Presentation at Wuhan University, Wuhan, China, April 15, 2019.

1. Large-scale visualization of science
Nees Jan van Eck
Centre for Science and Technology Studies (CWTS), Leiden University
Wuhan University
Wuhan, China, April 15, 2019

2. Bibliographic data sources
1
PATSTAT

3. Bibliographic data sources
2
Web of Science Scopus
Journals 20,000 24,000
Publications 55 million 45 million
Citations 1.2 billion 1.2 billion

4. Bibliometric networks
3
WoS
Scopus
Dimensions
PubMed
Crossref
Citation network
of pubs / journals / authors / orgs / countries
Co-authorship network
of authors / orgs / countries
Co-citation network
of pubs / journals / authors / orgs / countries
Co-occurrence network
of keywords / terms
Bibliographic coupling network
of pubs / journals / authors
Bibliographic
data source

5. Outline
• Software tools
• Network analysis techniques
• Algorithmically constructed classification system of science
4

6. Software tools
5

7. VOSviewer
6

8. Users of VOSviewer
• Researchers
• Research institutions
• Research funders
• Scientific publishers
• Industry
7

9. 8

10. 9

11. Development
10

12. Data access
11
Download

13. Interactive querying
12

14. 13

15. 14

16. CitNetExplorer
15

17. Network analysis
techniques
16

18. Network analysis techniques
17
Layout:
• AKA mapping
• Visualization of similarities (VOS)
Clustering:
• AKA community detection
• Leiden algorithm

19. VOS
18

20. Leiden algorithm
19

21. Algorithmic
classification systems
of science
20

22. CWTS publication-level classification system of
science
• Based on all articles in reviews in Web of Science between 2000 and 2017
• 21.2 million publications
• 374.1 million citation links
• Classification system of 3 hierarchical levels:
– 22 broad disciplines
– 868 fields
– 4,047 subfields
• Computational performance using the Leiden algorithm: less than 2hrs
21

23. 22
Structure of science based on 4,000 micro-level fields
Social sciences
and humanities
Biomedical and
health sciences Life and earth
sciences
Mathematics and
computer science
Physical
sciences and
engineering
Size of a field is
proportional to the
number of publications in
the field

24. 23
Structure of science based on 4,000 micro-level fields
Social sciences
and humanities
Biomedical and
health sciences Life and earth
sciences
Mathematics and
computer science
Physical
sciences and
engineering
Size of a field is
proportional to the
number of publications in
the field
Scientometrics

25. Summary of scientometrics subfield
24
Cluster: 145
No. publications: 16,312
Top 5 terms No. pubs
bibliometric analysis 852
impact factor 495
h index 264
peer review 515
citation 642
Top 5 publications No. cits
hirsch, je (2005). an index to quantify an individual's scientific research output. p natl acad sci usa, 102(46), 16569-16572. 2,635
wuchty, s; et al. (2007). the increasing dominance of teams in production of knowledge. science, 316(5827), 1036-1039. 699
egghe, l (2006). theory and practise of the g-index. scientometrics, 69(1), 131-152. 609
king, da (2004). the scientific impact of nations. nature, 430(6997), 311-316. 496
newman, mej (2004). coauthorship networks and patterns of scientific collaboration. p natl acad sci usa, 101, 5200-5205. 488
Top 5 authors No. pubs Top 5 journals No. pubs
bornmann, l 221 scientometrics 2,865
thelwall, m 202 journal of informetrics 700
leydesdorff, l 175 journal of the american society for information science and technology 613
rousseau, r 161 plos one 339
egghe, l 133 research evaluation 324
Top 5 institutes No. pubs Top 5 departments No. pubs
univ granada 316 sch lib & informat sci (indiana univ) 106
kathol univ leuven 256 amsterdam sch commun res ascor (univ amsterdam) 97
leiden univ 249 ctr sci & technol studies (leiden univ) 90
indiana univ 246 sch publ policy (georgia inst technol - atlanta) 88
univ wolverhampton 216 trend res ctr (asia univ) 84
0
200
400
600
800
1,000
1,200
1,400
1,600
2000 2002 2004 2006 2008 2010 2012 2014 2016
No.publications

