Search (271 results, page 1 of 14)

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Abstract

A similarity-oriented approach for deriving reference values used in citation normalization is explored and contrasted with the dominant approach of utilizing database-defined journal sets as a basis for deriving such values. In the similarity-oriented approach, an assessed article's raw citation count is compared with a reference value that is derived from a reference set, which is constructed in such a way that articles in this set are estimated to address a subject matter similar to that of the assessed article. This estimation is based on second-order similarity and utilizes a combination of 2 feature sets: bibliographic references and technical terminology. The contribution of an article in a given reference set to the reference value is dependent on its degree of similarity to the assessed article. It is shown that reference values calculated by the similarity-oriented approach are considerably better at predicting the assessed articles' citation count compared to the reference values given by the journal-set approach, thus significantly reducing the variability in the observed citation distribution that stems from the variability in the articles' addressed subject matter.

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Abstract

This article uses an evidence-based approach to assess the difficulties faced by developing country scientists in accessing scientific literature. I compare the backward citation patterns of Swiss and Indian scientists in a database of 43,150 scientific papers published by scientists from either country in 2007. Controlling for fields and quality with citing journal fixed effects, I find that Indian scientists have shorter reference lists (-6%) and are more likely to cite articles from open access journals (+50%). Moreover, the difference in the length of the reference list is more pronounced in biology and medicine, where circulation of (free) preprints and conference proceedings is non-existent. Informal file-sharing practices among scientists mitigate the effects of access restrictions.

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Abstract

This paper evaluates the content of Google Scholar and seven other databases (Academic Search Elite, AgeLine, ArticleFirst, GEOBASE, POPLINE, Social Sciences Abstracts, and Social Sciences Citation Index) within the multidisciplinary subject area of later-life migration. Each database is evaluated with reference to a set of 155 core articles selected in advance-the most important studies of later-life migration published from 1990 to 2000. Of the eight databases, Google Scholar indexes the greatest number of core articles (93%) and provides the most uniform publisher and date coverage. It covers 27% more core articles than the second-ranked database (SSCI) and 2.4 times as many as the lowest-ranked database (GEOBASE). At the same time, a substantial proportion of the citations provided by Google Scholar are incomplete (32%) or presented without abstracts (33%).

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Abstract

Presents a list of 53 periodicals in 22 subject fields which regularly provide bibliographies of theses, research in progress and patents in their particular subject field. The fields of business, economics, history and literature have most periodical listings of dissertations and theses. Also lists 63 periodicals in 25 sub-disciplines which provide rankings or ratings. Rankings and ratings information predominates in the fields of business, sports and games, finance and banking, and library and information science

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Abstract

This work identifies and analyzes literature about knowledge organization (KO), expressed in scientific journals' communication of information science (IS). It performs an exploratory study on the Base de Dados Referencial de Artigos de Periódicos em Ciência da Informação (BRAPCI, Reference Database of Journal Articles on Information Science) between the years 2000 and 2010. The descriptors relating to "knowledge organization" are used in order to recover and analyze the corresponding articles and to identify descriptors and concepts which integrate the semantic universe related to KO. Through the analysis of content, based on metrical studies, this article gathers and interprets data relating to documents and authors. Through this, it demonstrates the development of this field and its research fronts according to the observed characteristics, as well as noting the transformation indicative in the production of knowledge. The work describes the influences of the Spanish researchers on Brazilian literature in the fields of knowledge and information organization. As a result, it presents the most cited and productive authors, the theoretical currents which support them, and the most significant relationships of the Spanish-Brazilian authors network. Based on the constant key-words analysis in the cited articles, the co-existence of the French conception current and the incipient Spanish influence in Brazil is observed. Through this, it contributes to the comprehension of the thematic range relating to KO, stimulating both criticism and self-criticism, debate and knowledge creation, based on studies that have been developed and institutionalized in academic contexts in Spain and Brazil.

Content

Beitrag einer Section "Selected Papers from the 1ST Brazilian Conference on Knowledge Organization And Representation, Faculdade de Ciência da Informação, Campus Universitário Darcy Ribeiro Brasília, DF Brasil, October 20-22, 2011" Vgl.: http://www.ergon-verlag.de/isko_ko/downloads/ko_39_2012_3_g.pdf.

