![An overview illustrates the construction and use of dual-map overlays. Citation arcs, cocitation links, and trajectories over time facilitate the study of multiple sets of publications at an interdisciplinary level, an organizational level, and the individual publication level. [Color figure can be viewed in the online issue, which is available at wileyonlinelibrary.com.]](https://www.researchgate.net/profile/Chaomei-Chen/publication/236039476/figure/fig7/AS:296582177148934@1447722109490/An-overview-illustrates-the-construction-and-use-of-dual-map-overlays-Citation-arcs_Q320.jpg)
![The initial appearance of the user interface, simultaneously showing citing and cited journal base maps. The base map of 10,330 citing journals is on the left. The base map of 10,253 cited journals is on the right. The colors depict clusters identified by Blondel's clustering algorithm. [Color figure can be viewed in the online issue, which is available at wileyonlinelibrary.com.]](https://www.researchgate.net/profile/Chaomei-Chen/publication/236039476/figure/fig1/AS:289157520871442@1445951933333/The-initial-appearance-of-the-user-interface-simultaneously-showing-citing-and-cited_Q320.jpg)
![The boundary of each cluster is shown to depict how its members are distributed. Clusters in both base maps overlap substantially. [Color figure can be viewed in the online issue, which is available at wileyonlinelibrary.com.]](https://www.researchgate.net/profile/Chaomei-Chen/publication/236039476/figure/fig9/AS:296582240063489@1447722124031/The-boundary-of-each-cluster-is-shown-to-depict-how-its-members-are-distributed-Clusters_Q320.jpg)
![Citation patterns in an overlay of 405 articles that cited the Wakefield et al. (1998) article. [Color figure can be viewed in the online issue, which is available at wileyonlinelibrary.com.]](https://www.researchgate.net/profile/Chaomei-Chen/publication/236039476/figure/fig4/AS:296582147788828@1447722102812/Citation-patterns-in-an-overlay-of-405-articles-that-cited-the-Wakefield-etal-1998_Q320.jpg)
![Citation patterns from 2005 to 2006 differ from those in 2004. In terms of the cited patterns, the citations to environment, toxicology, and nutrition in 2004 were no longer observable in 2005 to 2006. Instead, a group of new publications to history, philosophy, and records appeared. [Color figure can be viewed in the online issue, which is available at wileyonlinelibrary.com.]](https://www.researchgate.net/profile/Chaomei-Chen/publication/236039476/figure/fig11/AS:296582277812224@1447722133200/Citation-patterns-from-2005-to-2006-differ-from-those-in-2004-In-terms-of-the-cited_Q320.jpg)
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Patterns of Connections and Movements in Dual-Map Overlays: A New Method of Publication Portfolio Analysis
Abstract and Figures
Portfolio analysis of the publication profile of a unit of interest, ranging from individuals, organizations, to a scientific field or interdisciplinary programs, aims to inform analysts and decision makers about the position of the unit, where it has been, and where it may go in a complex adaptive environment. A portfolio analysis may aim to identify the gap between the current position of an organization and a goal that it intends to achieve or identify competencies of multiple institutions. We introduce a new visual analytic method for analyzing, comparing, and contrasting characteristics of publication portfolios. The new method introduces a novel design of dual-map thematic overlays on global maps of science. Each publication portfolio can be added as one layer of dual-map overlays over two related but distinct global maps of science, one for citing journals and the other for cited journals. We demonstrate how the new design facilitates a portfolio analysis in terms of patterns emerging from the distributions of citation threads and the dynamics of trajectories as a function of space and time. We first demonstrate the analysis of portfolios defined on a single source article. Then we contrast publication portfolios of multiple comparable units of interest, namely, colleges in universities, corporate research organizations. We also include examples of overlays of scientific fields. We expect the new method will provide new insights to portfolio analysis.
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... CiteSpace provides researchers with a comprehensive tool for exploring relationships among academic literature, gaining insights into the dynamics of disciplines, and discovering keywords and literatures within a research field. It is an important tool for research organizations, scholars, and policymakers to understand disciplinary trends and develop research strategies (26,27). In this study, the statistical values in CiteSpace were set as follows: select the top 50 levels of most cited or occurred items from each slice (Top N). ...
