CRANV2
Aslib Cranfield Research Project: Factors Determining the Performance of Indexing Systems: Volume 2
Citation indexing and bibliographic coupling
chapter
Cyril Cleverdon
Michael Keen
Cranfield
An investigation supported by a grant to Aslib by the National Science Foundation.
Use, reproduction, or publication, in whole or in part, is permitted for any purpose of the United States Government.
75
7O
R 60
E
C
A
L 50
L
R
A 40
T
I
O
30
2O
10
0.01
- 248 -
FIGURE 7.8T
Index Language Citation Indexing and Bibliographic Coupling
Document Relevance 1
Number of Documents in Collection
Number of Questions 35
Number of Relevant Documents 18
Generality Number 0.4
1400
Coupling
Strength
1
2
3
4
5
6
7+
Documents
Retrieved
Rel. Non-rel.
I0
7 194
5 84
2 41
2 28
2 18
2 12
RecaLl
Ratio
55.5%
38.9%
27.8%
11.1%
11.1%
11.1~
11.1%
Precision
Ralio
3.5%
5.6%
4.7%
6.7%
i0.0%
14. 370
Fallout
Ratio
0.396%
o.171%
0. 084%
0.057%
0,037%
0. 024%
FALLOUT
10
FIGURE 7.9P
REC[OCRerr]ALL/FALLOUT GRAPH FOR PERFORMANCE WITH
BIBLIOGRAPHIC COUPLING FOR IX)CUMENTS OF
FOUR GRADES OF RELEVANCE, WITH 1400 DOCUMENT
COLLECTION AND 35 SEVEN-STARTING-TERM
QUESTIONS.
100