Transcript Scopustm, Google Scholar, Web of knowledge: Too much or

Scopus, Google Scholar,
Web of knowledge:
Too much or not too much?
ICOLC Autumn 2005
7th European Meeting - Poznan, Poland
Ezio Tarantino
Con la collaborazione con Mary Joan Crowley
BIDS – Biblioteca digitale della Sapienza
University of Rome “La Sapienza”
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University of Rome “La Sapienza”
• 1999: BIDS (digital library) is born (10
databases)
• 2001: Web of Science
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University of Rome “La Sapienza”
Usage statistics (2002)
database
PsycINFO
Medline
Current Contents
GeoRef
WOS
searches/ month
25.387,42
22.472,7
7.569,9
3.561,42
2.124,20
3
University of Rome “La Sapienza”
Usage statistics (2002)
Searches/month 2002
30.000,0
25.000,0
20.000,0
15.000,0
Serie1
10.000,0
5.000,0
0,0
PsycINFO
Medline
cc
GeoRef
WOS
4
University of Rome “La Sapienza”
Usage statistics (2002)
database
WOS+CC
GeoRef
PsycINFO
Medline
euro/search
0,63
0,18
0,04
0,03
5
University of Rome “La Sapienza”
Usage statistics (2002)
euro/search 2002
0,8
0,6
0,4
Serie1
0,2
0
WOS+CC
GeoRef
PsycINFO
Medline
6
University of Rome “La Sapienza”
2003
WOS
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University of Rome “La Sapienza”
How many
many times
times has
has that
my article
•• How
article been
been
cited?
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University of Rome “La Sapienza”
2004, July
Scopus trial.
Pre-release version
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University of Rome “La Sapienza”
2004, October
Coverage & overlap
Database
Nr. of sourc es
Nr. of sourc es in Perc entage
(journals etc .)
SCOPUS
sourc es
in the DB *
SCOPUS
PsycInfo
1960
1270
64,75%
ASFA
5434
2005
36,89%
Econlit
973
377
38,74%
Biological Sciences
6426
2810
43,72%
Sociological abstracts
1865
751
40,80%
* source: CSA
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University of Rome “La Sapienza”
2004, November
Start-up of Google Scholar
2005, January
Signed contract with SCOPUS
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A quantitative evaluation
How many articles?
How many citations?
12
A quantitative evaluation
Number of articles
WOS:
Scopus:
Google Scholar
35.000.000 articles
25.000.000
?
13
A quantitative evaluation
Time range
WOS:
Scopus:
Google Scholar
1990-2003
1996?
14
A quantitative evaluation
The test
10 articles per discipline (economics,
medicine, science, psychology) from
international journal, since 1968 until
2003.
15
A quantitative evaluation
The test
Number of positive answers
Scopus
WOS
Google
34 (85%) 21(52,5%) 38 (95%)
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A quantitative evaluation
Number of positive answers
40
35
30
25
Scopus
20
WOS
15
Google
10
5
0
Scopus
WOS
Google
17
A quantitative evaluation
The test
Number of citations
Scopus
292
WOS
362
Google
500
18
A quantitative evaluation
Number of citations (grand total)
600
500
400
Scopus
300
WOS
Google
200
100
0
Scopus
WOS
Google
19
A quantitative evaluation
The test
Number of citations by discipline
discipline
Scopus
Num. cit
Econom ics and finance
37
Medicine and biology
74
Psychology and psychiatry
93
Sciences (physics and chem .)