... As shown in Figure 2 In the Asian region, China [26] and India [26] dominate the research in related fields ( Figure 3). Further, a network study of the issuing countries ( Figure 4) reveals that the United States and European countries are still the main centers of research in the field of psychosexual constructs, and that the research on psychosexual in Asia as a whole is still relatively weak in comparison with Europe. ...
... As shown in Figure 2 In the Asian region, China [26] and India [26] dominate the research in related fields ( Figure 3). Further, a network study of the issuing countries ( Figure 4) reveals that the United States and European countries are still the main centers of research in the field of psychosexual constructs, and that the research on psychosexual in Asia as a whole is still relatively weak in comparison with Europe. ...
Psychosexual research has emerged as a cornerstone domain within psychology, medicine, and the social sciences, owing to its far-reaching implications for both individual well-being and broader societal dynamics. This multifaceted construct encompasses an intricate interplay of perceptions, emotional responses, attitudinal dispositions, and behavioral manifestations in the sexual context. Despite the field's significance, there exists a notable absence of comprehensive systematic analyses documenting its evolutionary trajectory and current state of knowledge. To address this significant gap in the literature, we conducted an extensive bibliometric analysis encompassing 1,365 psychosexual-related articles indexed in the Web of Science Core Collection spanning from 2000 to 2024. Our methodological framework incorporated multiple analytical dimensions, including temporal publication patterns, geographical and institutional distribution networks, co-citation analyses, subject area categorizations, and longitudinal keyword evolution patterns. The findings illuminate the fundamental architecture and developmental trajectory of psychosexual research, delineating key contributing nations, centers of academic excellence, and distinct thematic clusters within the field. Moreover, the analysis revealed emerging research frontiers and identified critical knowledge gaps requiring scholarly attention. This systematic investigation provides an empirically grounded assessment of the academic landscape, offering valuable insights into the structural dynamics and theoretical underpinnings of psychosexual research. The study serves as an essential resource for researchers and practitioners, providing strategic direction for future investigations by highlighting underexplored territories and fostering a more nuanced understanding of both theoretical frameworks and practical applications.
... The science community will use this information to identify: (i) academic tipping points in the giant panda population, diet speciality and genetic evolution, (ii) relations between various disciplines working on the problems, and (iii) knowledge development in giant panda research and Ursadae relation over time. (Chen, 2004(Chen, , 2016Chen et al., 2009;Chen and Leydesdorff, 2014). ...
... It has been extensively used in the fields of science assessment in a variety of research areas, including a report on the gut genomic content of giant pandas, DNA and cDNA research, the microbiome in giant pandas and to molecular evolution of Giant Panda over the past few million years (Guo et al., 2018). This paper shows how a scientometric analysis can detect the landscape of new subjects, as well as recent patterns and pivotal shifting points in the structure of the target domain (Chen, 2004(Chen, , 2016Chen et al., 2009;Chen and Leydesdorff, 2014). This approach was chosen because (i) massive bibliographic corpora are available (Web of Science and Scopus) (Bar-Ilan, 2008;Adriaanse and Rensleigh, 2013), (2) the availability of program packages for text mining and visualisation, such as CiteSpace (Chen, 2004(Chen, , 2016Chen et al., 2009;Chen and Leydesdorff, 2014). ...
... This paper shows how a scientometric analysis can detect the landscape of new subjects, as well as recent patterns and pivotal shifting points in the structure of the target domain (Chen, 2004(Chen, , 2016Chen et al., 2009;Chen and Leydesdorff, 2014). This approach was chosen because (i) massive bibliographic corpora are available (Web of Science and Scopus) (Bar-Ilan, 2008;Adriaanse and Rensleigh, 2013), (2) the availability of program packages for text mining and visualisation, such as CiteSpace (Chen, 2004(Chen, , 2016Chen et al., 2009;Chen and Leydesdorff, 2014). By reducing human bias, the visualised outcome of the scientometric evaluation will provide more thorough and reasoned research outcomes. ...
Giant panda conservation was one of the most successful in situ and ex situ conservation efforts in the world. The exclusivity herbivory evolution of Ailuropoda melanolueca from the Ursidae family sparks many interests in the dietetics research of said panda. Utilising data from 1079 Scopus and Web of Science-indexed journals from 1990 to 2020, this research conducted a depth scientometrics analysis for authors, countries and institutions conducting research closely related to giant pandas. Next, the study emphasises the burst analysis, cluster analysis and co-citation analysis to determine the top countries, research institutions, researchers and direction of research trends in Ailuropoda melanolueca research and its derivatives. The result shows from the exponential trend of research literature produced in the past 50 years that the Republic of China has dominated giant panda research, and second, in line is the United States of America. Based on overlay in trend analysis, there is substantial potential in economic-related research involving giant panda conservation.
