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. Request Ranks of Relevant A B -- C 2,5,6 3,14 23 recision Precision 1.0 1.0 - ½ 0.8 - 0.6 - 0.6 - Third Extrapolation Method, 1.0 [OCRerr] precision at 0.0 recall. [OCRerr] Fifth Extrapolation Method, using o precision of first relevant. 0 ¼ 0.2 A >II[OCRerr] I I 0 0.2 0.4 0.6 0.8 1.0 a) Three Individual Requests using 1.0 precision at 0.0 recall Recoil 0.4 - 0.2 - I [OCRerr] Recall 0 0.2 0.4 0.6 0.8 1.0 b) Comparison of Two Extrapolation Methoc using Averaged Results Cran-l, Abstracts, Stem, "[OCRerr]uasi-Cranfield' Extrapolation Method Cut-off, Macro Evaluation of 42 Request[OCRerr] Comparisons of Extrapolation Methods Three and Five Fig. 23