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. FIGURE 4. 805T Index Language Ill. 6. a Exhauattvity of Indexing 3 Search Rule A Document Relevance 1 - 4 Number of Documents in Collection Number of Questions 42 (Subset 2) Number of Relevant Documents 198 Generality Number 23.6 (Controlled terms. Narrower, broader and related terms. 200 (Subset 1) Coordination) Coord- Doeme[OCRerr]ts Recall Precision Fallout ination Retrieved Ratio Ratio Ratio x y z Level Re1, Non-re1. a/a+c a/a+b b/b+d 1 196 5,665 99.0% 3.3% 69.085% 42 42 42 2 187 3,483 94.4% 5.1% 42.465% 42 42 42 3 149 1,609 75.3% 8.5% 19.617% 41 41 41 4 72 527 36.4% 12.0% 6.425% 31 34 34 5 38 140 19.2% 21.3% 1.707% 20 24 24 8 13 31 6.6% 29.5% 0.378% 7 13 13 7 4 7 2.0% 36.4% 0.085% 3 8 8 8 2 3 1.0% 40.0% 0.037% 2 4 4 9 2 1 1.0% 66.7% 0.012% 2 3 3 ioo ao 70 60 ...J ._l <{ 40 30 2O tO I0 \ \ \ i\ \ x:'-[OCRerr] 20 30 "- ) 0")¢" 40 50 60 70 80 °/o PRECISION gO I00 FIGURE 4.805P INDEX LANGUAGE IIL 6. a (Index Language IIL 1. a Broken line)