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Showing papers in "Scientometrics in 2007"


Journal ArticleDOI
TL;DR: The effectiveness and the benefits of the new indices are exhibited to unfold the full potential of the h-index, with extensive experimental results obtained from the DBLP, a widely known on-line digital library.
Abstract: What is the value of a scientist and its impact upon the scientific thinking? How can we measure the prestige of a journal or a conference? The evaluation of the scientific work of a scientist and the estimation of the quality of a journal or conference has long attracted significant interest, due to the benefits by obtaining an unbiased and fair criterion. Although it appears to be simple, defining a quality metric is not an easy task. To overcome the disadvantages of the present metrics used for ranking scientists and journals, J. E. Hirsch proposed a pioneering metric, the now famous h-index. In this article we demonstrate several inefficiencies of this index and develop a pair of generalizations and effective variants of it to deal with scientist ranking and publication forum ranking. The new citation indices are able to disclose trendsetters in scientific research, as well as researchers that constantly shape their field with their influential work, no matter how old they are. We exhibit the effectiveness and the benefits of the new indices to unfold the full potential of the h-index, with extensive experimental results obtained from the DBLP, a widely known on-line digital library.

399 citations


Journal ArticleDOI
TL;DR: Two metrics that together help gauge how interdisciplinary a body of research is are offered, which draw upon Web of Knowledge Subject Categories (SCs) as key units of analysis.
Abstract: We offer two metrics that together help gauge how interdisciplinary a body of research is. Both draw upon Web of Knowledge Subject Categories (SCs) as key units of analysis. We have assembled two substantial Web of Knowledge samples from which to determine how closely individual SCs relate to each other. “Integration” measures the extent to which a research article cites diverse SCs. “Specialization” considers the spread of SCs in which the body of research (e.g., the work of a given author in a specified time period) is published. Pilot results for a sample of researchers show a surprising degree of interdisciplinarity.

351 citations


Journal ArticleDOI
TL;DR: The tsunami publication patterns in the first 8 months after the Indonesia tsunami occurred on 26 December 2004 indicated a high percentage of non-article publications and more documents being published in journals with higher impact factors.
Abstract: The use of the bibilometric analytical technique for examining tsunami research does not exist in the literature. The objective of the study was to perform a bibliometric analysis of all tsunami-related publications in the Science Citation Index (SCI). Analyzed parameters included document type, language of publication, publication output, authorship, publication patterns, distribution of subject category, distribution of author keywords, country of publication, most-frequently cited article, and document distribution after the Indonesia tsunami. The US and Japan produced 53% of the total output where the seven major industrial countries accounted for the majority of the total production. English was the dominant language, comprising 95% of articles. A simulation model was applied to describe the relationship between the number of authors and the number of articles, the number of journals and the number of articles, and the percentage of total articles and the number of times a certain keyword was used. Moreover the tsunami publication patterns in the first 8 months after the Indonesia tsunami occurred on 26 December 2004 indicated a high percentage of non-article publications and more documents being published in journals with higher impact factors.

348 citations


Journal ArticleDOI
TL;DR: A profile of Scopus is drawn in terms of its coverage by areas — geographic and thematic — and the significance of peer-review in its publications and the design of policies for the use of scientific databases in scientific promotion.
Abstract: Our aim is to compare the coverage of the Scopus database with that of Ulrich, to determine just how homogenous it is in the academic world. The variables taken into account were subject distribution, geographical distribution, distribution by publishers and the language of publication. The analysis of the coverage of a product of this nature should be done in relation to an accepted model, the optimal choice being Ulrich’s Directory, considered the international point of reference for the most comprehensive information on journals published throughout the world. The results described here allow us to draw a profile of Scopus in terms of its coverage by areas — geographic and thematic — and the significance of peer-review in its publications. Both these aspects are highly pragmatic considerations for information retrieval, the evaluation of research, and the design of policies for the use of scientific databases in scientific promotion.

309 citations


Journal ArticleDOI
TL;DR: A simple way to put in a common scale the h values of researchers working in different scientific ISI fields is proposed, so that the foreseeable misuse of this index for inter-areas comparison might be prevented, or at least alleviated.
Abstract: We propose a simple way to put in a common scale the h values of researchers working in different scientific ISI fields, so that the foreseeable misuse of this index for inter-areas comparison might be prevented, or at least, alleviated.

