Loet Leydesdorff

Loet Leydesdorff
University of Amsterdam | UVA · Amsterdam School of Communications Research ASCoR

PhD

About

771
Publications
318,912
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Introduction
Loet Leydesdorff is Professor at the Amsterdam School of Communications Research (ASCoR) of the University of Amsterdam. He is Honorary Professor of the Science and Technology Policy Research Unit (SPRU) of the University of Sussex, Visiting Professor of the Institute of Scientific and Technical Information of China (ISTIC) in Beijing, Guest Professor at Zhejiang University in Hangzhou, and Visiting Professor at the School of Management, Birkbeck, University of London. http://www.leydesdorff.net

Publications

Publications (771)
Article
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In the original Triple Helix model (Etzkowitz and Leydesdorff 1995), the three “helices” of Universities, Industry and Government and the (3-way) interactions among and between them were proposed as a basis for looking at how entrepreneurship comes into being. Since the original article, other “helix-based” models have been proposed. Some vary the...
Article
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Carayannis and Campbell (2009; 2010) have argued for using quadruple and quintuple helices as models encompassing and generalizing triple-helix dynamics. In the meantime, quadruple and quintuple helices have been adopted by the European Committee for the Regions and the European Commission as metaphors for further strategy development such as in EU...
Article
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The top-1% most-highly-cited articles are watched closely as the vanguards of the sciences. Using Web of Sciencee data, one can find that China had overtaken the USA in the relative participation in the top-1% (PP-top1%) in 2019, after outcompeting the EU on this indicator in 2015. However, this finding contrasts with repeated reports of Western ag...
Preprint
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The top 1 percent most highly cited articles are watched closely as the vanguards of the sciences. Using Web of Science data, one can find that China had overtaken the USA in the relative participation in the top 1 percent in 2019, after outcompeting the EU on this indicator in 2015. However, this finding contrasts with repeated reports of Western...
Article
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Science and technology develop not only along historical trajectories, but also as next-order regimes that periodically change the landscape. Regimes can incur on trajectories which are then disrupted. Using citations and references for the operationalization, we discuss and quantify both the recently proposed “disruption indicator” and the older i...
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Purpose Interdisciplinarity is a hot topic in science and technology policy. However, the concept of interdisciplinarity is both abstract and complex, and therefore difficult to measure using a single indicator. A variety of metrics for measuring the diversity and interdisciplinarity of articles, journals, and fields have been proposed in the liter...
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Our previous mapping technique of the journal set included in the Journal Citation Reports (JCRs) is further elaborated into sophisticated computer routines.
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Purpose Building on Leydesdorff, Bornmann, and Mingers (2019), we elaborate the differences between Tsinghua and Zhejiang University as an empirical example. We address the question of whether differences are statistically significant in the rankings of Chinese universities. We propose methods for measuring statistical significance among different...
Article
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The disruption index (DI) based on bibliographic coupling and uncoupling between a document and its references was first proposed by Funk & Owen-Smith (2017) for citation relations among patents and then adapted for scholarly papers by Wu et al. (2019). However, Wu & Wu (2019) argued that this indicator would be inconsistent. We propose revised dis...
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Tools for Smart Specialisation Strategy (RIS3) development to assess at which territorial level innovation is concentrated and how innovation systems compare across regions and sectors remain scarce. The triple helix indicator is a data-driven tool that can serve in RIS3 development to assess synergy in innovation systems based on readily available...
Chapter
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Das Buch The Computer and the Brain (1958, dt. 1991; im Folgenden wird nach der deutschen Übersetzung zitiert) ist die gedruckte Version der Silliman Lectures, die zu halten John von Neumann 1956 nach Yale eingeladen worden war. Obwohl sie bis zum März 1956 vorbereitet waren, wurden sie nie gehalten, da von Neumann zu dieser Zeit bereits zu krank w...
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The operationalization of socio-cognitive structures in terms of observables such as texts (e.g., in discourse analysis and scientometrics) or the behavior of agents (e.g., in the sociology of scientific knowledge) may inadvertedly lead to reification. The dynamics of knowledge are not directly observable, but knowledge contents can be reconstructe...
Chapter
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Three themes have been central to my research program: (1) the dynamics of science, tech-nology, and innovation; (2) the scientometric operationalization and measurement of these dynamics; and (3) the Triple Helix (TH) of university-industry-government relations. In this introductory chapter, I relate these three themes first from an autobiographic...
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Although there is no necessary relation between “big data” and “monism”—the program of reducing cultural and mental processes to computational and biological principles—both these programs reject a dualism between res extensa and res cogitans. Opposing this philosophy of science, I have argued in the above chapter that a second contingency of possi...
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Using firm-level data collected by Statistics Italy for 2008, 2011, and 2015, the Triple-Helix synergy among geographical and size distributions of firms and technology classes is analyzed both regionally and nationally. The Italian system is both knowledge-based and knowledge-intensive, and therefore an interesting case. The contributions to natio...
