1. Advanced bibliometric software
tools for publishers and editors
Nees Jan van Eck
Centre for Science and Technology Studies (CWTS), Leiden University
Training course on “Big data and academic publication”
National Science Library, CAS, Beijing, China, June 22, 2016

2. About myself (1)
• Master in computer science
• PhD thesis on bibliometric
mapping of science
• Researcher at CWTS since 2009
– Bibliometric network analysis and
visualization
– Bibliometric indicators of research
performance
• Head of ICT
• Board member
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3. About myself (2)
• Editorial board member of
– Journal of the Association for Information Science and Technology
– Journal of Data and Information Science
– Journal of Informetrics
– Scientometrics
• Editor brief communications JASIST
• Board member ISSI
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4. Centre for Science and Technology
Studies (CWTS)
• Research center at Leiden University
focusing on science and technology
studies
• About 30 staff members
• History of more than 25 years in
bibliometric and scientometric
research
• Contract research
• Full access to large bibliographic
database (Web of Science and
Scopus)
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5. Bibliographic databases: ‘Big data’
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Web of Science Scopus
Journals 12,000 20,000
Publications 45 million 35 million
Citations 1 billion 0.9 billion

6. Bibliometric networks
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Web of
Science
Scopus
Citation network
of pubs / authors / journals
Co-authorship network
of authors / organizations
Co-citation network
of pubs / authors / journals
Co-occurrence network
of keywords / terms
Bibliographic coupling network
of pubs / authors / journals
Bibliographic
database

7. Software tools
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8. Software tools
• VOSviewer (www.vosviewer.com)
– Tool for constructing and visualizing bibliometric networks
• CitNetExplorer (www.citnetexplorer.nl)
– Tool for visualizing and analyzing citation networks of
publications
• Both tools have been developed together
with my colleague Ludo Waltman 7

9. VOSviewer
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10. VOSviewer
• Software tool for visualizing (bibliometric) networks
• Built-in support for popular bibliographic databases
– Web of Science
– Scopus
– PubMed
– RIS files
• Text mining functionality
• Layout and clustering techniques
• Advanced visualization features:
– Smart labeling algorithm
– Overlay visualizations
– Density visualizations (‘heat map’)
• Users:
– Researchers
– Professional users (e.g., universities, libraries, funders, publishers) 9

11. Increasing use of VOSviewer in
scientific publications
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12. CitNetExplorer
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13. Why use CitNetExplorer?
• To analyze the structure and development of a
research field
– Example: Identifying the main topics in the field of
scientometrics and tracing the developments within each topic
• To delineate a research area
– Example: Delineating the literature on science mapping
• To study publication oeuvres
– Example: Identifying the publications of a researcher and
analyzing the influence of cited and citing publications
• To support literature reviewing
– Example: Reviewing the literature on the h-index
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14. • Any type of bibliometric
network
• Co-authorship, direct citations,
co-citation, and bibliographic
coupling
• Time dimension is ignored
• Networks of at most ~10,000
nodes are supported
• Only citation networks of
publications
• Direct citation between
publications
• Time dimension is explicitly
considered
• Millions of publications are
supported
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VOSviewer CitNetExplorer

15. VOSviewer
demo
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16. Data
• Journals:
– Journal of the Association for Information Science and
Technology (JASIST)
– Journal of Informetrics
– Scientometrics
• Period: 2006-2015
• No. of publications: 5,150
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17. Term map
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18. Interpretation of a term map
• Size:
– The larger a term, the higher the frequency of occurrence of the
term
• Distance:
– In general, the smaller the distance between two terms, the
higher the relatedness of the terms, as measured by co-
occurrences
– The horizontal and vertical axes have no special meaning; maps
can be freely rotated and flipped
• Colors:
– Colors indicate clusters of closely related terms
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19. Term map – Average publication year
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20. Term map – Average citation impact
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21. Term map – Journal of Informetrics
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22. Term map - Scientometrics
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23. Term map - JASIST
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24. Term map - USA
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25. Term map - China
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26. Term map – The Netherlands
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27. Co-authorship map of authors
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28. Co-citation map of sources
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29. Bibliographic map of publications
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30. CitNetExplorer
demo
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31. More
information
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32. Do it yourself!
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www.vosviewer.com www.citnetexplorer.nl

33. Publications on VOSviewer
• Van Eck, N.J., & Waltman, L. (2014). Visualizing bibliometric networks. In Y.
Ding, R. Rousseau, & D. Wolfram (Eds.), Measuring scholarly impact: Methods
and practice (pp. 285-320). Springer. 10.1007/978-3-319-10377-8_13
• Van Eck, N.J., & Waltman, L. (2010). Software survey: VOSviewer, a computer
program for bibliometric mapping. Scientometrics, 84(2), 523-538.
10.1007/s11192-009-0146-3
• Waltman, L., Van Eck, N.J., & Noyons, E.C.M. (2010). A unified approach to
mapping and clustering of bibliometric networks. Journal of Informetrics,
4(4), 629-635. 10.1016/j.joi.2010.07.002
• Van Eck, N.J., Waltman, L., Dekker, R., & Van den Berg, J. (2010). A
comparison of two techniques for bibliometric mapping: Multidimensional
scaling and VOS. JASIST, 61(12), 2405-2416. 10.1002/asi.21421
• Waltman, L., & Van Eck, N.J. (2013). A smart local moving algorithm for large-
scale modularity-based community detection. European Physical Journal B,
86(11), 471. 10.1140/epjb/e2013-40829-0
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34. Publications on CitNetExplorer
• Van Eck, N.J., & Waltman, L. (2014). CitNetExplorer: A new software tool for
analyzing and visualizing citation networks. Journal of Informetrics, 8(4),
802-823. 10.1016/j.joi.2014.07.006
• Van Eck, N.J., & Waltman, L. (2014). Systematic retrieval of scientific literature
based on citation relations: Introducing the CitNetExplorer tool. In
Proceedings of the First Workshop on Bibliometric-enhanced Information
Retrieval (BIR 2014), pages 13-20. ceur-ws.org/Vol-1143/paper2.pdf
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35. Course: Bibliometric Network Analysis
and Science Mapping Using VOSviewer
• April 6-7, 2017
• Leiden University, The Netherlands
• Participants are introduced into the main
techniques for bibliometric network analysis and
science mapping
• Special attention is paid to applications in a
research evaluation and science policy context
• www.cwts.nl
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36. Thank you for your attention!
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