IRS13 Scientific Report No. IRS-13 Information Storage and Retrieval An Analysis of the Documentation Requests 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. X-21 SPECIFIC, GENERAL, EVALUATION LONG Aś[OCRerr] SHORT AND DICTIONARY MEASURE LOW F[OCRerr]E[OCRerr]UENCY, HIGH FREQUENCY, 9 REQUESTS 10 REQUESTS Stem Normed. Recall .8309 .5812 Normede Precision .6085 .[OCRerr]O72 I Thesaurusi Normed. Recall .8617 .72147 ( Normede Precision .6702 .5870 Performance Results Comparing Two Subsets of the Requests Having the Expected Correlations Between Length, Generality and Average Concept Frequency Figure 10.