arXiv subjects

Loet Leydesdorff

Publications and source records attributed to Loet Leydesdorff.

At least 289 records · Page 16Linked to original sources

arXiv2009

Korean journals in the Science Citation Index: What do they reveal about the intellectual structure of S&T in Korea?

During the last decade, we have witnessed a sustained growth of South Korea's research output in terms of the world share of publications in the Science Citation Index database. However, Korea's citation performance is not yet as competitive as publication performance. In this study, the authors examine the intellectual structure of Korean S&T field based on social network analysis of journal-journal citation data using the ten Korean SCI journals as seed journals. The results reveal that Korean SCI journals function more like publication places, neither research channels nor information sources among national scientists. Thus, these journals may provide Korean scholars with access to international scientific communities by facilitating the respective entry barriers. However, there are no citation relations based on their Korean background. Furthermore, we intend to draw some policy implications which may be helpful to increase Korea's research potential.

physics.soc-ph↗

arXiv2009

Retrieval of very large numbers of items in the Web of Science: an exercise to develop accurate search strategies

The current communication presents a simple exercise with the aim of solving a singular problem: the retrieval of extremely large amounts of items in the Web of Science interface. As it is known, Web of Science interface allows a user to obtain at most 100,000 items from a single query. But what about queries that achieve a result of more than 100,000 items? The exercise developed one possible way to achieve this objective. The case study is the retrieval of the entire scientific production from the United States in a specific year. Different sections of items were retrieved using the field Source of the database. Then, a simple Boolean statement was created with the aim of eliminating overlapping and to improve the accuracy of the search strategy. The importance of team work in the development of advanced search strategies was noted.

cs.DL↗

arXiv2009

Past performance, peer review, and project selection: A case study in the social and behavioral sciences

Does past performance influence success in grant applications? In this study we test whether the grant allocation decisions of the Netherlands Research Council for the Economic and Social Sciences correlate with the past performances of the applicants in terms of publications and citations, and with the results of the peer review process organized by the Council. We show that the Council is successful in distinguishing grant applicants with above-average performance from those with below-average performance, but within the former group no correlation could be found between past performance and receiving a grant. When comparing the best performing researchers who were denied funding with the group of researchers who received it, the rejected researchers significantly outperformed the funded ones. Furthermore, the best rejected proposals score on average as high on the outcomes of the peer review process as the accepted proposals. Finally, we found that the Council under study successfully corrected for gender effects during the selection process. We explain why these findings may be more general than for this case only. However, if research councils are not able to select the 'best' researchers, perhaps they should reconsider their mission. In a final section with policy implications, we discuss the role of research councils at the level of the science system in terms of variation, innovation, and quality control.

physics.soc-ph↗

arXiv2009

The Dynamics of Exchanges and References among Scientific Texts, and the Autopoiesis of Discursive Knowledge

Discursive knowledge emerges as codification in flows of communication. The flows of communication are constrained and enabled by networks of communications as their historical manifestations at each moment of time. New publications modify the existing networks by changing the distributions of attributes and relations in document sets, while the networks are self-referentially updated along trajectories. Codification operates reflexively: the network structures are reconstructed from the perspective of hindsight. Codification along different axes differentiates discursive knowledge into specialties. These intellectual control structures are constructed bottom-up, but feed top-down back upon the production of new knowledge. However, the forward dynamics of diffusion in the development of the communication networks along trajectories differs from the feedback mechanisms of control. Analysis of the development of scientific communication in terms of evolving scientific literatures provides us with a model which makes these evolutionary processes amenable to measurement.

cs.CY↗

arXiv2009

Lock-in & Break-out from Technological Trajectories: Modeling and policy implications