... Bibliometrics is a scientific quantitative research method that uses the knowledge of statistics to systematically sort out the subject literature to better understand the knowledge foundation, knowledge structure and knowledge dissemination. Many fields employ bibliometrics to analyze scientific collaboration patterns, hot topics, and research trends in publications (Chen & Leydesdorff, 2014). Despite the long-standing development of research on economic growth and environmental pollution, there remains a need for fresh bibliometric studies that can visually present the field's new landscape to audiences. ...
The relationship between economic growth and environmental pollution has long been an area of study in economics. Increased global awareness of environmental protection has led to a surge in academic interest in this field. The main purpose of this study is to analyze the scientific output in this field on the basis of bibliometrics, understand the knowledge foundation and scientific collaboration patterns in this area, sort out the research evolution path, and predict future research trends. This paper analyzed 3,127 articles retrieved from the Web of Science repository. With CiteSpace software, network visualization analysis was performed, and knowledge maps were created to identify the most productive authors, institutions, countries, and journals, as well as influential highly cited literature. The most productive authors identified in the field were Bekun.F.Victor; The institution with the highest number of publications is the Chinese Academy of Sciences; China is the country that pays the most attention to the development of this field and obtains research results; The most influential article was "Investigation of environmental Kuznets curve for ecological footprint: The role of energy and financial development" published in Science of The Total Environment. Furthermore, the research results show that scholars' research topics of interest in this field have become more refined over time: Benefits from initial fossil energy consumption to renewable or clean energy; From traditional economic growth to focus on green total factor productivity; The study of environmental indicators ranges from single air pollution to greenhouse gases and ecological footprints. Currently green finance and green innovation are at the research frontiers in this area. Future research trends may focus on the economic and environmental benefits of new energy sources as a research topic.
... The results make known that a total of 1,038 journals have contributed articles related to the subject, and a collective 8,155 journals have been co-cited. A breakdown of the top 10 journals based on publication count and the top 10 co-cited journals by citation count is detailed in Table 3. 20 . Figure 4C meticulously illustrates the four principal citation pathways within the scienti c literature. ...
Background Fibrosis is the endpoint of the evolution of chronic diseases, resulting in disability and even death in obvious tissues or organs. Therefore, it is imperative to find effective diagnosis and treatment approaches for fibrosis. Numerous studies have confirmed the intimate association between connective tissue growth factor (CTGF) and fibrosis. CTGF, as a crucial growth factor in the formation and maintenance of connective tissue, is considered a primary driving factor in many progressive fibrotic diseases. Methods This investigation seeks to analyze CTGF's research trajectory in the realm of fibrosis and explore the research status and prevailing focal points. Relevant literature was found by searching the Web of Science Core Collection (WoSCC) from 2004 to 2024 and conducting bibliometric analysis and visualization through the utilization of CiteSpace, VOSviewer, and R software tools. Results Over the last two decades, there has been an upward trend in the overall volume of publications. China, the United States, and Japan are the major contributors to the output. The journal with the most published articles is PLOS ONE , while the most cited journal is the JOURNAL OF BIOLOGICAL CHEMISTRY . The author who has published the most papers and the most frequently co-cited author is Leask, Andrew. The top three keywords are "fibrosis," " Connective tissue growth factor," and "expression." Conclusions Through conducting a bibliometric analysis of this study, we have revealed the research status and hotspots of CTGF in fibrotic diseases, which provided potential research directions for researchers in this field.
... Figure 3C shows the dual-map overlay of academic journals, which clearly depicts the distribution of topics in journals involved in PPK model research. After importing the dataset into the atlas, citation trajectories are produced, and they are visualized as colored paths in the figure (Chen and Leydesdorff, 2014;Wang et al., 2024a). ...
