ISR10 Table of Contents table of contents Joseph John Rocchio Harvard University Gerard Salton Use, reproduction, or publication, in whole or in part, is permitted for any purpose of the United States Government. [OCRerr]ABLE OF COi[OCRerr]E[OCRerr]S (continued) CKAP[OCRerr]RR 3 SEARCII REQUES[OCRerr] FO[OCRerr]LA[OCRerr]ION[OCRerr] . 1. [OCRerr] . 2. Request For[OCRerr]nula'tion . 3. Request Optimization . 4. Relevance Feed[OCRerr]ack . 5. The Case 0£ [OCRerr]0 Relevant Documents 6. Lx' perimental Results . . A. Some Sample Searoli Requests B. Average Results and Successive Iterations C. Convergence * . 3-1 * . . 3-1 3-3 * . . 3-5 3-11 3-20 3-21 3-21 3-32 3-42 CHAP[OCRerr]R 4 [OCRerr] QUERY-DOCU[OCRerr][OCRerr]E[OCRerr] [OCRerr]TCRING [OCRerr]C[OCRerr]IO[OCRerr] 4-1 1. The Comparison 0£ Structured Operands 4-1 2. Storage Organization 4-7 3. Automatic Document Classi£ication 4-12 4. Classi£ication and Netric Searching 4-16 5. A Heuristic Classi£ication Algorithm 4-19 A. Basic Concepts 4-19 B. Description 0£ -[OCRerr]he Classi£ication Algorithm 4-20 6. Ebcperimental Results 4-36 viii