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Using a set of six equations, I propose to model “interactions,” the “organization of meaning,” and “self-organization” as three coordination mechanisms among expectations; three further equations can be derived to operationalize “double contingency,” “identity,” and “reflection.” One can expect that the subdynamics update one another in co-evoluti...
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Whereas knowledge has often been attributed to individuals or, from a sociological perspective, to communities, a communications perspective on the sciences enables us to proceed to the measurement of the discursive knowledge contents. Knowledge claims are organized into texts which are entrained in evolving structures. The aggregated citation rela...
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In this chapter, I extend Shannon’s linear model of communication into a model in which communication is differentiated both vertically and horizontally (Simon, 1973). Following Weaver (1949), three layers are distinguished operating in relation to one another: ( i ) at level A, the events are sequenced historically along the arrow of time, generat...
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In the sociology of scientific knowledge and the sociology of translation, heterogeneous networks have been studied in terms of practices and so-called actor-networks . However, scientific practices are intellectually structured by codes. Cognitive structures interact and co-construct the organization of scholars and discourses into research progra...
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When policy-makers call for “interdisciplinarity,” they often mean “synergy.” Problem-solving requires crossing boundaries, such as those between disciplines. However, synergy can also be generated ininter-sectorial or geographical collaborations. Synergy is indicated when the whole offers more possibilities than the sum of its parts; “interdiscipl...
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Full-text available
Three themes have been central to my research program: (1) the dynamics of science, technology, and innovation; (2) the scientometric operationalization and measurement of these dynamics; and (3) the Triple Helix (TH) of university-industry-government relations. University-industry-government relations provide an institutional infrastructure carryi...
Book
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This open access book have three themes have been central to Leydesdorff's research: (1) the dynamics of science, technology, and innovation; (2) the scientometric operationalization of these concept; and (3) the elaboration in terms of a Triple Helix of university-industry-government relations. In this study, I discuss the relations among these th...
Chapter
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The institutional TH model focuses on relations of universities, industries, and governments in networks. Institutional arrangements develop over time along trajectories. The Triple-Helix metaphor of university-industry-government relations can also be elaborated into a neo-evolutionary model combining the vertical differentiation among the levels...
Chapter
Das Buch The Computer and the Brain (1958, dt. 1991; im Folgenden wird nach der deutschen Übersetzung zitiert) ist die gedruckte Version der Silliman Lectures, die zu halten John von Neumann 1956 nach Yale eingeladen worden war. Obwohl sie bis zum März 1956 vorbereitet waren, wurden sie nie gehalten, da von Neumann zu dieser Zeit bereits zu krank w...
Preprint
Full-text available
Purpose: We address the question of whether differences are statistically significant in the rankings of universities. We propose methods measuring the statistical significance among different universities and illustrate the results by empirical data. Design/methodology/approach: Based on z-testing and overlapping confidence intervals, and using da...
Article
Full-text available
Problem solving often requires crossing boundaries, such as those between disciplines. When policy‐makers call for “interdisciplinarity,” however, they often mean “synergy.” Synergy is generated when the whole offers more possibilities than the sum of its parts. An increase in the number of options above the sum of the options in subsets can be mea...
Article
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We elaborate Alfred Schutz's theory of musical communication empirically. Our technique for analysing musical communication aligns Schutz's sociological theory with the mathematics of anticipatory systems. Music, we argue, can be considered as an anticipatory system that articulates through its diachronic unfolding, fundamental symmetries which can...
Article
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Double contingency—each of us (Ego) expects others (Alter) to entertain expectations as we entertain them ourselves—can be considered as the micro-operation of an above-individual (i.e., social) logic of expectations. Meaning is provided to events from the perspective of hindsight, but with reference to horizons of meaning. Whereas “natural selecti...
Article
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In this note, we explain how to find the yearly numbers of items in Clarivate's Web of Science (WoS) and its sub-databases. As a result, we find that the WoS Core Collection grows exponentially during the period 1990-2019. We check and confirm that a simultaneous search at different locations leads to exactly the same results.
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Purpose In recent years, one can witness a trend in research evaluation to measure the impact on society or attention to research by society (beyond science). We address the following question: can Twitter be meaningfully used for the mapping of public and scientific discourses? Design/methodology/approach Recently, Haunschild et al. (2019) introd...
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Judit Bar-Ilan (JB) was an influential researcher in information science and scientometrics. She published more than 100 papers about different topics. We used the CRExplorer (see www.crexplorer.net) to investigate the historical roots of JB’s research. In this program, the N_TOP10 indicator is available. We applied this indicator to identify those...
Article
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Both “interdisciplinarity” and “synergy” are desirable features from a policy perspective: can surplus be found in the interactions among (disciplinary) bodies of knowledge? We have recently developed measures for “interdisciplinarity” and distinguished these measurements from those of “synergy.” In this study, we analyze three review papers by Jud...
Article
What are the landmark papers in scientific disciplines? Which papers are indispensable for scientific progress? These are typical questions which are of interest not only for researchers (who frequently know the answers – or guess to know them) but also for the interested general public. Citation counts can be used to identify very useful papers si...