236 citations


Journal ArticleDOI
TL;DR: The incentives that underlie self-citation are examined by studying how authors’ references to their own works affect the citations they receive from others, and it is shown that the more one cites oneself the moreOne is cited by other scholars.
Abstract: Self-citations — those where authors cite their own works — account for a significant portion of all citations. These self-references may result from the cumulative nature of individual research, the need for personal gratification, or the value of self-citation as a rhetorical and tactical tool in the struggle for visibility and scientific authority. In this article we examine the incentives that underlie self-citation by studying how authors’ references to their own works affect the citations they receive from others. We report the results of a macro study of more than half a million citations to articles by Norwegian scientists that appeared in the Science Citation Index. We show that the more one cites oneself the more one is cited by other scholars. Controlling for numerous sources of variation in cumulative citations from others, our models suggest that each additional self-citation increases the number of citations from others by about one after one year, and by about three after five years. Moreover, there is no significant penalty for the most frequent self-citers — the effect of self-citation remains positive even for very high rates of self-citation. These results carry important policy implications for the use of citations to evaluate performance and distribute resources in science and they represent new information on the role and impact of self-citations in scientific communication.

236 citations


Journal ArticleDOI
TL;DR: Results show that, although some indicators differ considerably across selected rankings and even many indicators are unique, indicators referred to research and scientific productivity from university academic staff have a prominent role across all approaches.
Abstract: International academic rankings that compare world universities have proliferated recently. In accordance with latter conceptual and methodological advances in academic rankings approaches, five selection criteria are defined and four international university rankings are selected. A comparative analysis of the four rankings is presented taking into account both the indicators frequency and its weights. Results show that, although some indicators differ considerably across selected rankings and even many indicators are unique, indicators referred to research and scientific productivity from university academic staff have a prominent role across all approaches. The implications of obtained data for main rankings consumers are discussed.

200 citations


Journal ArticleDOI
TL;DR: Findings show that respondents get involved in patenting activities to enhance their prestige and reputation, and look for new stimuli for their research; personal earnings do not represent a main incentive.
Abstract: This paper reports results from a survey of 208 Italian faculty members, inventors of university-owned patents, on their motivation to get involved in university patenting activities, the obstacles that they faced, and their suggestions to foster the commercialization of academic knowledge through patents. Findings show that respondents get involved in patenting activities to enhance their prestige and reputation, and look for new stimuli for their research; personal earnings do not represent a main incentive. University-level patent regulations reduce the obstacles perceived by inventors, as far as they signal universities’ commitment to legitimate patenting activities. Implications for innovation policies are discussed.

191 citations


Journal ArticleDOI
TL;DR: Examination of general characteristics of African science from a quantitative ‘scientometric’ perspective shows that while Africa’s share in worldwide science has steadily declined, the share of international co-publications has increased very significantly, whereas low levels of international citation impact persist.
Abstract: This paper examines general characteristics of African science from a quantitative ‘scientometric’ perspective. More specifically, that of research outputs of Africa-based authors published in the scientific literature during the years 1980–2004, either within the international journals representing ‘mainstream’ science, or within national and regional journals reflecting ‘indigenous science’. As for the international journals, the findings derived from Thomson Scientific’s Citation Indexes show that while Africa’s share in worldwide science has steadily declined, the share of international co-publications has increased very significantly, whereas low levels of international citation impact persist. A case study of South African journals reveals the existence of several journals that are not processed for these international databases but nonetheless show a distinctive citation impact on international research communities.

187 citations


Journal ArticleDOI
TL;DR: An analysis of 2, 765 articles published in four math journals from 1997 to 2005 indicates that articles deposited in the arXiv received 35% more citations on average than non-deposited articles, and that this difference was most pronounced for highly-cited articles.
Abstract: An analysis of 2, 765 articles published in four math journals from 1997 to 2005 indicate that articles deposited in the arXiv received 35% more citations on average than non-deposited articles (an advantage of about 1.1 citations per article), and that this difference was most pronounced for highly-cited articles. Open Access, Early View, and Quality Differential were examined as three non-exclusive postulates for explaining the citation advantage. There was little support for a universal Open Access explanation, and no empirical support for Early View. There was some inferential support for a Quality Differential brought about by more highly-citable articles being deposited in the arXiv. In spite of their citation advantage, arXiv-deposited articles received 23% fewer downloads from the publisher’s website (about 10 fewer downloads per article) in all but the most recent two years after publication. The data suggest that arXiv and the publisher’s website may be fulfilling distinct functional needs of the reader.

