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1.
Biosystems ; 198: 104236, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32898644

RESUMO

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 selection" is based on genotypes that are observable (like DNA), cultural selection mechanisms are not hard-wired, but evolve. The "genotypes" of cultural evolution are codes in the communication which can operate as selections upon one another. Local instantiations shape trajectories; regimes operate as selection pressure with reference to the next-order horizons of meaning. These orders of expectations can operate incursively and hyper-incursively against the arrow of time and thus generate redundancies: (i) horizons of meaning can be expected to overlap and (ii) distinctions generate new options enlarging the maximum capacities. Information theory and the theory of anticipatory systems can be used for the elaboration of operations against the arrow of time. New options can be a synergetic effect of interactions among codes in the communication and serve as sources of wealth in a knowledge-based economy.


Assuntos
Algoritmos , Comunicação , Evolução Cultural , Modelos Teóricos , Teoria Psicológica , Autoimagem , Humanos , Metacognição/fisiologia , Psicologia do Self
2.
J Assoc Inf Sci Technol ; 70(2): 198-201, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32728598

RESUMO

A recent publication in Nature reports that public R&D funding is only weakly correlated with the citation impact of a nation's articles as measured by the field-weighted citation index (FWCI; defined by Scopus). On the basis of the supplementary data, we up-scaled the design using Web of Science data for the decade 2003-2013 and OECD funding data for the corresponding decade assuming a 2-year delay (2001-2011). Using negative binomial regression analysis, we found very small coefficients, but the effects of international collaboration are positive and statistically significant, whereas the effects of government funding are negative, an order of magnitude smaller, and statistically nonsignificant (in two of three analyses). In other words, international collaboration improves the impact of research articles, whereas more government funding tends to have a small adverse effect when comparing OECD countries.

3.
Scientometrics ; 116(3): 2113-2121, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30147205

RESUMO

The dilemma which remained unsolved using Rao-Stirling diversity, namely of how variety and balance can be combined into "dual concept diversity" (Stirling in SPRU electronic working paper series no. 28. http://www.sussex.ac.uk/Units/spru/publications/imprint/sewps/sewp28/sewp28.pdf, 1998, p. 48f.) can be clarified by using Nijssen et al.'s (Coenoses 13(1):33-38 1998) argument that the Gini coefficient is a perfect indicator of balance. However, the Gini coefficient is not an indicator of variety; this latter term can be operationalized independently as relative variety. The three components of diversity-variety, balance, and disparity-can thus be clearly distinguished and independently operationalized as measures varying between zero and one. The new diversity indicator ranges with more resolving power in the empirical case.

4.
Scientometrics ; 115(2): 1119-1123, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29628536

RESUMO

Teixeira da Silva and Dobránszki (Scientometrics. 10.1007/s11192-018-2680-3, 2018) describe practical problems in using the h-index for the purpose of research evaluation. For example, they discuss the h-index differences among the bibliometric databases. In this Letter to the Editor, we argue for abstaining from using the h-index. One can use normalized indicators instead.

5.
PLoS One ; 13(3): e0194805, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29579088

RESUMO

This study asks the question on which national "shoulders" the world's top-level research stands. Traditionally, the number of citations to national papers has been the evaluative measures of national scientific standings. We raise a different question: instead of analyzing the citations to a countries' articles (the forward view), we examine references to prior publications from specific countries cited in the most elite publications (the backward-citing-view). "Elite publications" are operationalized as the top-1% most-highly cited articles. Using the articles published from 2004 to 2013, we examine the research referenced in these works. Our results confirm the well-known fact that China has emerged to become a major player in science. However, China still belongs to the low contributors when countries are ranked as contributors to the cited references in top-1% articles. Using this perspective, the results do not support a decreasing trend for the USA; in fact, the USA exceeds expectations (compared to its publication share) in terms of references in the top-1% articles. Switzerland, Sweden, and the Netherlands also appear at the top of the list. However, the results for Germany are lower than statistically expected.


Assuntos
Publicações , Bibliometria , Fator de Impacto de Revistas
6.
Scientometrics ; 114(2): 439-448, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29449749

RESUMO

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://www.crexplorer.net) was specifically developed for RPYS. In this study, we use this program to investigate the historical roots of Eugene Garfield's oeuvre.