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Abstract

Although it is commonly expected that the citation context of a reference is likely to provide more detailed and direct information about the nature of a citation, few studies in the literature have specifically addressed the extent to which the information in different parts of a scientific publication differs. Do abstracts tend to use conceptually broader terms than sentences in a citation context in the body of a publication? In this article, we propose a method to analyze and compare latent topics in scientific publications, in particular, from abstracts of papers that cited a target reference and from sentences that cited the target reference. We conducted an experiment and applied topical modeling techniques to full-text papers in eight biomedicine journals. Topics derived from the two sources are compared in terms of their similarities and broad-narrow relationships defined based on information entropy. The results show that abstracts and citation contexts are characterized by distinct sets of topics with moderate overlaps. Furthermore, the results confirm that topics from abstracts of citing papers have broader terms than topics from citation contexts formed by citing sentences. The method and the findings could be used to enhance and extend the current methodologies for research evaluation and citation evaluation.

Date

22. 3.2013 19:50:00

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Abstract

Citation analysis has long been used by librarians as an important tool of collection development and the advent of Internet technology and especially the WWW adds a new facet to the role played by citation analysis. One of the reasons why librarians create WWW homepages is to provide users with further sources of interest or reference and to do this libraries include links from their own homepages to other information sources. Reports current research on the analysis of WWW pages as an introduction to an examination of the homepages of 25 art libraries to determine what sites are most often included. The types of linked sites are analyzed based on 3 criteria: location, focus and evidence that the link was evaluated before the connection was establisheds

Date

10. 1.1999 16:22:37

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Abstract

Purpose Chemical databases have had a significant impact on the way scientists search for and use information. The purpose of this paper is to spark informed discussion and fuel debate on the issue of citations to chemical databases. Design/methodology/approach A citation analysis to four major chemical databases was undertaken to examine resource coverage and impact in the scientific literature. Two commercial databases (SciFinder and Reaxys) and two public databases (PubChem and ChemSpider) were analyzed using the "Cited Reference Search" in the Science Citation Index Expanded from the Web of Science (WoS) database. Citations to these databases between 2000 and 2016 (inclusive) were evaluated by document types and publication growth curves. A review of the distribution trends of chemical databases in peer-reviewed articles was conducted through a citation count analysis by country, organization, journal and WoS category. Findings In total, 862 scholarly articles containing a citation to one or more of the four databases were identified as only steadily increasing since 2000. The study determined that authors at academic institutions worldwide reference chemical databases in high-impact journals from notable publishers and mainly in the field of chemistry. Originality/value The research is a first attempt to evaluate the practice of citation to major chemical databases in the scientific literature. This paper proposes that citing chemical databases gives merit and recognition to the resources as well as credibility and validity to the scholarly communication process and also further discusses recommendations for citing and referencing databases.

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Abstract

We present a novel routine, namely medlineR, based on the R language, that allows the user to match data from Medline/PubMed with records indexed in the ISI Web of Science (WoS) database. The matching allows exploiting the rich and controlled vocabulary of medical subject headings (MeSH) of Medline/PubMed with additional fields of WoS. The integration provides data (e.g., citation data, list of cited reference, list of the addresses of authors' host organizations, WoS subject categories) to perform a variety of scientometric analyses. This brief communication describes medlineR, the method on which it relies, and the steps the user should follow to perform the matching across the two databases. To demonstrate the differences from Leydesdorff and Opthof (Journal of the American Society for Information Science and Technology, 64(5), 1076-1080), we conclude this artcle by testing the routine on the MeSH category "Burgada syndrome."

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Abstract

Normalization of citation scores using reference sets based on Web of Science subject categories (WCs) has become an established ("best") practice in evaluative bibliometrics. For example, the Times Higher Education World University Rankings are, among other things, based on this operationalization. However, WCs were developed decades ago for the purpose of information retrieval and evolved incrementally with the database; the classification is machine-based and partially manually corrected. Using the WC "information science & library science" and the WCs attributed to journals in the field of "science and technology studies," we show that WCs do not provide sufficient analytical clarity to carry bibliometric normalization in evaluation practices because of "indexer effects." Can the compliance with "best practices" be replaced with an ambition to develop "best possible practices"? New research questions can then be envisaged.

