CRANV2
Aslib Cranfield Research Project: Factors Determining the Performance of Indexing Systems: Volume 2
Main test results
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.
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FIGURE 4. 510T
Index Language I.l.a (S.T. Natural language. Coordination)
Exhaustivtty of Indexing 3
Search Rule A
Document Relevance 1- 4
Number of Documents in CoLlection 1.400
Number of Questions 20 (Subset 6)
Number of Relevant Documents 147
Generality Number 5.3
Coord- Documents Beca[OCRerr] Precision
/nation FaLlout
Retrieved Ratio
Level HaUo
Hel. Non-rel. RaUo
a]a+c a/a+b x y
b/b-[OCRerr]-d z
1 133
2 14,225 00.6%
114 4.704 0.0%
77.6% 50.804% 20 20 20
3 82 1.630 2.4% 16.808%
55.9% 20
4.9% 20 20
5.852% 20 20 20
4 47 236
5 32.0%
21 17.0%
24 0.826% 16 20 20
6 14.3%
10 46.7%
3 0.086%
6.8% 9 20
76.9% 20
0.011% 2 20 20
7 4 0 2.7% 1O0.0[OCRerr] 0.000% 2 20 20
FIGURE 4.511T
Index Language i.6.a (S.T. Synonyms. Quasi-synonyms, Word forms. Coordination)
Exhaustivity of Indexing 3
Search Rule A
Document Relevance I - 4
Number of Documents in CoLlection 1,400
Number of Questions 20 (Subset 6)
Number of Relevant Documents 147
Generality Number 5.3
Coord- Documents
ination RecaU Precision Fallout
Level Retrieved Ratio
Hel. Non-tel. RaUo
a/a+c Halo
a/a+b b/b+d x y
1 142 (-)
2 126 96.6% (-) (_) 20 0 20
3 8,o88.
lO9 87.6%
4,657 1.6%*
74.1% 39.036%*
2.3% 20
16.720% 13" 20
20
4 20 20
69
5 t,276
36 46.9% 5.1%
24.5% 4.581% 20 20 20
6 226
19 32 13.7%
12.9% 0.811%
37.3% 16
0.115% 20 2O
8
7 20 20
8 t 5.4% 88.9% 0.004% 3 2O 2O
FIGURE 4. 512T
Index Language l.l.a (S.T. Natural language.
Exhaustivity of Indexing 3
Search Rule C
Document Relevance 1 - 4
Number of Documents in Collection 1,400
Number of Questions 20 (Subset 6)
Number of Relevant Documents see table
Generality Number see table
Coordination)
Coord-
ination
Level
R elevant GeneralRy Documents Recall
Documents Precision Fallout
Number Retrieved x y z
Rel. Non-rel. Ratio Ratio Ratio
147 5.3 128 (-) 0
147 87.1% (-) (-) 20 20
5.3 96
119 1,609" 65.3%
5.0 5.0%* 6.495=f[OCRerr] 20 13" 20
57 533 47.9% 9.7% 2.251% 17 17 17
94 4.6 26 63
43 27;7% 0.323% 9 14 14
4.4 29.2%
7 8 16.3%
21 46.7% 0.082% 2 7
5,0 7
1 2 4.8% 33.3% 0.048% 1 3 3