7.
Scientometrics ; 114(2): 567-592, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29449751

RESUMO

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 (BC) and diversity, we elaborate on the question of how to distinguish and rank journals in terms of interdisciplinarity. Interdisciplinarity, however, is difficult to operationalize in the absence of an operational definition of disciplines; the diversity of a unit of analysis is sample-dependent. BC can be considered as a measure of multi-disciplinarity. Diversity of co-citation in a citing document has been considered as an indicator of knowledge integration, but an author can also generate trans-disciplinary-that is, non-disciplined-variation by citing sources from other disciplines. Diversity in the bibliographic coupling among citing documents can analogously be considered as diffusion  or differentiation of knowledge across disciplines. Because the citation networks in the cited direction reflect both structure and variation, diversity in this direction is perhaps the best available measure of interdisciplinarity at the journal level. Furthermore, diversity is based on a summation and can therefore be decomposed; differences among (sub)sets can be tested for statistical significance. In the appendix, a general-purpose routine for measuring diversity in networks is provided.

9.
Scientometrics ; 112(3): 1573-1591, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28804179

RESUMO

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 rethinking various parameter choices. The new maps are significantly different from the previous ones, although this may not always be obvious on visual inspection. We provide nested maps online and a routine for generating portfolio overlays on the maps; a new tool is provided for "difference maps" between patent portfolios of organizations or firms. This is illustrated by comparing the portfolios of patents granted to two competing firms-Novartis and MSD-in 2016. Furthermore, the data is organized for the purpose of statistical analysis.

10.
Scientometrics ; 110(3): 1601-1614, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28255188

RESUMO

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. In this short communication, we provide background on the journal mapping/clustering and an explanation about and instructions for the routine. We compare journal maps for 2015 with those for 2014 and show the delineations among fields and subfields to be sensitive to fluctuations. Labels for fields and sub-fields are not provided by the routine, but an analyst can add them for pragmatic or intellectual reasons. The routine provides a means of testing one's assumptions against a baseline without claiming authority; clusters of related journals can be visualized to understand communities. The routine is generic and can be used for any 1-mode network.

11.
Soc Sci Inf (Paris) ; 56(1): 4-27, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28232771

RESUMO

Following a suggestion from Warren Weaver, we extend the Shannon model of communication piecemeal into a complex systems model in which communication is differentiated both vertically and horizontally. This model enables us to bridge the divide between Niklas Luhmann's theory of the self-organization of meaning in communications and empirical research using information theory. First, we distinguish between communication relations and correlations among patterns of relations. The correlations span a vector space in which relations are positioned and can be provided with meaning. Second, positions provide reflexive perspectives. Whereas the different meanings are integrated locally, each instantiation opens global perspectives - 'horizons of meaning' - along eigenvectors of the communication matrix. These next-order codifications of meaning can be expected to generate redundancies when interacting in instantiations. Increases in redundancy indicate new options and can be measured as local reduction of prevailing uncertainty (in bits). The systemic generation of new options can be considered as a hallmark of the knowledge-based economy.


Suivant une suggestion de Warren Weaver, nous étendons le modèle de communication au coup par coup de Shannon à un modèle de systèmes complexes où la communication est différenciée à la fois verticalement et horizontalement. Ce modèle nous permet de combler le fossé entre la théorie de l'auto-organisation du sens dans les communications de Luhmann et la recherche empirique qui utilise la théorie de l'information. Tout d'abord, nous établissons une distinction entre relations de communication et corrélations entre distributions de relations. Les corrélations couvrent un espace vectoriel où les relations sont positionnées et où l'on peut leur attribuer un sens. Deuxièmement, les positions offrent des perspectives réflexives. Alors que les différents sens sont intégrés localement, chaque instanciation ouvre des perspectives globales ­ des horizons de sens ­ le long des vecteurs propres de la matrice de communication. On peut s'attendre à ce que ces codifications de sens voisines puissent générer des redondances mutuelles lorsqu'elles interagissent en instanciations. L'augmentation des redondances indique de nouvelles options et peut être mesurée comme une réduction locale de la prévalence de l'incertitude (en bits). La génération systémique de nouvelles options peut être considérée comme la marque de fabrique de l'économie de la connaissance.

12.
Scientometrics ; 109(3): 2077-2091, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27942085

RESUMO

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 documents; using PubMed/MEDLINE data, a matrix of the citing documents versus MeSH terms can be generated analogously. The two matrices can also be reorganized into a 2-mode matrix of MeSH terms versus cited references. Using the abbreviated journal names in the references, one can, for example, address the question whether MeSH terms can be used as an alternative to WoS Subject Categories for the purpose of normalizing citation data. We explore the applicability of the routines in the case of a research program about the amyloid cascade hypothesis in Alzheimer's disease. One conclusion is that referenced journals provide archival structures, whereas MeSH terms indicate mainly variation (including novelty) at the research front. Furthermore, we explore the option of using the citing/cited matrix for main-path analysis as a by-product of the software.

