CRANV2 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. - 184 o FIGURE 4.850T Index Language III. 5.a Exhauetivity of indexing 3 Search Rule F Document Relevance 1-4 Number of Documents in Collection Number of Questions 42 (subset 2) Number of Relevant Documents 198 Generality Number 23.0 200 (subset I) Coord- Starting ination Documents Terms Recall Precision Ratio Ratio Fallout Level Retrieved Rel. Non-tel. Ratio 2 0 156 1.660 1 146 78.0% 1,133 8.6% 73.7% 20.329% 2 114 11.4% 57.8% 13.817% 3 428 0 104 828 21.0% 52.5% 5.218% 1 100 534 14.2% 50.5% 7.657% 2 89 339 15.8% 44.9% 6.512% 3 21.1% 31.3% 4.134% 4 62 92 0 48 155 40.3% 24.2% 1.122% 1 47 146 23.6% 23.7% 1.890% 2 47 i00 23,7% 24.3% 1.780% 3 44 55 32.0% 22.2% 1.220% 4 25 44.4% 12.6% 0.871% 5 13 0 27 47 65.8% 13.8% 0.155% 1 27 46 36.5% 13.6% 0.573% 2 27 37 37.0% 13.6% 0.561% 3 25 29 42.2% 12.6% 0.451% 4 20 15 46,3% 10.1% 0.354% 5 10 57.1% 5.1% 0.183% 6 4 0 11 10 71.4% 5.6% 0.049% 1 10 52.4% 10 5.1% 0,122% 2 10 10 50.0% 5.1% 0.122% 3 10 6 50.0% 5.1% O. 122% 4 10 62.5% 4 5.1% o. 073% 5 8 2 71.4% 3.1% O. 049% 6 0 2 75.0% 0.0% 0.024% 0.0% 0.024% IOO 0o I I ,,P Coordination level 2 J" Coordination level 3 aO [OCRerr] X Coordination level 4 r gI Coordination level 5 70 O Coordination level 6 I 30 2O \ \\ \ \ 2O \ 30 40 50 . 60 70 °/o PP.ECISION 80 90 I00