IRS13 Word-Word Associations in Document Retrieval Systems chapter M. E. Lesk Harvard University Gerard Salton Use, reproduction, or publication, in whole or in part, is permitted for any purpose of the United States Government. 0 (½3 Harris 3 Thesaurus Stem Concon (Frequency Thesaurus (Ho rris) 0 D 0 Stem Concon (Frequency Thesaurus Stem Concon (F 6-100, K=0.45) 6-100, KuO.45) 6-100, K:0 PRECISION PRECISION PRECISION I.c 0.E - O.E- 0.4 - 0.2- I.c - 0 I a a a . RECALL 0 0.2 0.4 0.6 0-8 1.0 IC - 0.8 - o\ O.E 0.E OA 0.4- 0.2- I I a . RECALL 0 0.2 0.4 0.6 I a a a 0.8 1.0 0 0.2 0.4 0.6 0.8 IRE-3, 34 Requests Cranfield-l, Abstrocts,42 Requests ADI, Full Text, 35 RE Comparison of Thesaurus Performance with Statistical Word - Word Association (Stem Concon). Fig. iS