26. Publications in scientometrics subfield
25

27. Term map of scientometrics field
26
Peer review,
OA, careers,
and gender
Collaboration
Scientometric
indicators and
networks
Medical research
Country-level
analyses

28. 27
Time-line map of highly cited scientometrics
publications

29. Overlay visualizations
28
Social sciences
and humanities
Biomedical and
health sciences Life and earth
sciences
Mathematics and
computer science
Physical
sciences and
engineering

30. Time trend
29
MicroRNA Graphene

31. Summary of graphene subfield
30
Cluster: 9
No. publications: 27,771
Top 5 terms No. pubs
bilayer graphene 836
epitaxial graphene 491
silicene 401
graphene nanoribbon 1,035
graphene field effect transistor 207
Top 5 publications No. cits
novoselov, ks; et al. (2004). electric field effect in atomically thin carbon films. science, 306(5696), 666-669. 27,743
geim, ak; et al. (2007). the rise of graphene. nat mater, 6(3), 183-191. 20,073
novoselov, ks; et al. (2005). two-dimensional gas of massless dirac fermions in graphene. nature, 438(7065), 197-200. 11,359
castro neto, ah; et al. (2009). the electronic properties of graphene. rev mod phys, 81(1), 109-162. 11,368
zhang, yb; et al. (2005). experimental observation of the quantum hall effect and berry's phase in graphene. nature, 438(7065), 201-204. 8,110
Top 5 authors No. pubs Top 5 journals No. pubs
watanabe, k 249 physical review b 4,013
taniguchi, t 240 applied physics letters 1,834
peeters, fm 233 carbon 994
lin, mf 178 nano letters 906
katsnelson, mi 177 journal of applied physics 841
Top 5 institutes No. pubs Top 5 departments No. pubs
chinese acad sci 1,394 dept phys (natl univ singapore) 257
russian acad sci 778 inst phys (chinese acad sci) 226
peking univ 557 inst mol & mat (radboud univ nijmegen) 216
natl univ singapore 482 dept phys (mit) 209
tsing hua univ 458 dept phys (univ calif berkeley and berkeley national lab) 206
0
500
1,000
1,500
2,000
2,500
3,000
3,500
4,000
2000 2002 2004 2006 2008 2010 2012 2014 2016
No.publications

32. Open access
31
Social sciences
and humanities
Biomedical and
health sciences Life and earth
sciences
Mathematics and
computer science
Physical
sciences and
engineering

33. Collaboration with industry
32
Social sciences
and humanities
Biomedical and
health sciences Life and earth
sciences
Mathematics and
computer science
Physical
sciences and
engineering

34. Collaboration with hospitals
33
Social sciences
and humanities
Biomedical and
health sciences Life and earth
sciences
Mathematics and
computer science
Physical
sciences and
engineering

35. Citations from patents
34
Social sciences
and humanities
Biomedical and
health sciences Life and earth
sciences
Mathematics and
computer science
Physical
sciences and
engineering

36. China’s publication output
35
Social sciences
and humanities
Biomedical and
health sciences Life and earth
sciences
Mathematics and
computer science
Physical
sciences and
engineering

37. China’s publication output and time trend
36
Social sciences
and humanities
Biomedical and
health sciences Life and earth
sciences
Mathematics and
computer science
Physical
sciences and
engineering

38. Wuhan University’s publication output
37
Social sciences
and humanities
Biomedical and
health sciences Life and earth
sciences
Mathematics and
computer science
Physical
sciences and
engineering

39. Wuhan University’s research strengths
38
Share of an area’s
highly cited
publications
authored by Wuhan
University
Nano carriers drug
delivery Sodium-ion
batteries
Remote sensing
GPS precise point
positioning
Dye-sensitized solar
cells
Catalysis
Image restoration
super resolution

40. Do it yourself!
39
www.vosviewer.com www.citnetexplorer.nl

41. Thank you for your attention!
40