Literatur zur Informationserschließung
Diese Datenbank enthält über 40.000 Dokumente zu Themen aus den Bereichen Formalerschließung – Inhaltserschließung – Information Retrieval.
© 2015 W. Gödert, TH Köln, Institut für Informationswissenschaft
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1Franceschet, M.: ¬The large-scale structure of journal citation networks.
In: Journal of the American Society for Information Science and Technology. 63(2012) no.4, S.837-842.
Abstract: We analyze the large-scale structure of the journal citation network built from information contained in the Thomson-Reuters Journal Citation Reports. To this end, we explore network properties such as density, percolation robustness, average and largest node distances, reciprocity, incoming and outgoing degree distributions, and assortative mixing by node degrees. We discover that the journal citation network is a dense, robust, small, and reciprocal world. Furthermore, in- and outdegree node distributions display long tails, with few vital journals and many trivial ones, and they are strongly positively correlated.
Themenfeld: Informetrie
Objekt: Journal Citation Reports
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2Leydesdorff, L. ; Moya-Anegón, F.de ; Guerrero-Bote, V.P.: Journal maps on the basis of Scopus data : a comparison with the Journal Citation Reports of the ISI.
In: Journal of the American Society for Information Science and Technology. 61(2010) no.2, S.352-369.
Abstract: Using the Scopus dataset (1996-2007) a grand matrix of aggregated journal-journal citations was constructed. This matrix can be compared in terms of the network structures with the matrix contained in the Journal Citation Reports (JCR) of the Institute of Scientific Information (ISI). Because the Scopus database contains a larger number of journals and covers the humanities, one would expect richer maps. However, the matrix is in this case sparser than in the case of the ISI data. This is because of (a) the larger number of journals covered by Scopus and (b) the historical record of citations older than 10 years contained in the ISI database. When the data is highly structured, as in the case of large journals, the maps are comparable, although one may have to vary a threshold (because of the differences in densities). In the case of interdisciplinary journals and journals in the social sciences and humanities, the new database does not add a lot to what is possible with the ISI databases.
Themenfeld: Informetrie ; Citation indexing
Objekt: Scopus ; Journal Citation Reports
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3West, J. ; Bergstrom, T. ; Bergstrom, C.T.: Big Macs and Eigenfactor scores : don't let correlation coefficients fool you.
In: Journal of the American Society for Information Science and Technology. 61(2010) no.9, S.1800-1807.
Abstract: The Eigenfactor(TM) Metrics provide an alternative way of evaluating scholarly journals based on an iterative ranking procedure analogous to Google's PageRank algorithm. These metrics have recently been adopted by Thomson Reuters and are listed alongside the Impact Factor in the Journal Citation Reports. But do these metrics differ sufficiently so as to be a useful addition to the bibliometric toolbox? Davis (2008) has argued that they do not, based on his finding of a 0.95 correlation coefficient between Eigenfactor score and Total Citations for a sample of journals in the field of medicine. This conclusion is mistaken; in this article, we illustrate the basic statistical fallacy to which Davis succumbed. We provide a complete analysis of the 2006 Journal Citation Reports and demonstrate that there are statistically and economically significant differences between the information provided by the Eigenfactor Metrics and that provided by Impact Factor and Total Citations.
Themenfeld: Informetrie
Objekt: Journal Citation Reports
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4Leydesdorff, L. ; Rafols, I.: ¬A global map of science based on the ISI subject categories.
In: Journal of the American Society for Information Science and Technology. 60(2009) no.2, S.348-362.
Abstract: The decomposition of scientific literature into disciplinary and subdisciplinary structures is one of the core goals of scientometrics. How can we achieve a good decomposition? The ISI subject categories classify journals included in the Science Citation Index (SCI). The aggregated journal-journal citation matrix contained in the Journal Citation Reports can be aggregated on the basis of these categories. This leads to an asymmetrical matrix (citing versus cited) that is much more densely populated than the underlying matrix at the journal level. Exploratory factor analysis of the matrix of subject categories suggests a 14-factor solution. This solution could be interpreted as the disciplinary structure of science. The nested maps of science (corresponding to 14 factors, 172 categories, and 6,164 journals) are online at http://www.leydesdorff.net/map06. Presumably, inaccuracies in the attribution of journals to the ISI subject categories average out so that the factor analysis reveals the main structures. The mapping of science could, therefore, be comprehensive and reliable on a large scale albeit imprecise in terms of the attribution of journals to the ISI subject categories.
Themenfeld: Informetrie
Objekt: Map of Science ; Journal Citation Reports
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5Bensman, S.J.: Distributional differences of the impact factor in the sciences versus the social sciences : an analysis of the probabilistic structure of the 2005 journal citation reports.
In: Journal of the American Society for Information Science and Technology. 59(2008) no.9, S.1366-1382.