Objective
Population pharmacokinetic (PPK) model is capable of identifying the factors that influence the variability of pharmacokinetic (PK) profiles and the degree of their influence, effectively reduces unexplained variability, and demonstrates excellent predictive ability. PPK model has been successfully constructed in several populations for a variety of drugs. However, no study has yet conducted a bibliometric analysis of publications related to the PPK model. This study aims to provide a comprehensive overview of the research progress and hotspots in the field of PPK model research through bibliometric methods.
Methods
A systematic search of the Web of Science database was conducted to collect articles and reviews related to the PPK model between 2000 and 2024. We then analyzed the data using Bibliometrix R package, Microsoft Office Excel, CiteSpace and VOSviewers.
Results
Between 2000 and 2024, we identified a total of 6,125 papers and 128,856 citations. The average annual growth rate of the relevant publications was 10.35%, showing continued growth momentum. These research outputs are concentrated in North America, Western Europe, and East Asia, with USA leading the way with 2,340 publications and having the highest H-index (93) and total citations (54,965). Uppsala University and British Journal of Clinical Pharmacology are the institutions with the highest publication output and the most influential journals, respectively. Most of the funding agencies are from the USA and the subject categories for most publications are Pharmacology Pharmacy. In terms of author contributions, professor Karlsson MO is the leader in the field with 149 publications. In addition, wo found that “critically ill patients,” “tacrolimus,” “machine learning,” “external evaluation,” “polymyxin b,” “voriconazole,” “extracorporeal membrane oxygenation,” “dose optimization” and “model-informed precision dosing” are current research hotspots and future research trends.
Conclusion
This study is the first comprehensive overview of the development of PPK model and research hotspots using bibliometric methods. Our findings provide researchers, especially beginners, with insights into the application area of PPK model, helping them to grasp key information in the field.
... On the left-hand side of the figure, the current status of research in disciplines related to TAM is depicted, while the right side represents the foundational research disciplines based on cited literature. Present research and research base are linked by the wave-shaped curve [40]. Two major areas of focus emerge: "Molecular, Biology, and Immunology," with "Medicine, Medical, and Clinical" on the left, and "Molecular, Biology, Genetics," and "Health, Nursing, and Medicine" on the right. ...
Objectives
Macrophages play a critical role in various diseases, including cancer, where their involvement is characterized by a dual nature. There is a growing focus on tumor-associated macrophages (TAMs) in cancer research due to their complex interactions with tumor biology. With the expanding body of research in this area, a retrospective analysis of published articles is warranted to gain insights into evolving trends. This bibliometric study aims to assist researchers in identifying key areas of interest and emerging directions within the field of TAM research.
Methods
A bibliometric analysis was performed using the Bibliometrix Package in R Software and CiteSpace software.
Results
The volume of research on TAMs continues to increase, with this study identifying major contributors to the field. The focus of research has shifted from traditional methods, such as flow cytometry and histological techniques, toward single-cell omics approaches, which offer unbiased insights into TAM heterogeneity. Current areas of interest include biomarkers, immune therapies, TAM states, tumor microenvironments, macrophage-targeted agents, and the response of TAMs to therapeutic interventions. These topics are anticipated to remain prominent in the near future.
Conclusion
The study provides an overview of annual publication trends, influential papers, key journals, frequently used keywords, leading authors, and contributing institutions. It also highlights the interdisciplinary evolution of TAM-related research and the connections between these areas of study.
... The colored lines represent citation pathways, highlighting the interrelationships between journals across different fields and revealing the connections between the applied (left) and cited (right) domains, which reflects the flow of knowledge at the journal level. 27,28 Clustering in the diagram was performed using the built-in Z-score algorithm, identifying two significant citation pathways, represented by the colors in the cited region, with line width proportional to the Z-scores of the citations. Z-score indicates the strength and significance of citation connections between journals. ...
Objective
Numerous studies have highlighted a link between COVID-19 and respiratory allergic conditions such as asthma and allergic rhinitis (AR). Despite the growing volume of research, there remains a notable gap in the form of a comprehensive bibliometric analysis that consolidates the findings on this association. This study aims to fill that gap by systematically exploring how asthma and AR interact with COVID-19.
Methods
By using the Web of Science Core Collection, we selected publications from January 2020 to October 2024 that related to COVID-19 and asthma/AR. Analysis tools such as VOSviewer and CiteSpace were employed to perform network mappings and citation analyses, focusing on co-authorship networks, keyword co-occurrences, and citation impacts to understand the research dynamics and collaborative patterns within this field.