173 citations


Journal ArticleDOI
TL;DR: It is found that there is a consistent high degree of cross-disciplinarity in the cognitive practices of research but a more erratic and narrower degree in the social dimensions.
Abstract: Nanotechnology has been presented in the policy discourse as an intrinsically interdisciplinary field, requiring collaborations among researchers with different backgrounds, and specific funding schemes supporting knowledge-integration activities Early bibliometric studies supported this interdisciplinary vision (Meyer & Persson, 1998), but recent results suggest that nanotechnology is (yet) a mixed bag with various mono-disciplinary subfields (Schummer, 2004) We have reexamined the issue at the research project level, carrying out five case studies in molecular motors, a specialty of bionanotechnology Relying both in data from interviews and bibliometric indicators, we have developed a multidimensional analysis (Sanz-Menendez et al, 2001) in order to explore the extent and types of cross-disciplinary practices in each project We have found that there is a consistent high degree of cross-disciplinarity in the cognitive practices of research (ie, use of references and instrumentalities) but a more erratic and narrower degree in the social dimensions (ie, affiliation and researchers’ background) This suggests that cross-disciplinarity is an eminently epistemic characteristic and that bibliometric indicators based on citations and references capture more accurately the generation of cross-disciplinary knowledge than approaches tracking co-authors’ disciplinary affiliations In the light of these findings we raise the question whether policies focusing on formal collaborations between laboratories are the most appropriate to facilitate cross-disciplinary knowledge acquisition and generation

Journal ArticleDOI
TL;DR: To improve the quality and efficiency of stroke research, continuity in research focuses needs to be maintained, and thus funding should be allocated on a long-term basis to institutes with a proven record of success.
Abstract: As the population ages in Taiwan, stroke research has received greater attention in recent years. Strokes have significant impacts on the health and well-being of the elderly. To formulate future research policy, information on stroke publications should be collected. In this research, we studied stroke-related research articles published by Taiwan researchers which were indexed in the Science Citation Index from 1991 to 2005. We found that the quantity of publications has increased at a quicker pace than the worldwide trend. Over the years, there has been an increase in international collaboration, mainly with researchers in the U.S. Article visibility, measured as the frequency of being cited, also increased during the period. It appears that stroke research in Taiwan has become more globally connected and has also improved in quality. The publication output was concentrated in a few institutes, but there was a wide variation among these institutes in the ability to independently conduct research. A wide array of keywords indicated a probable lack of continuity in research. Nevertheless, there was an inverse relationship between stroke mortality and number of published articles in Taiwan. To improve the quality and efficiency of stroke research, continuity in research focuses needs to be maintained, and thus funding should be allocated on a long-term basis to institutes with a proven record of success.

Journal ArticleDOI
TL;DR: It is suggested that h-indices themselves may form the basis of a series of h-Indices at successively higher levels of aggregation.
Abstract: It is suggested that h-indices themselves may form the basis of a series of h-indices at successively higher levels of aggregation. The concept of successive h-indices may usefully contribute to develop a coherent frame for multi-level assessments.

Journal ArticleDOI
TL;DR: The Journal Citation Reports of the Science Citation Index 2004 were used to delineate a core set of nanotechnology journals and a nanotechnology-relevant set; in comparison with 2003, the core set has grown and the relevant set has decreased, suggesting a higher degree of codification in the field of nan technology.
Abstract: The Journal Citation Reports of the Science Citation Index 2004 were used to delineate a core set of nanotechnology journals and a nanotechnology-relevant set. In comparison with 2003, the core set has grown and the relevant set has decreased. This suggests a higher degree of codification in the field of nanotechnology: the field has become more focused in terms of citation practices. Using the citing patterns among journals at the aggregate level, a core group of ten nanotechnology journals in the vector space can be delineated on the criterion of betweenness centrality. National contributions to this core group of journals are evaluated for the years 2003, 2004, and 2005. Additionally, the specific class of nanotechnology patents in the database of the U. S. Patent and Trade Office (USPTO) is analyzed to determine if non-patent literature references can be used as a source for the delineation of the knowledge base in terms of scientific journals. The references are primarily to general science journals and letters, and therefore not specific enough for the purpose of delineating a journal set.

