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  • Author or Editor: Loet Leydesdorff x
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Abstract

Citation distributions are so skewed that using the mean or any other central tendency measure is ill-advised. Unlike G. Prathap's scalar measures (Energy, Exergy, and Entropy or EEE), the Integrated Impact Indicator (I3) is based on non-parametric statistics using the (100) percentiles of the distribution. Observed values can be tested against expected ones; impact can be qualified at the article level and then aggregated.

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Abstract

In reaction to a previous critique (Opthof and Leydesdorff, J Informetr 4(3):423–430, 2010), the Center for Science and Technology Studies (CWTS) in Leiden proposed to change their old “crown” indicator in citation analysis into a new one. Waltman (Scientometrics 87:467–481, 2011a) argue that this change does not affect rankings at various aggregated levels. However, CWTS data is not publicly available for testing and criticism. Therefore, we comment by using previously published data of Van Raan (Scientometrics 67(3):491–502, 2006) to address the pivotal issue of how the results of citation analysis correlate with the results of peer review. A quality parameter based on peer review was neither significantly correlated with the two parameters developed by the CWTS in the past citations per paper/mean journal citation score (CPP/JCSm) or CPP/FCSm (citations per paper/mean field citation score) nor with the more recently proposed h-index (Hirsch, Proc Natl Acad Sci USA 102(46):16569–16572, 2005). Given the high correlations between the old and new “crown” indicators, one can expect that the lack of correlation with the peer-review based quality indicator applies equally to the newly developed ones.

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Abstract  

University patenting has been heralded as a symbol of changing relations between universities and their social environments. The Bayh–Dole Act of 1980 in the USA was eagerly promoted by the OECD as a recipe for the commercialization of university research, and the law was imitated by a number of national governments. However, since the 2000s university patenting in the most advanced economies has been on the decline both as a percentage and in absolute terms. In addition to possible saturation effects and institutional learning, we suggest that the institutional incentives for university patenting have disappeared with the new regime of university ranking. Patents and spin-offs are not counted in university rankings. In the new arrangements of university–industry–government relations, universities have become very responsive to changes in their relevant environments.

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Abstract  

This research analyzes a “who cites whom” matrix in terms of aggregated journal-journal citations to determine the location of communication studies on the academic spectrum. Using the Journal of Communication as the seed journal, the 2006 data in the Journal Citation Reports are used to map communication studies. The results show that social and experimental psychology journals are the most frequently used sources of information in this field. In addition, several journals devoted to the use and effects of media and advertising are weakly integrated into the larger communication research community, whereas communication studies are dominated by American journals.

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Abstract

The Leiden ranking 2011/2012 provides the Proportion top-10% publications (PP top-10% ) as a new indicator. This indicator allows for testing performance differences between two universities for statistical significance.

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Abstract  

This article explores the emergence of knowledge from scientific discoveries and their effects on the structure of scientific communication. Network analysis is applied to understand this emergence institutionally as changes in the journals; semantically as changes in the codification of meaning in terms of words; and cognitively as the new knowledge becomes the emergent foundation of further developments. The discovery of fullerenes in 1985 is analyzed as the scientific discovery that triggered a process which led to research in nanotubes.

Open access
Scientometrics
Authors:
Loet Leydesdorff
,
Virginia Trimnle
, and
Péter Vinkler
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Abstract  

We present a model to assess the systemness of an innovation system. Patent and citation datawith an institutional address in Catalonia (1986-1996) were analyzed in terms of relationallinkages and the development in these distributions over time was evaluated using methods fromsystems dynamics. Relational linkages are extremely scarce. A transition at the system's levelcould be indicated around 1990 when using institutional addresses, but not when using cognitivecategories. The institutional restructuring has led to changes in the pattern of linkages(coauthorship, etc.), but the reproduction of the system's knowledge base has remaineddifferentiated. We conclude that although a system in several other respects, Catalonia cannot(yet) be considered as a (knowledge-based) innovation system. The existence of a mechanism forthe integration could not be indicated at the regional level.

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Summary This paper elaborates on the Triple Helix model for measuring the emergence of a knowledge base of socio-economic systems. The ‘knowledge infrastructure’ is measured using multiple indicators: webometric, scientometric, and technometric. The paper employs this triangulation strategy to examine the current state of the innovation systems of South Korea and the Netherlands. These indicators are thereafter used for the evaluation of the systemness in configurations of university-industry-government relations. South Korea is becoming somewhat stronger than the Netherlands in terms of scientific and technological outputs and in terms of the knowledge-based dynamics; South Korea’s portfolio is more traditional than that of the Netherlands. For example, research and patenting in the biomedical sector is underdeveloped. In terms of the Internet-economy, the Netherlands seem oriented towards global trends more than South Korea; this may be due to the high component of services in the Dutch economy.

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Abstract

We trace the structural patterns of co-authorship between Korean researchers at three institutional types (university, government, and industry) and their international partners in terms of the mutual information generated in these relations. Data were collected from the Web of Science during the period 1968–2009. The traditional Triple-Helix indicator was modified to measure the evolving network of co-authorship relations. The results show that international co-authorship relations have varied considerably over time and with changes in government policies, but most relations have become stable since the early 2000s. In other words, the national publication system of Korea has gained some synergy from R&D internationalization during the 1990s, but the development seems to stagnate particularly at the national level: whereas both university and industrial collaborations are internationalized, the cross-connection within Korea has steadily eroded.

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