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Patents relate the scientific, technological, and business dimensions of eco-systems. Based on the number of references to patents aggregated at the level of journals, we map two indicators of linkages between the sciences and technologies: patent intensity (PI) and patent density (PD). Journal maps can be overlaid with the values of PD and PI so t...
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We propose the Modified Economic Complexity Index (MECI) as a possible refinement to two relevant complexity measures: the Economic Complexity index (ECI) and the Fitness and Complexity index (FCI). Both ECI and FCI are used for the evaluation of competitive advantages and growth potentials of countries. ECI and FCI assume bipartite country-network...
Article
The Journal Impact Factor (JIF) is linearly sensitive to self-citations because each self-citation adds to the numerator, whereas the denominator is not affected. Pinski and Narin (1976) Influence Weights (IW) are not or marginally sensitive to these outliers on the main diagonal of a citation matrix and thus provide an alternative to JIFs. Whereas...
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Employing a quantitative, data-driven tool - the Triple Helix Indicator - to microdata of firms in Germany, we develop an evidence base for innovation-policy strategies. We aim to answer the question which level of government (local, regional, national) might be most effective for strategic innovation policy-making based on smart specialization in...
Article
Full-text available
Double contingency—each of us (Ego) expects others (Alter) to entertain expectations as we entertain them ourselves—can be considered as the micro-operation of an above-individual (i.e., social) logic of expectations. Meaning is provided to events from the perspective of hindsight, but with reference to horizons of meaning. Whereas “natural selecti...
Article
Full-text available
The sciences develop as conglomerates of ideas, texts, and agents. In this study, we propose a n-mode network approach to integrate the network matrices containing social, semantic, and epistemic attributes analytically into a single network and visualization. For example, authors, words (e.g., title words and keywords), and knowledge claims can be...
Article
Innovative economies generate new options from geographical, technological, and organizational synergies. These synergies can be indicated as subsystems of negative entropy. Such a reduction of uncertainty favours the climate for innovation. Using information theory and triple helix model of university-industry-government relations, we analyse the...
Article
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One can use the Leiden Rankings for grouping research universities by considering universities which are not significantly different as a homogeneous set. Such groupings reduce the complexity of the rankings without losing information. We pursue this classification using both statistical significance and effect sizes of differences among 902 univer...
Article
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Recently, Hirsch (2019a) proposed a new variant of the h index called the h α index. The h α index was criticized by Leydesdorff, Bornmann, and Opthof (2019). One of their most important points is that the index reinforces the Matthew effect in science. The Matthew effect was defined by Merton (1968) as follows: “the Matthew effect consists in the...
Article
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We replicate and analyze the topic model which was commissioned to King’s College and Digital Science for the Research Evaluation Framework (REF 2014) in the United Kingdom: 6,638 case descriptions of societal impact were submitted by 154 higher-education institutes. We compare the Latent Dirichlet Allocation (LDA) model with Principal Component An...
Preprint
Full-text available
Abstract Problem-solving often requires crossing boundaries, such as those between disciplines. In collaborations with third parties, however, “interdisciplinarity” is not an objective in itself, but a means for creating “synergy.” Synergy means that the whole offers more possibilities than the sum of its parts. We discuss recent advances in the o...
Preprint
Full-text available
Recently, Hirsch (2019a) proposed a new variant of the h index called the $h_\alpha$ index. He formulated as follows: "we define the $h_\alpha$ index of a scientist as the number of papers in the h-core of the scientist (i.e. the set of papers that contribute to the h-index of the scientist) where this scientist is the $\alpha$-author" (p. 673). Th...
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Purpose: This paper aims to extend the existing views of coopetition into the broader context of open coopetition. Design/methodology/approach: The authors build on the literature about open innovation cooperation between competitors in the open-source software industry, which we generalize to show that open coopetition between competitors and thir...
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Twitter accounts have already been used in many scientometric studies, but the meaningfulness of the data for societal impact measurements in research evaluation has been questioned. Earlier research focused on social media counts and neglected the interactive nature of the data. We explore a new network approach based on Twitter data in which we c...
Article
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We propose the I3* indicator as a non-parametric alternative to the journal impact factor (JIF) and h-index. We apply I3* to more than 10,000 journals. The results can be compared with other journal metrics. I3* is a promising variant within the general scheme of non-parametric I3 indicators introduced previously: I3* provides a single metric which...
Preprint
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In his reaction to our recent article about diversity measurement in Journal of Informetrics (Leydesdorff et al., 2019), Rousseau (2019) considers DIV as an acceptable diversity measure that needs further refinement. DIV improves on Rao-Stirling diversity Δ (Rao, 1982; Stirling, 2007) or its modified version 2D3 (Zhang et al., 2016) because DIV mee...
Article
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Recently, the integrated impact indicator (I3) was introduced where citations are weighted in accordance with the percentile rank class of each publication in a set of publications. I3 can also be used as a field-normalized indicator. Field-normalization is common practice in bibliometrics, especially when institutions and countries are compared. P...