Journal ArticleDOI
TL;DR: It is suggested that N&N is often misconstrued as either a field of technology or an area of (broadly) converging technologies while evidence to date suggests rather that N &N be considered a set of inter-related and overlapping about not necessarily merging technologies.
Abstract: This contribution formulates a number of propositions about the emergence of novel nanoscience and nanotechnology (N&N). Seeking to complement recent work that aims to define a research agenda and draws on general insights from the innovation literature, this paper aims to synthesize knowledge from innovation-related studies of the N&N field. More specifically, it is suggested that N&N is often misconstrued as either a field of technology or an area of (broadly) converging technologies while evidence to date suggests rather that N&N be considered a set of inter-related and overlapping about not necessarily merging technologies. The role of instrumentation in connecting the various N&N fields is underlined. Finally, the question is raised whether change in N&N tends to be incremental rather than discontinuous, being the result of technological path-dependencies and lock-ins in industry-typical search regimes that are only slowly giving way to more boundary-crossing activities.

Journal ArticleDOI
TL;DR: Based on a survey of 1554 researchers funded by the Natural Sciences and Engineering Research Council of Canada, the results of the multivariate regressions indicate that various factors explain the decision of whether or not to collaborate with industry and the government.
Abstract: This paper addresses four questions: What is the extent of the collaboration between the natural sciences and engineering researchers in Canadian universities and government agencies and industry? What are the determinants of this collaboration? Which factors explain the barriers to collaboration between the university, industry and government? Are there similarities and differences between the factors that explain collaboration and the barriers to collaboration? Based on a survey of 1554 researchers funded by the Natural Sciences and Engineering Research Council of Canada (NSERC), the results of the multivariate regressions indicate that various factors explain the decision of whether or not to collaborate with industry and the government. The results also differed according to the studied fields. Overall, the results show that the variables that relate to the researcher’s strategic positioning, to the set-up of strategic networks, to the costs related to the production of the transferred knowledge and transactions explain in large part the researcher’s collaboration. The results of the linear regression pointed to various factors that affect collaboration with researchers: research budget, university localization, radicalness of research, degree of risk-taking culture and researcher’s publications. Finally, the last part of the paper presents the results, and what they imply for future research and theory building.

Journal ArticleDOI
TL;DR: The authors present ranked lists of world’s countries — with main focus on EU countries (together with newly acceeded and candidate countries) — by their h-index on various science fields, attempting to fit a recent theoretical model relating the h- index with two traditional scientometric indicators: the number of publications and the mean citation rate.
Abstract: The authors present ranked lists of world’s countries — with main focus on EU countries (together with newly acceeded and candidate countries) — by their h-index on various science fields. As main source of data Thomson Scientific’s Essential Science Indicators (ESI) database was used. EU countries have strong positions in each field but none of them can successfully compete with the USA. The modest position of the newly accessed and candidate countries illustrate the importance of supportive economic and political background in order to achieve scientific success. An attempt is made to fit a recent theoretical model relating the h-index with two traditional scientometric indicators: the number of publications and the mean citation rate.

Journal ArticleDOI
Răzvan V. Florian1
TL;DR: In the Shanghai ranking, the dependence between the score for the SCI indicator and the weighted number of considered articles obeys a power law, instead of the proportional dependence that is suggested by the official methodology of the ranking.
Abstract: I discuss the difficulties that I encountered in reproducing the results of the Shanghai ranking of world universities. In the Shanghai ranking, the dependence between the score for the SCI indicator and the weighted number of considered articles obeys a power law, instead of the proportional dependence that is suggested by the official methodology of the ranking. Discrepancies from proportionality are also found in some of the scores for the N&S and Size indicators. This shows that the results of the Shanghai ranking cannot be reproduced, given raw data and the public methodology of the ranking.

