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Discontinuities in citation relations among journals: self-organized criticality as a model of scientific revolutions and change

Using 3-year moving averages of the complete Journal Citation Reports 1994–2016 of the Science Citation Index and the Social Sciences Citation Index (combined), we analyze links between citing and cited journals in terms of (1) whether discontinuities among the networks of consecutive years have occurred; (2) are these discontinuities relatively isolated or networked? (3) Can...

The geography of references in elite articles: Which countries contribute to the archives of knowledge?

: Lutz Bornmann, Caroline Wagner, Loet Leydesdorff. Data curation: Lutz Bornmann. Formal analysis: Lutz Bornmann. Investigation: Lutz Bornmann. Methodology: Lutz Bornmann. Writing ± original draft ... : Lutz Bornmann, Loet Leydesdorff. Writing ± review & editing: Caroline Wagner, Loet Leydesdorff. 12 / 14 13 / 14 1. Cole JR , Cole S . Social Stratification in Science. Chicago/ London: University of

Reference publication year spectroscopy (RPYS) of Eugene Garfield’s publications

Which studies, theories, and ideas have influenced Eugene Garfield’s scientific work? Recently, the method reference publication year spectroscopy (RPYS) has been introduced, which can be used to answer this and related questions. Since then, several studies have been published dealing with the historical roots of research fields and scientists. The program CRExplorer (http...

Measuring the expected synergy in Spanish regional and national systems of innovation

Amsterdam , The Netherlands 2 & Loet Leydesdorff This paper examines the effect of synergy at the geographical, technological, and organizational levels on the structure of the innovative system in Spain

Betweenness and diversity in journal citation networks as measures of interdisciplinarity—A tribute to Eugene Garfield

Journals were central to Eugene Garfield’s research interests. Among other things, journals are considered as units of analysis for bibliographic databases such as the Web of Science and Scopus. In addition to providing a basis for disciplinary classifications of journals, journal citation patterns span networks across boundaries to variable extents. Using betweenness centrality...

Mapping patent classifications: portfolio and statistical analysis, and the comparison of strengths and weaknesses

The Cooperative Patent Classifications (CPC) recently developed cooperatively by the European and US Patent Offices provide a new basis for mapping patents and portfolio analysis. CPC replaces International Patent Classifications (IPC) of the World Intellectual Property Organization. In this study, we update our routines previously based on IPC for CPC and use the occasion for...

“Open innovation” and “triple helix” models of innovation: can synergy in innovation systems be measured?

Leydesdorff 0 Inga Ivanova 0 Amsterdam School of Communication Research (ASCoR), University of Amsterdam , PO Box 15793, 1001, NG, Amsterdam , The Netherlands The model of “Open Innovations” (OI) can be

Generating clustered journal maps: an automated system for hierarchical classification

Journal maps and classifications for 11,359 journals listed in the combined Journal Citation Reports 2015 of the Science and Social Sciences Citation Indexes are provided at https://​leydesdorff.​github.​io/​journals/​ and http://​www.​leydesdorff.​net/​jcr15. A routine using VOSviewer for integrating the journal mapping and their hierarchical clusterings is also made available...

University-Industry Collaboration in China and the USA: A Bibliometric Comparison

In this study, university-industry collaborations in China and the USA are analyzed in terms of co-authored publications indexed in the Web of Science (WoS). Results show a wide gap between China and the USA: Chinese universities are much less active in collaborations with industry in terms of either publication productivity or collaboration intensity. In selecting local and...

Can technology life-cycles be indicated by diversity in patent classifications? The crucial role of variety

In a previous study of patent classifications in nine material technologies for photovoltaic cells, Leydesdorff et al. (Scientometrics 102(1):629–651, 2015) reported cyclical patterns in the longitudinal development of Rao–Stirling diversity. We suggested that these cyclical patterns can be used to indicate technological life-cycles. Upon decomposition, however, the cycles are...

Can intellectual processes in the sciences also be simulated? The anticipation and visualization of possible future states

Socio-cognitive action reproduces and changes both social and cognitive structures. The analytical distinction between these dimensions of structure provides us with richer models of scientific development. In this study, I assume that (1) social structures organize expectations into belief structures that can be attributed to individuals and communities; (2) expectations are...

Professional and citizen bibliometrics: complementarities and ambivalences in the development and use of indicators—a state-of-the-art report

Bibliometric indicators such as journal impact factors, h-indices, and total citation counts are algorithmic artifacts that can be used in research evaluation and management. These artifacts have no meaning by themselves, but receive their meaning from attributions in institutional practices. We distinguish four main stakeholders in these practices: (1) producers of bibliometric...

Cited references and Medical Subject Headings (MeSH) as two different knowledge representations: clustering and mappings at the paper level

For the biomedical sciences, the Medical Subject Headings (MeSH) make available a rich feature which cannot currently be merged properly with widely used citing/cited data. Here, we provide methods and routines that make MeSH terms amenable to broader usage in the study of science indicators: using Web-of-Science (WoS) data, one can generate the matrix of citing versus cited...

An evaluation of impacts in “Nanoscience & nanotechnology”: steps towards standards for citation analysis

Loet Leydesdorff 0 0 L. Leydesdorff (&) Amsterdam School of Communications Research (ASCoR), University of Amsterdam , Kloveniersburgwal 48, 1012 CX Amsterdam, The Netherlands One is inclined to

Alternatives to the journal impact factor: I3 and the top-10% (or top-25%?) of the most-highly cited papers

Journal impact factors (IFs) can be considered historically as the first attempt to normalize citation distributions by using averages over 2 years. However, it has been recognized that citation distributions vary among fields of science and that one needs to normalize for this. Furthermore, the mean—or any central-tendency statistics—is not a good representation of the citation...

Sociological and Communication-Theoretical Perspectives on the Commercialization of the Sciences

Loet Leydesdorff 0 0 L. Leydesdorff (&) Amsterdam School of Communication Research (ASCoR), University of Amsterdam , Kloveniersburgwal 48, 1012 CX Amsterdam, The Netherlands Both self-organization

The Continuing Growth of Global Cooperation Networks in Research: A Conundrum for National Governments

Global collaboration continues to grow as a share of all scientific cooperation, measured as coauthorships of peer-reviewed, published papers. The percent of all scientific papers that are internationally coauthored has more than doubled in 20 years, and they account for all the growth in output among the scientifically advanced countries. Emerging countries, particularly China...

How have the Eastern European countries of the former Warsaw Pact developed since 1990? A bibliometric study

Did the demise of the Soviet Union in 1991 influence the scientific performance of the researchers in Eastern European countries? Did this historical event affect international collaboration by researchers from the Eastern European countries with those of Western countries? Did it also change international collaboration among researchers from the Eastern European countries...

Macro-Indicators of Citation Impacts of Six Prolific Countries: InCites Data and the Statistical Significance of Trends

Using the InCites tool of Thomson Reuters, this study compares normalized citation impact values calculated for China, Japan, France, Germany, United States, and the UK throughout the time period from 1981 to 2010. InCites offers a unique opportunity to study the normalized citation impacts of countries using (i) a long publication window (1981 to 2010), (ii) a differentiation in...