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Abstract

Empirical studies of obliteration by incorporation (OBI) may be conducted at the level of the database record or the fulltext citation-in-context. To assess the difference between the two approaches, 1,040 articles with a variant of the phrase "evolutionarily stable strategies" (ESS) were identified by searching the Web of Science (Thomson Reuters, Philadelphia, PA) and discipline-level databases. The majority (72%) of all articles were published in life sciences journals. The ESS concept is associated with a small set of canonical publications by John Maynard Smith; OBI represents a decoupling of the use of the phrase and a citation to a John Maynard Smith publication. Across all articles at the record level, OBI is measured by the number of articles with the phrase in the database record but which lack a reference to a source article (implicit citations). At the citation-in-context level, articles that coupled a non-Maynard Smith citation with the ESS phrase (indirect citations) were counted along with those that cited relevant Maynard Smith publications (explicit citations) and OBI counted only based on those articles that lacked any citation coupled with the ESS text phrase. The degree of OBI observed depended on the level of analysis. Record-level OBI trended upward, peaking in 2002 (62%), with a secondary drop and rebound to 53% (2008). Citation-in-context OBI percentages were lower with no clear pattern. Several issues relating to the design of empirical OBI studies are discussed.

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Abstract

The reference lists of forty-three education dissertations on curriculum and instruction completed at the University of Minnesota during the calendar years 2000-2002 were analyzed to inform collection development. As one measure of use of the academic library collection, the citation analysis yielded data to guide journal selection, retention, and cancellation decisions. The project aimed to ensure that the most frequently cited journals were retained on subscription. The serial monograph ratio for citation also was evaluated in comparison with other studies and explored in the context of funding ratios. Results of citation studies can provide a basis for liaison conversations with faculty in addition to guiding selection decisions. This research project can serve as a model for similar projects in other libraries that look at literature in education as well as other fields.

Date

10. 9.2000 17:38:22

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Abstract

The bibliometric measure impact factor is a leading indicator of journal influence, and impact factors are routinely used in making decisions ranging from selecting journal subscriptions to allocating research funding to deciding tenure cases. Yet journal impact factors have increased gradually over time, and moreover impact factors vary widely across academic disciplines. Here we quantify inflation over time and differences across fields in impact factor scores and determine the sources of these differences. We find that the average number of citations in reference lists has increased gradually, and this is the predominant factor responsible for the inflation of impact factor scores over time. Field-specific variation in the fraction of citations to literature indexed by Thomson Scientific's Journal Citation Reports is the single greatest contributor to differences among the impact factors of journals in different fields. The growth rate of the scientific literature as a whole, and cross-field differences in net size and growth rate of individual fields, have had very little influence on impact factor inflation or on cross-field differences in impact factor.

Date

23. 2.2009 18:22:28

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Date

22. 3.2009 19:05:07

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Abstract

This article studies massive evidence about references made and citations received after a 5-year citation window by 3.7 million articles published in 1998 to 2002 in 22 scientific fields. We find that the distributions of references made and citations received share a number of basic features across sciences. Reference distributions are rather skewed to the right while citation distributions are even more highly skewed: The mean is about 20 percentage points to the right of the median, and articles with a remarkable or an outstanding number of citations represent about 9% of the total. Moreover, the existence of a power law representing the upper tail of citation distributions cannot be rejected in 17 fields whose articles represent 74.7% of the total. Contrary to the evidence in other contexts, the value of the scale parameter is above 3.5 in 13 of the 17 cases. Finally, power laws are typically small, but capture a considerable proportion of the total citations received.

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Abstract

The term author co-citation is defined and classified according to four distinct forms: the pure first-author co-citation, the pure author co-citation, the general author co-citation, and the special co-authorlco-citation. Each form can be used to obtain one count in an author co-citation study, based an a binary counting rule, which either recognizes the co-citedness of two authors in a given reference list (1) or does not (0). Most studies using author co-citations have relied solely an first-author cocitation counts as evidence of an author's oeuvre or body of work contributed to a research field. In this article, we argue that an author's contribution to a selected field of study should not be limited, but should be based an his/her complete list of publications, regardless of author ranking. We discuss the implications associated with using each co-citation form and show where simple first-author co-citations fit within our classification scheme. Examples are given to substantiate each author co-citation form defined in our classification, including a set of sample Dialog(TM) searches using references extracted from the SciSearch database.