Journal ArticleDOI
TL;DR: A new kind of objects of study is introduced, the class of cumulative-turnout networks for objects ofStudy, containing full information on cooperation, which leads to an interpretation of the results of score functions and to the definition of new indicators for scientific cooperation.
Abstract: The literature on publication counting demonstrates the use of various terminologies and methods. In many scientific publications, no information at all is given about the counting methods used. There is a lack of knowledge and agreement about the sort of information provided by the various methods, about the theoretical and technical limitations for the different methods and about the size of the differences obtained by using various methods. The need for precise definitions and terminology has been expressed repeatedly but with no success. Counting methods for publications are defined and analysed with the use of set and measure theory. The analysis depends on definitions of basic units for analysis (three chosen for examination), objects of study (three chosen for examination) and score functions (five chosen for examination). The score functions define five classes of counting methods. However, in a number of cases different combinations of basic units of analysis, objects of study and score functions give identical results. Therefore, the result is the characterization of 19 counting methods, five complete counting methods, five complete-normalized counting methods, two whole counting methods, two whole-normalized counting methods, and five straight counting methods. When scores for objects of study are added, the value obtained can be identical with or higher than the score for the union of the objects of study. Therefore, some classes of counting methods, including the classes of complete, complete-normalized and straight counting methods, are additive, others, including the classes of whole and whole-normalized counting methods, are non-additive. An analysis of the differences between scores obtained by different score functions and therefore the differences obtained by different counting methods is presented. In this analysis we introduce a new kind of objects of study, the class of cumulative-turnout networks for objects of study, containing full information on cooperation. Cumulative-turnout networks are all authors, institutions or countries contributing to the publications of an author, an institute or a country. The analysis leads to an interpretation of the results of score functions and to the definition of new indicators for scientific cooperation. We also define a number of other networks, internal cumulative-turnout networks, external cumulative-turnout networks, underlying networks, internal underlying networks and external underlying networks. The networks open new opportunities for quantitative studies of scientific cooperation.

Journal ArticleDOI
TL;DR: This paper analyses the state of the art of nanotechnology from an economic perspective, by presenting data on markets, funding, companies, patents and publications and raising the question of how much of the nano-hype is founded on economic data and how much is based on wishful thinking.
Abstract: Nanotechnology merits having a major impact on the world economy because its applications will be used in virtually all sectors. Scientists, researchers, managers, investors and policy makers worldwide acknowledge this huge potential and have started the nano-race. The purpose of this paper is to analyse the state of the art of nanotechnology from an economic perspective, by presenting data on markets, funding, companies, patents and publications. It will also raise the question of how much of the nano-hype is founded on economic data and how much is based on wishful thinking. It focuses on a comparison between world regions, thereby concentrating on Europe and the European Union in relation to their main competitors — the United States and Japan and the emerging ‘nano-powers’ China and Russia.

Journal ArticleDOI
TL;DR: Multivariate methods were successfully employed in a comprehensive scientometric analysis of geostatistics research, and the publications data for this research came from the Science Citation Index and spanned the period from 1967 to 2005.
Abstract: Multivariate methods were successfully employed in a comprehensive scientometric analysis of geostatistics research, and the publications data for this research came from the Science Citation Index and spanned the period from 1967 to 2005. Hierarchical cluster analysis (CA) was used in publication patterns based on different types of variables. A backward discriminant analysis (DA) with appropriate statistical tests was then conducted to confirm CA results and evaluate the variations of various patterns. For authorship pattern, the 50 most productive authors were classified by CA into 4 groups representing different levels, and DA produced 92.0% correct assignment with high reliability. The discriminant parameters were mean impact factor (MIF), annual citations per publication (ACPP), and the number of publications by the first author; for country/region pattern, CA divided the top 50 most productive countries/regions into 4 groups with 95.9% correct assignments, and the discriminant parameters were MIF, ACCP, and independent publication (IP); for institute pattern, 3 groups were identified from the top 50 most productive institutes with nearly 88.0% correct assignment, and the discriminant parameters were MIF, ACCP, IP, and international collaborative publication; last, for journal pattern, the top 50 most productive journals were classified into 3 groups with nearly 98.0% correct assignment, and its discriminant parameters were total citations, impact factor and ACCP. Moreover, we also analyzed general patterns for publication document type, language, subject category, and publication growth.