Results
A collection of 553 publications was obtained, revealing an upward trend in research volume over the study period. The United States, China, and the United Kingdom were predominant in the research output, demonstrating extensive international collaborations. The study highlighted key areas of impact, such as the influence of asthma types on COVID-19 severity and the protective effects of specific treatments like inhaled corticosteroids and biologics. Emerging trends identified included the significance of socioeconomic factors and obesity in disease outcomes, as well as evolving strategies in vaccination and interventions.
Conclusion
This bibliometric analysis highlights the significant role of global research in exploring the interactions between COVID-19 and asthma/AR. It points out the reported safety and effectiveness of COVID-19 vaccines for these conditions and acknowledges the challenges in vaccine uptake among minority and socioeconomically disadvantaged groups. The study also identifies unique risks for children and obese patients during the pandemic and underscores the need for increased international collaboration and more comprehensive clinical trials, to evaluate the efficacy of treatments like inhaled corticosteroids and biologics.
... 24 The L/N (Logarithm/Normalization) parameter involves logarithmic and normalization processing of edge weights in the network, enhancing balance and preventing dominance by high-weight nodes. 25 The Latest Boundary Year (LBY) defines the temporal scope of the analysis, allowing researchers to focus on recent developments or long-term trends. 26 Finally, the edge threshold (e) controls the strength of connections in the literature network, filtering out weak connections to highlight strong associationsThese parameters, when adjusted appropriately, optimize the analysis results and provide deeper insights into scientific research trends. ...
Introduction
Venous thromboembolism (VTE) is a leading cause of cardiovascular-related deaths. Non-vitamin K antagonist oral anticoagulants (NOACs) offer effective therapy without injections or blood monitoring. This bibliometric analysis explores the research on NOACs for preventing VTE and pulmonary embolism.
Methods
Literature up to July 20, 2024, was searched in Web of Science Core Collection. Citespace software was used for screening and analysis.
Results
In this study, we analyzed 2124 articles and 767 reviews from 11,282 institutions across 528 countries and regions, encompassing 830 publications and 60 research directions. The USA led in publication count, followed by Germany and Canada. Cardiovascular System Cardiology, Hematology, and General Internal Medicine were the top research areas, while THROMBOSIS AND HAEMOSTASIS was the leading journal. From 2004 to 2024, we observed accelerated publication growth, particularly from 2008, highlighting the emergence of NOACs as a major research focus. Key contributors, including Bengt I. Eriksson, and major institutions like Harvard Medical School and University of Amsterdam, played pivotal roles in advancing anticoagulant research. Co-citation and keyword clustering analyses revealed research hotspots in NOACs, cancer-associated venous thromboembolism, stroke prevention, and COVID-19-related thrombotic events, reflecting a shift towards individualized anticoagulation therapy and the growing importance of NOACs in various clinical contexts.
Conclusion
The development of NOACs has progressed rapidly, with an increasing number of publications, indicating the lead research in the United States and other Western nations. Comparative studies on the safety and efficacy of NOACs have become a significant focus, shifting from traditional anticoagulants. Pharmacogenetics-guided use of NOACS shows new hope of precision medicine.
... International collaboration can help researchers in one country to access supplementary knowledge outside their own country (Bikard et al., 2015). It has been suggested that research collaborations and linkages are useful for understanding evolutionary themes and paradigm shifts in a field over time (Chen & Leydesdorff, 2014). The most frequently cited authors in the articles analysed in the current study were Creswell, J.W. (122 citations) and Lederman, N.G. ...
Inspired by the evolving nature of qualitative research, this study aims to examine the use of “qualitative survey”, a newer technique in qualitative data collection methods than interviews and observation. In addition to trends in research capacity, collaborations and research topics, the extent to which this data collection method has become widespread or accepted among researchers can provide insight into the future of this method. In this study, 743 studies published in the field of education between 1992 and 2024 from the Web of Science database were analysed. Web of Science database was searched with the keywords qualitative survey, qualitative questionnaire, open-ended questionnaire and open-ended survey. The results indicate a steady increase in the use of qualitative surveys as a data collection tool in educational research. After 2005, the number of publications has increased significantly. The countries with the highest number of publications and international co-operation are the USA, Türkiye and Australia. The most common keywords were higher education and teacher education. The analysis also revealed findings such as the most published authors, journals, publishers, most cited authors and articles.