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Abstract

This study is concerned with differences in referencing patterns between book literature and periodical publications. Four indicators, the mean reference rate per page, the percentage of references to Web of Science journal literature, the mean reference age, and Price Index, were applied to analyze the reference patterns of three publication types: books, book chapter articles and journal articles. References of publications indexed in Web of Science Core Collection were analyzed for two periods (2005-2009, 2010-2013) and across 15 disciplines. Journal article authors cite more recent references and more references from serial publications than monograph authors. The difference between the sciences and the SSH is as obvious as the difference between periodical and non-serial publications. However, the reference patterns of social sciences are much more similar to science fields than humanities, especially for monographs. The subject characteristics of reference pattern are strongly affected by publication types. Furthermore, journal publications have stronger associations between ageing indicators and the share of WoS journal references than monographs.

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Abstract

In this study, reference standards and reference multipliers are suggested as a means to compare the citation impact of earlier research publications in physics (from the period of "Little Science" in the early 20th century) with that of contemporary papers (from the period of "Big Science," beginning around 1960). For the development of time-specific reference standards, the authors determined (a) the mean citation rates of papers in selected physics journals as well as (b) the mean citation rates of all papers in physics published in 1900 (Little Science) and in 2000 (Big Science); this was accomplished by relying on the processes of field-specific standardization in bibliometry. For the sake of developing reference multipliers with which the citation impact of earlier papers can be adjusted to the citation impact of contemporary papers, they combined the reference standards calculated for 1900 and 2000 into their ratio. The use of reference multipliers is demonstrated by means of two examples involving the time adjusted h index values for Max Planck and Albert Einstein.

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Abstract

Um sich einer Antwort auf die Frage anzunähern, welche Bedeutung der Nachlass eines Wissenschaftlers wie jener Paul F. Lazarsfelds (mit zahlreichen noch unveröffentlichten Schriften) für die aktuelle Forschung haben könne, kann untersucht werden, wie häufig dieser Wissenschaftler zitiert wird. Wenn ein Autor zitiert wird, wird er auch genutzt. Wird er über einen langen Zeitraum oft genutzt, ist vermutlich auch die Auseinandersetzung mit seinem Nachlass von Nutzen. Außerdem kann aufgrund der Zitierungen festgestellt werden, was aus dem Lebenswerk eines Wissenschaftlers für die aktuelle Forschung relevant erscheint. Daraus können die vordringlichen Fragestellungen in der Bearbeitung des Nachlasses abgeleitet werden. Die Aufgabe für die folgende Untersuchung lautete daher: Wie oft wird Paul F. Lazarsfeld zitiert? Dabei interessierte auch: Wer zitiert wo? Die Untersuchung wurde mit Hilfe der Meta-Datenbank "ISI Web of Knowledge" durchgeführt. In dieser wurde im "Web of Science" mit dem Werkzeug "Cited Reference Search" nach dem zitierten Autor (Cited Author) "Lazarsfeld P*" gesucht. Diese Suche ergab 1535 Referenzen (References). Werden alle Referenzen gewählt, führt dies zu 4839 Ergebnissen (Results). Dabei wurden die Datenbanken SCI-Expanded, SSCI und A&HCI verwendet. Bei dieser Suche wurden die Publikationsjahre 1941-2008 analysiert. Vor 1956 wurden allerdings nur sehr wenige Zitate gefunden: 1946 fünf, ansonsten maximal drei, 1942-1944 und 1949 überhaupt keines. Zudem ist das Jahr 2008 noch lange nicht zu Ende. (Es gab jedoch schon vor Ende März 24 Zitate!)

Date

22. 6.2008 12:54:12

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Abstract

Main path analysis is a powerful tool for extracting the backbones of a directed network and has been applied widely in bibliometric studies. In contrast to the no-decay assumption in the traditional approach, this study proposes a novel technique by assuming that the strength of knowledge decays when knowledge contained in one document is passed on to another document down the citation chain. We propose three decay models, arithmetic decay, geometric decay, and harmonic decay, along with their theoretical properties. In general, results of the proposed decay models depend largely on the local structure of a citation network as opposed to the global structure in the traditional approach. Thus, the significance of citation links and the associated documents that are overemphasized by the global structure in the traditional no-decay approach is treated more properly. For example, the traditional approach commonly assigns high value to documents that heavily reference others, such as review articles. Specifically in the geometric and harmonic decay models, only truly significant review articles will be included in the resulting main paths. We demonstrate this new approach and its properties through the DNA literature citation network.

Date

22. 1.2016 14:23:00