CRANV2
Aslib Cranfield Research Project: Factors Determining the Performance of Indexing Systems: Volume 2
Methods for presentation of 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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Coordination
Level
1
2
3
4
5
Documents Recall Precision
Retrieved Ratio Ratio
Rel Non-Rel a/a+ c a]a+ b
(a) (b)
133 16,492 95. 0% 0. 8%
108 6,642 77. I% 1.6%
80 1,825 57.1% 4. 2%
57 430 40. 7% 11.7%
39 94 27. 9% 29. 3%
Relevant Documents (a + c) = 140
Generality number 5.
IOO
9o
8o
70
60
..J
...J
<t
a:
40
3o
2o
\
,,,,,
I0
0
IO
30 40 50 60 70 80 90 I00
% PRECISION
FIGURE 3.3TP
TABLE AND PLOT OF TEST RESULTS FOR 20 SEARCHES
SHOWING RECALL AND PRECISION RATIOS FOR SEARCH X.