IRS13 Thesaurus, Phrase and Hierarchy Dictionaries 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. VII-29 Thesaurus-3 Collection Input and Evaluation Thesaurus-3 with Phrases, Type of Thesaurus Measure Dictionary Weight 1.0 Abstract Normed. Recall .9191 .9282 IRE-3 (Thesaurus-2) Normed. Precision .7072 .7252 34 Requests Abstract Normed. Recall .9268 .9326 CThesaurus-3) Normed. Precision .7382 .7529 C[OCRerr]N-l Abstract Normed. Recall .8837 .8791 42 (Thesaurus-3) Normed. Precision .6952 .6873 Requests ADI Text Normed. Recall .8206 .8224 35 (Thesaurus-l) Normed. Precision .6273 .6336 Requests Performance Results Comparing Thesaurus Without and with Phrases for Four Results Using Cosine Numeric on Three Collections, and Normalized Recall and Precision Fig. 19