We present a novel approach to visually locate bodies of research within the sciences, both at each moment of time and dynamically. This article describes how this approach fits with other efforts to locally and globally map scientific outputs. We then show how these science overlay maps help benchmark, explore collaborations, and track temporal changes, using examples of universities, corporations, funding agencies, and research topics. We address conditions of application, with their advantages, downsides and limitations. Overlay maps especially help investigate the increasing number of scientific developments and organisations that do not fit within traditional disciplinary categories. We make these tools accessible to help researchers explore the ongoing socio-cognitive transformation of science and technology systems. Comment: 40 pages, 6 Figures
A standard approach to large network visualization is to provide an overview of the network and a detailed view of a small component of the graph centred around a focal node. The user explores the network by changing the focal node in the detailed view or by changing the level of detail of a node or cluster. For scalability, fast force-based layout algorithms are used for the overview and the detailed view. However, using the same layout algorithm in both views is problematic since layout for the detailed view has different requirements to that in the overview. Here we present a model in which constrained graph layout algorithms are used for layout in the detailed view. This means the detailed view has high-quality layout including sophisticated edge routing and is customisable by the user who can add placement constraints on the layout. Scalability is still ensured since the slower layout techniques are only applied to the small subgraph shown in the detailed view. The main technical innovations are techniques to ensure that the overview and detailed view remain synchronized, and modifying constrained graph layout algorithms to support smooth, stable layout. The key innovation supporting stability are new dynamic graph layout algorithms that preserve the topology or structure of the network when the user changes the focus node or the level of detail by in situ semantic zooming. We have built a prototype tool and demonstrate its use in two application domains, UML class diagrams and biological networks. Index Terms—Graph drawing, constraints, stress majorization, force directed algorithms, multidimensional scaling.
Retracting published scientific articles is increasingly common. Retraction is a self-correction mechanism of the scientific community to maintain and safeguard the integrity of scientific literature. However, a retracted article may pose a profound and long-lasting threat to the credibility of the literature. New articles may unknowingly build their work on false claims made in retracted articles. Such dependencies on retracted articles may become implicit and indirect. Consequently, it becomes increasingly important to detect implicit and indirect threats. In this article, our aim is to raise the awareness of the potential threats of retracted articles even after their retraction and demonstrate a visual analytic study of retracted articles with reference to the rest of the literature and how their citations are influenced by their retraction. The context of highly cited retracted articles is visualized in terms of a co-citation network as well as the distribution of articles that have high-order citation dependencies on retracted articles. Survival analyses of time to retraction and postretraction citation are included. Sentences that explicitly cite retracted articles are extracted from full-text articles. Transitions of topics over time are depicted in topic-flow visualizations. We recommend that new visual analytic and science mapping tools should take retracted articles into account and facilitate tasks specifically related to the detection and monitoring of retracted articles.
Using the option Analyze Results with the Web of Science, one can directly generate overlays onto global journal maps of science. The maps are based on the 10,000+ journals contained in the Journal Citation Reports (JCR) of the Science and Social Sciences Citation Indices (2011). The disciplinary diversity of the retrieval is measured in terms of Rao-Stirling's “quadratic entropy” (Izsák & Papp, 1995). Since this indicator of interdisciplinarity is normalized between 0 and 1, interdisciplinarity can be compared among document sets and across years, cited or citing. The colors used for the overlays are based on Blondel, Guillaume, Lambiotte, and Lefebvre's (2008) community-finding algorithms operating on the relations among journals included in the JCR. The results can be exported from VOSViewer with different options such as proportional labels, heat maps, or cluster density maps. The maps can also be web-started or animated (e.g., using PowerPoint). The “citing” dimension of the aggregated journal–journal citation matrix was found to provide a more comprehensive description than the matrix based on the cited archive. The relations between local and global maps and their different functions in studying the sciences in terms of journal literatures are further discussed: Local and global maps are based on different assumptions and can be expected to serve different purposes for the explanation.
