CRANV2 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. - 38 - Coordination Level Documents Retrieved Rel (a) Non-Rel (b) Recall Ratio a/a+ C Precision Ratio a/a-[OCRerr] b 1 97 2,674 69.3% 3.5% 2 77 788 55.0% 8.9% 3 56 220 40. 0% 20. 3% 4 37 30 26.4% 55.2% 5 33 17 23.6% 66.0% Relevant documents (a + e) = 140 Generality number 5 1oo 9o 8o 7o 6o 5O 40 3O I0 0 9 % \ ,,,,, I0 20 30 40 50 60 70 80 90 I00 *1. PRECISION FIGURE 3.4TP TABLE AND PLOT OF TEST RESULTS FOR 20 QUESTIONS SHOWING RECALL AND PRECISION RATIOS FOR SEARCH Y (BROKEN LINE) (SEARCH X CONTINUOUS LINE)