Arthur [1,2] provided a model to explain the circumstances that lead to technological lock-in into a specific trajectory. We contribute substantially to this area of research by investigating the circumstances under which technological development may break-out of a trajectory. We argue that for this to happen, a third selection mechanism--beyond those of the market and of technology--needs to upset the lock-in. We model the interaction, or mutual shaping among three selection mechanisms, and thus this paper also allows for a better understanding of when a technology will lock-in into a trajectory, when a technology may break-out of a lock-in, and when competing technologies may co-exist in a balance. As a system is conceptualized to gain a (third) degree of freedom, the possibility of bifurcation is introduced into the model. The equations, in which interactions between competition and selection mechanisms can be modeled, allow one to specify conditions for lock-in, competitive balance, and break-out.

physics.soc-ph↗

arXiv2009

Knowledge linkage structures in communication studies using citation analysis among communication journals

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.

cs.DL↗

arXiv2009

The relation between Pearson's correlation coefficient r and Salton's cosine measure

The relation between Pearson's correlation coefficient and Salton's cosine measure is revealed based on the different possible values of the division of the L1-norm and the L2-norm of a vector. These different values yield a sheaf of increasingly straight lines which form together a cloud of points, being the investigated relation. The theoretical results are tested against the author co-citation relations among 24 informetricians for whom two matrices can be constructed, based on co-citations: the asymmetric occurrence matrix and the symmetric co-citation matrix. Both examples completely confirm the theoretical results. The results enable us to specify an algorithm which provides a threshold value for the cosine above which none of the corresponding Pearson correlations would be negative. Using this threshold value can be expected to optimize the visualization of the vector space.

cs.IR↗

arXiv2009

The Non-linear Dynamics of Meaning-Processing in Social Systems

Social order cannot be considered as a stable phenomenon because it contains an order of reproduced expectations. When the expectations operate upon one another, they generate a non-linear dynamics that processes meaning. Specific meaning can be stabilized, for example, in social institutions, but all meaning arises from a horizon of possible meanings. Using Luhmann's (1984) social systems theory and Rosen's (1985) theory of anticipatory systems, I submit equations for modeling the processing of meaning in inter-human communication. First, a self-referential system can use a model of itself for the anticipation. Under the condition of functional differentiation, the social system can be expected to entertain a set of models; each model can also contain a model of the other models. Two anticipatory mechanisms are then possible: one transversal between the models, and a longitudinal one providing the modeled systems with meaning from the perspective of hindsight. A system containing two anticipatory mechanisms can become hyper-incursive. Without making decisions, however, a hyper-incursive system would be overloaded with uncertainty. Under this pressure, informed decisions tend to replace the "natural preferences" of agents and an order of cultural expectations can increasingly be shaped.

physics.soc-ph↗

arXiv2009

Luhmann Reconsidered: Steps Towards an Empirical Research Programme in the Sociology of Communication?

Although Luhmann formulated with modesty and precaution, for example in Die Wissenschaft der Gesellschaft (1990a, at pp. 412f.), that his theory claims to be a universal one because it is self-referential, the "operational closure" that follows from this assumption easily generates a problem for empirical research. Can a theory which considers society--and science as one of its subsystems--operationally closed, nevertheless contribute to the project of Enlightenment which Popper (1945) so vigorously identified as the driver of an open society? How can a theory which proclaims itself to be circular and universal nevertheless claim to celebrate "the triumph of the Enlightenment" Luhmann, (1990a, at p. 548)? Is the lack of an empirical program of research building on Luhmann's theory fortuitous or does it indicate that this theory should be considered as a philosophy rather than a heuristic for the explanation of operations in social systems?

physics.soc-ph↗

arXiv2009

Is the United States losing ground in science? A global perspective on the world science system

Based on the Science Citation IndexExpanded webversion, the USA is still by far the strongest nation in terms of scientific performance. Its relative decline in percentage share of publications is largely due to the emergence of China and other Asian nations. In 2006, China has become the second largest nation in terms of the number of publications within this database. In terms of citations, the competitive advantage of the American domestic market is diminished, while the European Union EU is profiting more from the enlargement of the database over time than the US. However, the USA is still outperforming all other countries in terms of highly cited papers and citationpublication ratios, and it is more successful than the EU in coordinating its research efforts in strategic priority areas like nanotechnology. In this field, the Peoples Republic of China PRC has become second largest nation in both numbers of papers published and citations behind the USA.