Abstract: This paper examines the probability structure of the 2005 Science Citation Index (SCI) and Social Sciences Citation Index (SSCI) Journal Citation Reports (JCR) by analyzing the Impact Factor distributions of their journals. The distribution of the SCI journals corresponded with a distribution generally modeled by the negative binomial distribution, whereas the SSCI distribution fit the Poisson distribution modeling random, rare events. Both Impact Factor distributions were positively skewed - the SCI much more so than the SSCI - indicating excess variance. One of the causes of this excess variance was that the journals highest in the Impact Factor in both JCRs tended to class in subject categories well funded by the National Institutes of Health. The main reason for the SCI Impact Factor distribution being more skewed than the SSCI one was that review journals defining disciplinary paradigms play a much more important role in the sciences than in the social sciences.
Themenfeld: Informetrie ; Citation indexing
Objekt: Science Citation Index ; Social Sciences Citation Index ; Journal Citation Reports
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6Chen, C.-M.: Classification of scientific networks using aggregated journal-journal citation relations in the Journal Citation Reports.
In: Journal of the American Society for Information Science and Technology. 59(2008) no.14, S.2296-2304.
Abstract: I propose an approach to classifying scientific networks in terms of aggregated journal-journal citation relations of the ISI Journal Citation Reports using the affinity propagation method. This algorithm is applied to obtain the classification of SCI and SSCI journals by minimizing intracategory journal-journal (J-J) distances in the database, where distance between journals is calculated from the similarity of their annual citation patterns with a cutoff parameter, t, to restrain the maximal J-J distance. As demonstrated in the classification of SCI journals, classification of scientific networks with different resolution is possible by choosing proper values of t. Twenty journal categories in SCI are found to be stable despite a difference of an order of magnitude in t. In our classifications, the level of specificity of a category can be found by looking at its value of RJ (the average distance of members of a category to its representative journal), and relatedness of category members is implied by the value of DJ-J (the average DJ-J distance within a category). Our results are consistent with the ISI classification scheme, and the level of relatedness for most categories in our classification is higher than their counterpart in the ISI classification scheme.
Themenfeld: Informetrie
Objekt: Journal Citation Reports
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7Leydesdorff, L.: Betweenness centrality as an indicator of the interdisciplinarity of scientific journals.
In: Journal of the American Society for Information Science and Technology. 58(2007) no.9, S.1303-1319.
Abstract: In addition to science citation indicators of journals like impact and immediacy, social network analysis provides a set of centrality measures like degree, betweenness, and closeness centrality. These measures are first analyzed for the entire set of 7,379 journals included in the Journal Citation Reports of the Science Citation Index and the Social Sciences Citation Index 2004 (Thomson ISI, Philadelphia, PA), and then also in relation to local citation environments that can be considered as proxies of specialties and disciplines. Betweenness centrality is shown to be an indicator of the interdisciplinarity of journals, but only in local citation environments and after normalization; otherwise, the influence of degree centrality (size) overshadows the betweenness-centrality measure. The indicator is applied to a variety of citation environments, including policy-relevant ones like biotechnology and nanotechnology. The values of the indicator remain sensitive to the delineations of the set because of the indicator's local character. Maps showing interdisciplinarity of journals in terms of betweenness centrality can be drawn using information about journal citation environments, which is available online.
Themenfeld: Informetrie
Objekt: Journal Citation Reports
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8Rousseau, R.: Timelines in citation research.
In: Journal of the American Society for Information Science and Technology. 57(2006) no.10, S.1404-1405.
(Brief communication)
Abstract: The timeline used in ISI's Journal Citation Reports (JCR; Thomson ISI, formerly the Institute for Scientific Information, Philadelphia, PA) for half-life calculations, is not a timeline for (average) cited age. These two timelines are shifted over half a year.
Themenfeld: Citation indexing
Objekt: Journal Citation Reports
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9Leydesdorff, L.: Clusters and maps of science journals based on bi-connected graphs in Journal Citation Reports.
In: Journal of documentation. 60(2004) no.4, S.371-427.
Abstract: The aggregated journal-journal citation matrix derived from Journal Citation Reports 2001 can be decomposed into a unique subject classification using the graph-analytical algorithm of bi-connected components. This technique was recently incorporated in software tools for social network analysis. The matrix can be assessed in terms of its decomposability using articulation points which indicate overlap between the components. The articulation points of this set did not exhibit a next-order network of "general science" journals. However, the clusters differ in size and in terms of the internal density of their relations. A full classification of the journals is provided in the Appendix. The clusters can also be extracted and mapped for the visualization.
Anmerkung: Vgl. auch unter: http://www.emeraldinsight.com/10.1108/00220410410548144.
Themenfeld: Citation indexing ; Informetrie
Objekt: Journal Citation Reports
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10Pudovkin, A.I. ; Garfield, E.: Algorithmic procedure for finding semantically related journals.
In: Journal of the American Society for Information Science and technology. 53(2002) no.13, S.1113-1119.
