Presents new methods for compressing bit matrices in large information retrieval systems which exploit possible correlations between rows of words and columns of documents. Three encoding methods are tested and compared--Shannon-Fano, arithmetic, and Huffman--and an appendix discusses binomial coefficients. (20 references) (LRW)

Explores what might be the optimal query expansion (QE) processing method with semantically coded thesauri. Examines whether QE via semantically coded thesauri terminology is more effective in the "automatic" or "interactive" processing environment. Results revealed that synonyms and partial synonyms and narrower terms are…

Uses Kintsch's proposition-based construction-integration theory of discourse comprehension to detail the user coding operations that occur in each of the three subsystems (Perception, Comprehension, Application) in which users process an information retrieval systems (IRS) message. Describes an IRS device made up of two separate parts that enable…