physics.soc-ph↗

arXiv2009

Macro-level Indicators of the Relations between Research Funding and Research Output

In response to the call for a science of science policy, we discuss the contribution of indicators at the macro-level of nations from a scientometric perspective. In addition to global trends such as the rise of China, one can relate percentages of world share of publications to government expenditure in academic research. The marginal costs of improving one's share are increasing over time. Countries differ considerably in terms of the efficiency of turning (financial) input into bibliometrically measurable output. Both funding schemes and disciplinary portfolios differ among countries. A price per paper can nevertheless be estimated. The percentages of GDP spent on academic research in different nations are significantly correlated to historical contingencies such as the percentage of researchers in the population. The institutional dynamics make strategic objectives such as the Lisbon objective of the EU--that is, spending 3% of GDP for R&D in 2010--unrealistic.

physics.soc-ph↗

arXiv2009

The communication of meaning in social systems

The sociological domain is different from the psychological one insofar as meaning can be communicated at the supra-individual level (Schutz, 1932; Luhmann, 1984). The computation of anticipatory systems enables us to distinguish between these domains in terms of weakly and strongly anticipatory systems with a structural coupling between them (Maturana, 1978). Anticipatory systems have been defined as systems which entertain models of themselves (Rosen, 1985). The model provides meaning to the modeled system from the perspective of hindsight, that is, by advancing along the time axis towards possible future states. Strongly anticipatory systems construct their own future states (Dubois, 1998a and b). The dynamics of weak and strong anticipations can be simulated as incursion and hyper-incursion, respectively. Hyper-incursion generates "horizons of meaning" (Husserl, 1929) among which choices have to be made by incursive agency.

physics.soc-ph↗

arXiv2009

The Delineation of an Interdisciplinary Specialty in terms of a Journal Set: The Case of Communication Studies

A journal set in an interdisciplinary or newly developing area can be determined by including the journals classified under the most relevant ISI Subject Categories into a journal-journal citation matrix. Despite the fuzzy character of borders, factor analysis of the citation patterns enables us to delineate the specific set by discarding the noise. This methodology is illustrated using communication studies as a hybrid development between political science and social psychology. The development can be visualized using animations which support the claim that a specific journal set in communication studies is increasingly developing, notably in the "being cited" patterns. The resulting set of 28 journals in communication studies is smaller and more focused than the 45 journals classified by the ISI Subject Categories as "Communication". The proposed method is tested for its robustness by extending the relevant environments to sets including many more journals.

physics.soc-ph↗

arXiv2009

National and International Dimensions of the Triple Helix in Japan: University-Industry-Government versus International Co-Authorship Relations

International co-authorship relations and university-industry-government ("Triple Helix") relations have hitherto been studied separately. Using Japanese (ISI) publication data for the period 1981-2004, we were able to study both kinds of relations in a single design. In the Japanese file, 1,277,823 articles with at least one Japanese address were attributed to the three sectors, and we know additionally whether these papers were co-authored internationally. Using the mutual information in three and four dimensions, respectively, we show that the Japanese Triple-Helix system has continuously been eroded at the national level. However, since the middle of the 1990s, international co-authorship relations have contributed to a reduction of the uncertainty. In other words, the national publication system of Japan has developed a capacity to retain surplus value generated internationally. In a final section, we compare these results with an analysis based on similar data for Canada. A relative uncoupling of local university-industry relations because of international collaborations is indicated in both national systems.

