Transcript Web of Science 1997-2007

Citation Analysis:
Some Historical, Sociological
And Philosophical Considerations
Henry Small, Chief Scientist and Director
Nancy Bayers, Manager
Research Services Group
Thomson Scientific
Colloque de l’Académie des Sciences, 14-15 Mai 2007
Evaluation des Publications Scientifiques
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Reference or Citation?
reference
citation
“It is impossible to separate them without
losing the rays of light that they send back
one to the other” (17th author)
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The Web of Science Story
1960
1965
Web of Science:
v3
v4
Arts & Humanities
Citation Index
Science Citation Index
1970
Social Sciences
Citation Index
1975
1980
1985
SciSearch
1990
SCI-CD
1995
2000
v5 v6
v7
2005
Century of Science
ISI Web of Knowledge
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Authors referenced in works of Aristotle
Author
References
Aristotle
121
Plato
120
Homer
100
Empedocles
97
Anaxagoras
64
Democritus
55
Euripides
51
Socrates
43
Pythagoras
39
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• 17th Century – Newton and the Principia
100 references to 50 authors
• Philosophical Transactions – the changing nature of citations
embedded references
footnotes
endnotes
• 18th Century – Lavoisier and the Traité
160 references to 60 authors
• Darwin and the Origin
750 references to books and articles
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Authors referenced by Einstein 1902 - 1909
Author
References
Einstein
32
Planck
15
Boltzmann
4
Lenard
4
Stark
4
Kirchhoff
4
Lorentz
4
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Impact Factor
All
Previous
Years
2003
2004
2006
2005
Immediacy Index
Citations
Source paper – published in 2005
Cited ½ Life
Cited reference – to item published in 2005
Cited reference to item – published in 2003 or 2004
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Percent of mean citations accounted for by top papers
100
90
80
% impact accounted
70
60
50
40
30
20
10
0
0
10
20
30
40
50
60
top percent of papers
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Individual paper metrics
69 Cites: Total citation count for selected
paper.
225 Cites2: 2nd generation cite count
based on total citations received by the
citing articles.
8.3 Expected Citation Rate: An average
rate of citation for all the papers of that
document type (articles, reviews, letters,
etc.), in that journal, for that selected year.
A journal-level metric.
8 Ratio: Ratio of expected to actual cites
Earth Sciences: Field: Subject area for the
journal in which the paper appeared.
0.229%: Percentile position of the paper
based on citations in the same field. A
field-level metric.
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Group of papers metrics: Iceland National Citation Report
2330 Total # papers and total # cites: combined
numbers for the set
4.6
Mean times cited: Total cites divided by total
papers.
1
Median times cited: Midpoint for citations
41
H-Index: Number of papers (N) in a given
dataset having N or more citations.
1.3
C-Index: Sum of all actual citations divided
by sum of all expected citations.
57.4 Average Percentile: average of the field
percentile measures which are based on
field and year of publication
0.03 Disciplinarity: reflects the level of
multidisciplinarity in a set of papers, ranging
from 0 to 1, where the lower the number, the
greater the multidisciplinarity. (Herfindal
Index)
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Identifying Research Fronts by Co-citation Links
1
2
3
citation
citing
paper
co-cited
papers
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2004 cluster of organic thin film transistors
n-type
rubrene
single crystals
thiophenes
ink jet printing, displays
pentacene
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Unity of science? Pathway from social science to astrophysics
Source: H. Small, A passage through science, Library Trends, 1999.
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URLs
• www.in-cites.com
• www.esi-topics.com
• www.sciencewatch.com
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Merci!
Henry Small
[email protected]
Nancy K. Bayers
[email protected]