13.
Scientometrics ; 109(3): 2129-2150, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27942086

RESUMO

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 data and indicators; (2) bibliometricians who develop and test indicators; (3) research managers who apply the indicators; and (4) the scientists being evaluated with potentially competing career interests. These different positions may lead to different and sometimes conflicting perspectives on the meaning and value of the indicators. The indicators can thus be considered as boundary objects which are socially constructed in translations among these perspectives. This paper proposes an analytical clarification by listing an informed set of (sometimes unsolved) problems in bibliometrics which can also shed light on the tension between simple but invalid indicators that are widely used (e.g., the h-index) and more sophisticated indicators that are not used or cannot be used in evaluation practices because they are not transparent for users, cannot be calculated, or are difficult to interpret.

14.
PLoS One ; 11(11): e0165277, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27832084

RESUMO

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 foreign industrial partners, however, more variation exists among Chinese universities than among US universities. The US system is domestically oriented more than that of China. In the USA, the intensity of university-industry collaboration is determined by research quality, whereas in China this is not the case. In both China and the USA, distance is not critical for the establishment of domestic university-industry collaboration. A high correlation is found between productivity indicators including total publications and university-industry co-authored publications. However, the productivity indicators are less correlated with the intensity of university-industry collaboration. Large research universities with strong ties to domestic industry play critical roles in both national publication systems.


Assuntos
Comportamento Cooperativo , Indústrias , Universidades , Bibliometria , China , Disciplinas das Ciências Naturais , Editoração , Análise de Regressão , Pesquisa , Estados Unidos
15.
Scientometrics ; 105(3): 1441-1451, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26594072

RESUMO

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 exclusively due to increases and decreases in the variety of the classifications, and not to disparity or technological distance, measured as (1 - cosine). A single frequency component can accordingly be shown in the periodogram. Furthermore, the cyclical patterns are associated with the numbers of inventors in the respective technologies. Sometimes increased variety leads to a boost in the number of inventors, but in early phases-when the technology is still under construction-it can also be the other way round. Since the development of the cycles thus seems independent of technological distances among the patents, the visualization in terms of patent maps, can be considered as addressing an analytically different set of research questions.

16.
Scientometrics ; 105(3): 2197-2214, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26594074

RESUMO

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 specified in scholarly literature; and (3) intellectually the sciences (disciplines, specialties) tend to self-organize as systems of rationalized expectations. Whereas social organizations remain localized, academic writings can circulate, and expectations can be stabilized and globalized using symbolically generalized codes of communication. The intellectual restructuring, however, remains latent as a second-order dynamics that can be accessed by participants only reflexively. Yet, the emerging "horizons of meaning" provide feedback to the historically developing organizations by constraining the possible future states as boundary conditions. I propose to model these possible future states using incursive and hyper-incursive equations from the computation of anticipatory systems. Simulations of these equations enable us to visualize the couplings among the historical-i.e., recursive-progression of social structures along trajectories, the evolutionary-i.e., hyper-incursive-development of systems of expectations at the regime level, and the incursive instantiations of expectations in actions, organizations, and texts.

17.
PLoS One ; 10(7): e0131816, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26196296

RESUMO

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, have increased their participation in global science, in part by doubling their spending on R&D; they are increasingly likely to appear as partners on internationally coauthored scientific papers. Given the growth of connections at the international level, it is helpful to examine the phenomenon as a communications network and to consider the network as a new organization on the world stage that adds to and complements national systems. When examined as interconnections across the globe over two decades, a global network has grown denser but not more clustered, meaning there are many more connections but they are not grouping into exclusive 'cliques'. This suggests that power relationships are not reproducing those of the political system. The network has features an open system, attracting productive scientists to participate in international projects. National governments could gain efficiencies and influence by developing policies and strategies designed to maximize network benefits-a model different from those designed for national systems.


Assuntos
Redes Comunitárias , Países em Desenvolvimento , Cooperação Internacional , Pesquisa , Humanos
18.
EMBO Rep ; 16(3): 262, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25604131

Assuntos
Bibliometria , Pesquisa
19.
Scientometrics ; 102: 1101-1117, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25632165

RESUMO

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? Trying to answer these questions, this study aims to shed light on international collaboration by researchers from the Eastern European countries (Russia, Ukraine, Belarus, Moldova, Bulgaria, the Czech Republic, Hungary, Poland, Romania, and Slovakia). The number of publications and normalized citation impact values are compared for these countries based on InCites (Thomson Reuters), from 1981 up to 2011. The international collaboration by researchers affiliated to institutions in Eastern European countries at the time points of 1990, 2000 and 2011 was studied with the help of Pajek and VOSviewer software, based on data from the Science Citation Index (Thomson Reuters). Our results show that the breakdown of the communist regime did not lead, on average, to a huge improvement in the publication performance of the Eastern European countries and that the increase in international co-authorship relations by the researchers affiliated to institutions in these countries was smaller than expected. Most of the Eastern European countries are still subject to changes and are still awaiting their boost in scientific development.

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