Journal ArticleDOI
TL;DR: This work re-analyse a previously published data set which reveals that in many cases the h-rate, according to theory, is not constant, and suggests ways in which deeper scientometric investigations could be carried out.
Abstract: Hirsch’s h-index gives a single number that in some sense summarizes an author’s research output and its impact. Since an individual author’s h-index will be time-dependent, we propose instead the h-rate which, according to theory, is (almost) constant. We re-analyse a previously published data set (Liang, 2006) which, although not of the precise form to properly test our model, reveals that in many cases we do not have a constant h-rate. On the other hand this then suggests ways in which deeper scientometric investigations could be carried out. This work should be viewed as complementary to that of Liang (2006).

Journal ArticleDOI
TL;DR: As results, the size of invention and the degree of dependence upon Japanese technological domain significantly affect patent citation counts of KIST.
Abstract: Patent citation counts represent an aspect of patent quality and knowledge flow. Especially, citation data of US patents contain most valuable pieces of the information among other patents. This paper identifies the factors affecting patent citation counts using US patents belonging to Korea Institute of Science and Technology (KIST). For patent citation count model, zero-inflated models are announced to handle the excess zero data. For explanatory factors, research team characteristics, invention-specific characteristics, and geographical domain related characteristics are suggested. As results, the size of invention and the degree of dependence upon Japanese technological domain significantly affect patent citation counts of KIST.

Journal ArticleDOI
TL;DR: The proposed set of indexes accurately summarizes both the success and evolution of scientists’ careers in Spain, and it may be useful in the evaluation of other not well established national scientific research systems.
Abstract: The applicability of Hirsch’s h index (Hirsch, 2005) for evaluating scientific research in Spain has been investigated. A series of derivative indexes that take into account: i) the overall low scientific production in Spain before the’ 80s; ii) differences among areas due to size (overall number of citations for publications in a given area); and iii) the number of authors, are suggested. Their applicability has been tested for two different areas in the Biological Sciences. The proposed set of indexes accurately summarizes both the success and evolution of scientists’ careers in Spain, and it may be useful in the evaluation of other not well established national scientific research systems.

Journal ArticleDOI
TL;DR: It is shown that author’s self-citation patterns reveal important information on the development and emergence of new research topics over time, and a network based definition of field mobility is introduced, using the Optimal Percolation Method.
Abstract: This paper introduces a new approach to detecting scientists’ field mobility by focusing on an author’s self-citation network, and the co-authorships and keywords in self-citing articles. Contrary to much previous literature on self-citations, we will show that author’s self-citation patterns reveal important information on the development and emergence of new research topics over time. More specifically, we will discuss self-citations as a means to detect scientists’ field mobility. We introduce a network based definition of field mobility, using the Optimal Percolation Method (LAMBIOTTE & AUSLOOS, 2005; 2006). The results of the study can be extended to selfcitation networks of groups of authors and, generally also for other types of networks.

Journal ArticleDOI
TL;DR: This paper analyses two large datasets of bibliometric information extracted from ISI and adopts an empirical network approach to try to uncover the fine structure of the relevant micro-innovation systems and the mechanisms through which these evolve along trajectories of change shaped by the search for solutions to interdependent problems.
Abstract: Innovation in medicine is a complex process that unfolds unevenly in time and space. It is characterised by radical uncertainty and emerges from innovation systems that can hardly be comprehended within geographical, technological or institutional boundaries. These systems are instead highly distributed across countries, competences and organisations. This paper explores the nature, rate and direction of the growth and transformation of medical knowledge in two specific areas of research, interventional cardiology and glaucoma. We analyse two large datasets of bibliometric information extracted from ISI and adopt an empirical network approach to try to uncover the fine structure of the relevant micro-innovation systems and the mechanisms through which these evolve along trajectories of change shaped by the search for solutions to interdependent problems.

