifteen years. For 76 per cent of SCI journals the relative difference between this new parameter and the ISI CHL exceeds 5 per cent. The current JCR journal impact factor is proven to be biased towards journals revealing a rapid maturing and decline in impact. Therefore, a longer term impact factor is proposed, as well as a normalised impact statistic, taking into account citation characteristics of the research subfield covered by a journal and the type of documents published in it. When these new measures are combined with the proposed ageing classification system, they provide a significantly improved picture of a journal's impact to that obtained from the JCR.
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Leydesdorff, L.: On the normalization and visualization of author co-citation data : Salton's Cosine versus the Jaccard index (2008)
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- Abstract
- The debate about which similarity measure one should use for the normalization in the case of Author Co-citation Analysis (ACA) is further complicated when one distinguishes between the symmetrical co-citation - or, more generally, co-occurrence - matrix and the underlying asymmetrical citation - occurrence - matrix. In the Web environment, the approach of retrieving original citation data is often not feasible. In that case, one should use the Jaccard index, but preferentially after adding the number of total citations (i.e., occurrences) on the main diagonal. Unlike Salton's cosine and the Pearson correlation, the Jaccard index abstracts from the shape of the distributions and focuses only on the intersection and the sum of the two sets. Since the correlations in the co-occurrence matrix may be spurious, this property of the Jaccard index can be considered as an advantage in this case.
- Object
- Salton's Cosine index
Jaccard index
-
McVeigh, M.E.: Citation indexes and the Web of Science (2009)
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- Abstract
- The Web of Science, an online database of bibliographic information produced by Thomson Reuters- draws its real value from the scholarly citation index at its core. By indexing the cited references from each paper as a separate part of the bibliographic data, a citation index creates a pathway by which a paper can be linked backward in time to the body of work that preceded it, as well as linked forward in time to its scholarly descendants. This entry provides a brief history of the development of the citation index, its core functionalities, and the way these unique data are provided to users through the Web of Science.
- Object
- Science Citation Index
Social Sciences Citation Index
Arts and Humanities Citation Index
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Göbel, S.: What the Citation Index is good for (1997)
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- Footnote
- Ein Leserbrief zu Sinn und Nutzen des Science Citation Index als Erwiderung auf einen Beitrag von A. Octavio in Mathematical intelligencer 18(1996) no.4, S.9-11
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Glänzel, W.: Visual bibliometrics : eine visuelle Oberfläche zur Erweiterung der Nutzungsmöglichkeiten bibliographischer Datenbanken (1996)
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- Abstract
- In einer früheren Studie wurde bereits der 'informationelle Mehrwert' von bibliographischen Datenbanken durch bibliometrische Nutzung untersucht. Im folgenden soll nun eine visuelle Oberfläche vorgestellt werden, die mit Hilfe einer bibliometrischen 'Sekundärdatenbank' einerseits die Nutzungsmöglichkeiten der zugrundeliegenden bibliographischen Datenbanken vor allem in den Bereichen Wissenschaftsinformation, Forschungsevaluation und Wissenschaftspolitik erweitern soll, andererseits aber auch eine Rückkopplung zu den Aufgaben des traditionellen Retrievals erlaubt. Die visuelle Oberfläche 'Visual Bibliometrics' ist eine Erweiterung des CD-Edition des 'Science Citation Index' und des 'Social Science Citation Index'
- Object
- Science Citation Index
Social Sciences Citation Index
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Tsay, M.-Y.: From Science Citation Index to Journal Citation Reports, amd criteria for journals evaluation (1997)
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- Abstract
- Investigates the characteristics of Journal Citation Reports (JCR) through the study of the Science Citation Index (SCI). Other criteria for evaluating a journal are also discussed. The compilation process of SCI data, and the characteristics, applications and limitations of SCI are studied. A detailed description of JCR is provided including: journal ranking listing, citing journal listing, cited journal listing, subject category listing, source data, impact factor, immediacy index, cited half-life and citing half-life. The applications and limitations of JCR are also explored. In addition to the criteria listed in JCR, the size, circulation and influence of journals are also considered significant criteria fir evaluation purposes
- Object
- Science Citation Index
-
Remler, A.: Lässt sich wissenschaftliche Leistung messen? : Wer zitiert wird, liegt vorne - in den USA berechnet man Forschungsleistung nach einem Zitat-Index (2000)
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