Discusses the interdependencies between parameter estimation and properties of probabilistic models, such as dependency assumptions, binary vs. nonbinary features, and estimation sample selection. An optimum estimation for binary features applicable to information retrieval is defined, a method for computing this estimation using empirical data is…

Describes a study that supported two hypotheses concerning the use of anaphors in information retrieval: first, that anaphors tend to refer to integral concepts rather than peripheral concepts; second, that various term weighting schemes are affected differently by anaphoric resolution. The implications for the use of anaphoric resolution for…

Discussion of a new method of index term dictionary compression in an inverted-file-oriented database highlights a technique of word coding, which generates short fixed-length codes obtained from the index terms themselves by analysis of monogram and bigram statistical distributions. Substantial savings in communication channel utilization are…

Summarizes the experimental evidence that indicates that text indexing systems based on the assignment of appropriately weighted single terms produce retrieval results superior to those obtained with more elaborate text representations, and provides baseline single term indexing models with which more elaborate content analysis procedures can be…

Describes study that compared terminology indexing and citation indexing to determine the similarity of documents retrieved. Information science articles from 1971 to 1983 in three journals were studied for term co-occurrences. The distinction between relevant and pertinent documents is discussed, and further research topics are suggested. (LRW)

Discussion of online bibliographic database searches focuses on a software system, SORT-AID/SABRE, that ranks retrieved citations in terms of relevance. Results of a comprehensive user evaluation of the relevance ranking procedure to determine its effectiveness are presented, and implications for future work are suggested. (10 references) (LRW)