We report on the development of an interface to the US Patent and Trademark
Office (USPTO) that allows for the mapping of patent portfolios as overlays to
basemaps constructed from citation relations among all patents contained in
this database during the period 1976-2011. Both the interface and the data are
in the public domain; the freeware programs VOSViewer and/or Pajek can be used
for the visualization. These basemaps and overlays can be generated at both the
3-digit and 4-digit levels of the International Patent Classifications (IPC) of
the World Intellectual Property Organization (WIPO). The basemaps can provide a
stable mental framework for analysts to follow developments over searches for
different years, which can be animated. The full flexibility of the advanced
search engines of USPTO are available for generating sets of patents and/or
patent applications which can thus be visualized and compared. This instrument
allows for addressing questions about technological distance, diversity in
portfolios, and animating the developments of both technologies and
technological capacities of organizations over time.
A critical part of a scientific activity is to discern how a new idea is related to what we know and what may become possible. As the number of new scientific publications arrives at a rate that rapidly outpaces our capacity of reading, analyzing, and synthesizing scientific knowledge, we need to augment ourselves with information that can guide us through the rapidly growing intellectual space effectively. In this article, we address a fundamental issue concerning with what information may serve as early signs of potentially valuable ideas. In particular, we are interested in information that is routinely available and derivable upon the publication of a scientific paper without assuming the availability of additional information such as its usage and citations. We propose a theoretical and computational model that predicts the potential of a scientific publication in terms of the degree to which it alters the intellectual structure of the state of the art. The structural variation approach focuses on the novel boundary-spanning connections introduced by a new article to the intellectual space. We validate the role of boundaryspanning in predicting future citations using three metrics of structural variation, namely, modularity change rate, cluster linkage, and centrality divergence, along with more commonly studied predictors of citations such as the number of co-authors, the number of cited references, and the number of pages. Main
Global maps of science can be used as a reference system to chart career trajectories, the location of emerging research frontiers, or the expertise profiles of institutes or nations. This paper details data preparation, analysis, and layout performed when designing and subsequently updating the UCSD map of science and classification system. The original classification and map use 7.2 million papers and their references from Elsevier's Scopus (about 15,000 source titles, 2001-2005) and Thomson Reuters' Web of Science (WoS) Science, Social Science, Arts & Humanities Citation Indexes (about 9,000 source titles, 2001-2004)-about 16,000 unique source titles. The updated map and classification adds six years (2005-2010) of WoS data and three years (2006-2008) from Scopus to the existing category structure-increasing the number of source titles to about 25,000. To our knowledge, this is the first time that a widely used map of science was updated. A comparison of the original 5-year and the new 10-year maps and classification system show (i) an increase in the total number of journals that can be mapped by 9,409 journals (social sciences had a 80% increase, humanities a 119% increase, medical (32%) and natural science (74%)), (ii) a simplification of the map by assigning all but five highly interdisciplinary journals to exactly one discipline, (iii) a more even distribution of journals over the 554 subdisciplines and 13 disciplines when calculating the coefficient of variation, and (iv) a better reflection of journal clusters when compared with paper-level citation data. When evaluating the map with a listing of desirable features for maps of science, the updated map is shown to have higher mapping accuracy, easier understandability as fewer journals are multiply classified, and higher usability for the generation of data overlays, among others.
We explain the barycentre method and show how to apply it in a practical situation. A country's mean centre of publica-tion, or publication barycentre, is defined and its evolution is studied in the case of China's centre of publication. Data for this application are taken from the Chinese Science Cita-tion Database (CSCD). It is shown that China's publication barycentre slowly moves to the south and that it approaches the population barycentre. Tentative explanations for this southward movement, based on economic and educational considerations, are given. It is observed that inequality in publication between administrative units (regions) decreases slowly.
With the program HistCite™ it is possible to generate and visualize the most relevant papers in a set of documents retrieved from the Science Citation Index. Historical reconstructions of scientific developments can be represented chronologically as developments in networks of citation relations extracted from scientific literature. This study aims to go beyond the historical reconstruction of scientific knowledge, enriching the output of HistCite™ with algorithms from social-network analysis and information theory. Using main-path analysis, it is possible to highlight the structural backbone in the development of a scientific field. The expected information value of the message can be used to indicate whether change in the distribution (of citations) has occurred to such an extent that a path-dependency is generated. This provides us with a measure of evolutionary change between subsequent documents. The forgetting and rewriting of historically prior events at the research front can thus be indicated. These three methods - HistCite, main path and path dependent transitions - are applied to a set of documents related to fullerenes and the fullerene-like structures known as nanotubes.