88
Total
292
WOS
Num. cit
33
54
119
156
362
Google Scholar
Num. cit
187
102
71
140
500
20
A quantitative evaluation
Number of citations by discipline
100%
90%
80%
70%
60%
50%
40%
30%
20%
10%
0%
Google Scholar
WOS
Scopus
Economy and
finance
Medicine and
biology
Psychology and
psychiatry
Sciences
(physics and
chemistry)
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A quantitative evaluation
The test
Average citations per article found
DB
articles
Scopus
34
WOS
21
Google Scholar
38
nr. citations average
292
8,59
362
17,24
500
13,16
22
A quantitative evaluation
Nr. of articles found and average citation per article
40
35
30
25
20
15
10
5
0
average citations per article
Scopus
articles found
WOS
Google
Scholar
23
A quantitative evaluation
The test
Articles by time range
year
<1990
<1996
>1996
Scopus
5 (5)
4 (7)
25 (28)
WOS Google Scholar
0 (5)
4 (5)
2 (7)
6 (7)
19 (28)
28 (28)
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A quantitative evaluation
Articles by time range
The test
Articles
found by year
100
80
60
Scopus
WOS
40
GS
20
GS
WOS
Scopus
0
< 1990
<1996
>1996
25
A qualitative evaluation
Test #1
Discipline: Psychology
Article: Hoffmann, L.W., The Influence of the Family Environment on
Personality: Accounting for Sibling Differences, di Hoffman (Psychological
Bulletin, 1991)
citations:
Scopus:
WOS:
GS:
51 (3 not found elsewhere)
81 (35 not found elsewhere)
33 (4 not found elsewhere)
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A qualitative evaluation
citations:
Scopus:
WOS:
GS:
51 (3 unique)
81 (35 unique)
33 (4 unique)
citations in common
WOS-Scopus:
WOS-GS:
Scopus-GS:
43/51
25/33
26/33
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A qualitative evaluation
citations:
Scopus:
WOS:
GS:
51 (3 unique)
81 (35 unique)
33 (4 unique)
citations in common
WOS+Scopus: (81+51)-43 = 89
WOS+GS:
(81+33)-25 = 89
Scopus+GS: (51+33)-26 = 58
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A qualitative evaluation
QUESTIONS
Advantage or disadvantage?
Is it “noise” or more information?
Who decides?
29
A qualitative evaluation
30
A qualitative evaluation
Test #2
Discipline: Economics and finance
Article: Frittelli. M.: The minimal Entropy Martingale Measure and the
Valuation Problem in Incomplete Markets, (Mathematical finance,
2000)
citations:
Scopus:
WOS:
GS:
36
32
116
31
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Epstein, L., and S. Zin, 1989, "Substitution, Risk Aversion, and the Temporal
Behavior of Consumption and Asset Returns: A Theoretical Framework,"
Econometrica, 57, 937–969.[ISI]
Epstein, L., and S. Zin, 1991, "Substitution, Risk Aversion, and the Temporal
Behavior of Consumption and Asset Returns: An Empirical Investigation," Journal of
Political Economy, 99, 263–286.[CrossRef][ISI]
 article [Frittelli, The minimal Entropy Martingale Measure and the Valuation
Problem in Incomplete Markets,] should be here
Gilboa, I., and D. Schmeidler, 1989, "Maxmin Expected Utility with Non-unique Prior,"
Journal of Mathematical Economics, 18, 141–153.[CrossRef][ISI]
Hansen, L., and T. Sargent, 1995, "Discounted Linear Exponential Quadratic
Gaussian Control," IEEE Transactions on Automatic Control, 40, 968–
971.[CrossRef][ISI]
33
34
Fritelli,
[F 00] M. Fritelli, (2000), The minimal entropy martingale measure and
the valuation problem in incomplete markets. Mathematical Finance,
Vol. 10, pp. 39{52
35
A qualitative evaluation
Test #3
Article: Buncel, E..: Rationalizing the regioselectivity in
polynitroarene anionic σ-adduct formation. Relevance to
nucleophilic aromatic substitution (Chemical Reviews 1995
(7), pp. X-2280 )
citations:
Scopus:
WOS:
GS:
3
65
15
36
A qualitative evaluation
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A qualitative evaluation
38
A qualitative evaluation
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A qualitative evaluation
Test #4 (The ghost article: an international plot)
Article:Ryckaert-Ciccotti: Numerical integration of the cartesian
equations of motion of a system with constraints: molecular
dynamics of n-alkanes. Journal of computation physics,
1977)
citations:
Scopus:
WOS:
GS:
not found
not found
cited by 1.276
40
A qualitative evaluation
41
A qualitative evaluation
42
A qualitative evaluation
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Conclusion
The winner is….
No winner!
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Thank you
[email protected]
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