physics.soc-ph↗

arXiv2009

A Global Map of Science Based on the ISI Subject Categories

The ISI subject categories classify journals included in the Science Citation Index (SCI). The aggregated journal-journal citation matrix contained in the Journal Citation Reports can be aggregated on the basis of these categories. This leads to an asymmetrical transaction matrix (citing versus cited) which is much more densely populated than the underlying matrix at the journal level. Exploratory factor analysis leads us to opt for a fourteen-factor solution. This solution can easily be interpreted as the disciplinary structure of science. The nested maps of science (corresponding to 14 factors, 172 categories, and 6,164 journals) are brought online at http://www.leydesdorff.net/map06/index.htm. An analysis of interdisciplinary relations is pursued at three levels of aggregation using the newly added ISI subject category of "Nanoscience & nanotechnology". The journal level provides the finer grained perspective. Errors in the attribution of journals to the ISI subject categories are averaged out so that the factor analysis can reveal the main structures. The mapping of science can, therefore, be comprehensive at the level of ISI subject categories.

physics.soc-ph↗

arXiv2009

How are new citation-based journal indicators adding to the bibliometric toolbox?

The launching of Scopus and Google Scholar, and methodological developments in Social Network Analysis have made many more indicators for evaluating journals available than the traditional Impact Factor, Cited Half-life, and Immediacy Index of the ISI. In this study, these new indicators are compared with one another and with the older ones. Do the various indicators measure new dimensions of the citation networks, or are they highly correlated among them? Are they robust and relatively stable over time? Two main dimensions are distinguished -- size and impact -- which together shape influence. The H-index combines the two dimensions and can also be considered as an indicator of reach (like Indegree). PageRank is mainly an indicator of size, but has important interactions with centrality measures. The Scimago Journal Ranking (SJR) indicator provides an alternative to the Journal Impact Factor, but the computation is less easy.

physics.soc-ph↗

arXiv2009

Journal Maps on the Basis of Scopus Data: A comparison with the Journal Citation Reports of the ISI

Using the Scopus dataset (1996-2007) a grand matrix of aggregated journal-journal citations was constructed. This matrix can be compared in terms of the network structures with the matrix contained in the Journal Citation Reports (JCR) of the Institute of Scientific Information (ISI). Since the Scopus database contains a larger number of journals and covers also the humanities, one would expect richer maps. However, the matrix is in this case sparser than in the case of the ISI data. This is due to (i) the larger number of journals covered by Scopus and (ii) the historical record of citations older than ten years contained in the ISI database. When the data is highly structured, as in the case of large journals, the maps are comparable, although one may have to vary a threshold (because of the differences in densities). In the case of interdisciplinary journals and journals in the social sciences and humanities, the new database does not add a lot to what is possible with the ISI databases.

physics.soc-ph↗

arXiv2008

Content-based and Algorithmic Classifications of Journals: Perspectives on the Dynamics of Scientific Communication and Indexer Effects

The aggregated journal-journal citation matrix -based on the Journal Citation Reports (JCR) of the Science Citation Index- can be decomposed by indexers and/or algorithmically. In this study, we test the results of two recently available algorithms for the decomposition of large matrices against two content-based classifications of journals: the ISI Subject Categories and the field/subfield classification of Glaenzel & Schubert (2003). The content-based schemes allow for the attribution of more than a single category to a journal, whereas the algorithms maximize the ratio of within-category citations over between-category citations in the aggregated category-category citation matrix. By adding categories, indexers generate between-category citations, which may enrich the database, for example, in the case of inter-disciplinary developments. The consequent indexer effects are significant in sparse areas of the matrix more than in denser ones. Algorithmic decompositions, on the other hand, are more heavily skewed towards a relatively small number of categories, while this is deliberately counter-acted upon in the case of content-based classifications. Because of the indexer effects, science policy studies and the sociology of science should be careful when using content-based classifications, which are made for bibliographic disclosure, and not for the purpose of analyzing latent structures in scientific communications. Despite the large differences among them, the four classification schemes enable us to generate surprisingly similar maps of science at the global level. Erroneous classifications are cancelled as noise at the aggregate level, but may disturb the evaluation locally.

physics.data-an↗