IRS13 Test Environment 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. FiRST RELEVANT SECOND RELEVANT LAST RELEV ECTION AND[OCRerr]Number of CTIONARY I Average % of Average % of Average Documents Requests Rank Collection Rank Collection Rank Col [OCRerr]stracts, Stem 780 14.[OCRerr] 0.6% 11.6 1.5% 334.0 kbstracts, Stem 200 [OCRerr]2 7.8 3.9% 13.0 6.5% 72.0 I I 1 I [OCRerr]bstracts, Stem 82 35 8.1 9.9% 15.7 19.2% 39.2 1 I I I Comparisons of the Three Collections using Average Rank positions of the First, Second and Last Relevant Documents, Stem Dictionary Fig. 23