Abstract: Journal Citation Reports provides a classification of journals most heavily cited by a given journal and which most heavily cite that journal, but size variation is not taken into account. Pudovkin and Garfield suggest a procedure for meeting this difficulty. The relatedness of journal i to journal j is determined by the number of citations from journal i to journal j in a given year normalized by the product of the papers published in the j journal in that year times the number of references cited in the i journal in that year. A multiplier of ten to the sixth is suggested to bring the values into an easily perceptible range. While citations received depend upon the overall cumulative number of papers published by a journal, the current year is utilized since that data is available in JCR. Citations to current year papers would be quite low in most fields and thus not included. To produce the final index, the maximum of the A citing B value, and the B citing A value is chosen and used to indicate the closeness of the journals. The procedure is illustrated for the journal Genetics.
Themenfeld: Informetrie ; Citation indexing
Objekt: Journal Citation Reports
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11Stock, W.G.: Journal Citation Reports : Ein Impact Factor für Bibliotheken, Verlage und Autoren?.
In: Password. 2001, H.5, S.24-38.
Abstract: Gibt es objektive Kriterien für die Bestellung und Abbestellung wissenschaftlicher Zeitschriften? Wie lange sollte eine Bibliothek Periodikabestände benutzernah aufstellen? Kann ein Verlag -außer via Verkaufszahlen - auf Kriterien des Erfolgs seiner Zeitschriften zurückgreifen? Hat ein Autor eine Entscheidungsgrundlage, welcher Zeitschrift er seinen Artikel anbietet? Ist die Forschungsaktivität eines Instituts oder eines Wissenschaftlers über den Impact derjenigen Zeitschriftentitel zu evaluieren, die die Forschungsergebnisse drucken? Können die 'Journal Citation Reports (JCR) "des "Institute for Scientific Information" bei der Klärung solcher Fragen helfen? Sind die JCR ein nützliches oder gar ein notwendiges Hilfsmittel für Bibliotheken, für Verlage, für Wissenschaftsmanager und für wissenschaftliche Autoren? Die 'Journal Citation Reports" geben im Jahresrhythmus informetrische Kennzahlen wie die Zitationsrate, den Impact Factor, den Immediacy Index, die Halbwertszeit für eine Auswahl wissenschaftlicher Zeitschriften an. Zusätzlich berichten sie darüber, weiche Zeitschriften weiche anderen Zeitschriften zitieren bzw. von diesen zitiert werden, so dass "Soziogramme" wissenschaftlicher Zeitschriftenkommunikation entstehen. Wir wollen am Beispiel des aktuellen Jahrgangs ( 1999) die JCR detailliert beschreiben, die Auswahlkriterien der Zeitschriften beleuchten, die verwendeten informetrischen Kennwerte - vor allem den Impact Factor - kritisch hinterfragen, um danach die Einsatzgebiete bei Bibliotheken, in der Wissenschaftsevaluation, bei Verlagen und bei Autoren zu diskutieren. Das Fazit sei vorweggenommen: Die JCR sind ein nicht umgehbares Hilfsmittel für die fokussierten Anwendungsbereiche. Sie sind mitnichten frei von Problemen. Wir schließen daher mit einigen Verbesserungsvorschlägen
Themenfeld: Citation indexing ; Informetrie
Objekt: Journal Citation Reports
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12Kreider, J.: ¬The correlation of local citation data with citation data from Journal Citation Reports.
In: Library resources and technical services. 43(1999) no.2, S.67-77.
Abstract: University librarians continue to face the difficult task of determining which journals remain crucial for their collections during these times of static financial resources and escalating journal costs. One evaluative tool, Journal Citation Reports (JCR), recently has become available on CD-ROM, making it simpler for librarians to use its citation data as input for ranking journals. But many librarians remain unconvinced that the global citation data from the JCR bears enough correspondence to their local situation to be useful. In this project, I explore the correlation between global citation data available from JCR with local citation data generated specifically for the University of British Columbia, for 20 subject fields in the sciences and social sciences. The significant correlations obtained in this study suggest that large research-oriented university libraries could consider substituting global citation data for local citation data when evaluating their journals, with certain cautions.
Themenfeld: Informetrie
Objekt: Journal Citation Reports
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13Tsay, M.-Y.: From Science Citation Index to Journal Citation Reports, amd criteria for journals evaluation.
In: Journal of information; communication; and library science. 4(1997) no.2, S.27-41.
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
Anmerkung: In Chinesisch
Themenfeld: Citation indexing ; Informetrie
Objekt: Science Citation Index ; Journal Citation Reports
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14Magri, M. ; Solari, A.: ¬The SCI Journal Citation Reports : a potential tool for studying journals?.1. Description of the JCR journal population based on the number of citations received, number of source items, impact factor, immediacy index and cited half life.
In: Scientometrics. 35(1996) no.1, S.93-117.
Abstract: Analyses 6 indicators of the Science Citation Index Journals Citation Reports over a 19 year period: number of total citations, number of citations to the previous 2 years, number of source items, impact factor, immediacy index and cited half life. Proposes a box plot method to aggregate the values of each indicator so as to obtain at a glance portrayals of the JCR population from 1974 to 1993. This 'rereading' of the JCR, which presents the JCR product differently, makes it possible to shed new light on the large sub population of journals not at the top of the rankings
Themenfeld: Informetrie ; Citation indexing
Objekt: Journal Citation Reports