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. - 144 - 10E 8O ½ % 7( R E C A 6c L L 0.001 O. O1 0.1 % FALLOUT 1.0 10 100 FIGURE 4.607P HECALL-FALLOUT PLOT SHOWING EFFECT OF CHANGES IN I[OCRerr]ELEVANCE ON -I2 QUESTIONS WITH 1400 DOCUMENT COLLECTION, INDEX LANGUAGE 1.6.a.