Journal ArticleDOI
TL;DR: Text mining was used to extract technical intelligence from the open source global nanotechnology and nanoscience research literature and factor matrices quantified further the strength of the linkages among institutions and among countries, and validated the co-publishing networks shown graphically on the maps.
Abstract: Text mining was used to extract technical intelligence from the open source global nanotechnology and nanoscience research literature. An extensive nanotechnology/nanoscience-focused query was applied to the Science Citation Index/Social Science Citation Index (SCI/SSCI) databases. The nanotechnology/nanoscience research literature infrastructure (prolific authors, key journals/institutions/countries, most cited authors/journals/documents) was obtained using bibliometrics. A novel addition was the use of institution and country auto-correlation maps to show co-publishing networks among institutions and among countries, and the use of institution-phrase and country-phrase cross-correlation maps to show institution networks and country networks based on use of common terminology (proxy for common interests). The use of factor matrices quantified further the strength of the linkages among institutions and among countries, and validated the co-publishing networks shown graphically on the maps.

Journal ArticleDOI
TL;DR: Results suggest that it is not only the sheer quantity of publications that causes scientists to produce creative pieces of work but their ability to effectively communicate with otherwise disconnected peers and to address a broader work spectrum also enhances their chances to be widely cited and to develop novel ideas.
Abstract: While some believe that publication and citation scores are key predictors of breakthroughs in science, others claim that people who work at the intersection of scientific communities are more likely to be familiar with selecting and synthesizing alternatives into novel ideas. This paper contributes to this controversy by presenting a longitudinal comparison of highly creative scientists with equally productive researchers. The sample of creative scientists is identified by combining information on science awards and nominations by international peers covering research accomplishments in the mid-1990s. Results suggest that it is not only the sheer quantity of publications that causes scientists to produce creative pieces of work. Rather, their ability to effectively communicate with otherwise disconnected peers and to address a broader work spectrum also enhances their chances to be widely cited and to develop novel ideas.

Journal ArticleDOI
TL;DR: Citation frequency was significantly augmented by nation oriented citation bias, which seems to mainly influence the cumulative citation number for papers originating from the countries with a larger research output.
Abstract: Context. The use of citation frequency and impact factor as measures of research quality and journal prestige is being criticized. Citation frequency is augmented by self-citation and for most journals the majority of citations originate from a minority of papers. We hypothesized that citation frequency is also associated with the geographical origin of the research publication. Objective. We determined whether citations originate more frequently from institutes that are located in the same country as the authors of the cited publication than would be expected by chance. Design. We screened citations referring to 1200 cardiovascular publications in the 7 years following their publication. For the 1200 citation recipient publications we documented the country where the research originated (9 countries/regions) and the total number of received citations. For a selection of 8864 citation donor papers we registered the country/region where the citing paper originated. Results. Self-citation was common in cardiovascular journals (n = 1534, 17.8%). After exclusion of self-citation, however, the number of citations that originated from the same country as the author of the citation recipient was found to be on average 31.6% higher than would be expected by chance (p<0.01 for all countries/regions). In absolute numbers, nation oriented citation bias was most pronounced in the USA, the country with the largest research output (p<0.001). Conclusion. Citation frequency was significantly augmented by nation oriented citation bias. This nation oriented citation behaviour seems to mainly influence the cumulative citation number for papers originating from the countries with a larger research output.

Journal ArticleDOI
TL;DR: Validity of evaluative citation counting is limited because at least one quarter refers to perfunctory citations exhibiting a very low information utility level and by the fact that existing citation-databases refer to journal articles only.
Abstract: In reference to the increasing significance of citation counting in evaluations of scientists and science institutes as well as in science historiography, it is analyzed empirically what is cited in which frequency and what types of citations in scientific texts are used. Content analyses refer to numbers of references, self-references, publication language of references cited, publication types of references cited, and type of citation within the texts. Validity of citation counting is empirically analyzed with reference to random samples of English and German journal articles as well as German textbooks, encyclopedias, and test-manuals from psychology. Results show that 25% of all citations are perfunctory, more than 50% of references are journal articles and up to 40% are books and book-chapters, 10% are self-references. Differences between publications from various psychological sub-disciplines, publication languages, and types of publication are weak. Thus, validity of evaluative citation counting is limited because at least one quarter refers to perfunctory citations exhibiting a very low information utility level and by the fact that existing citation-databases refer to journal articles only.