IRS13 Scientific Report No. IRS-13 Information Storage and Retrieval Evaluation Parameters chapter E. M. Keen Harvard University Gerard Salton Use, reproduction, or publication, in whole or in part, is permitted for any purpose of the United States Government. 11-32 xh u Number of Requests Entering Average Precision 1.0 0.8 0.6 0.4 0.2 ¼~ \31 [OCRerr]4l [OCRerr]4l [OCRerr]4I [OCRerr] 42 x ````` Recoil 0 0.2 0.4 0.6 0.8 1.0 Cr an-i, A[OCRerr]stract S, Stem, "[OCRerr]uas i -Cranfield'1 Cut-off, Macro Evaluation of [OCRerr]2 Requests. Illustration of First )4ethod of Averaging Where Individual Requests have Var[OCRerr]g Amounts of Relevant Documents Fig. 18