Examines various kinds of uncertainty in information science. The notion of ambiguity is defined and contrasted with the more familiar notions of randomness and vagueness. Functional forms resistant to ambiguity are defined, and it is shown how to incorporate a random component, that is itself also resistant to ambiguity, into a resilient, but…

Applies a prefix trie index, or trie hashing, to the problem of providing fast search times, fast load times, and fast update properties in a bibliographic or full-text retrieval system with inverted files. Statistics are given for a test database consisting of an online catalog at the University of Western Ontario. (Author/LRW)

Describes the Archive Retrieval and Analysis System (ARRAS), which provides rapid access to textual data and fast, flexible, open-ended analysis of individual texts; explains why the system should be viewed as a new kind of working environment; and suggests that such systems may influence users' intellectual point of view. (MBR)

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…

Describes a study that analyzed transaction logs of users of Excite, an Internet search service. Highlights include data on sessions (changes in queries, number of pages viewed, and relevance feedback), queries (number of search terms and the use of logic and modifiers), and terms (rank/frequency distribution); user characteristics; and failure…

Zipfian laws for frequency distributions of word pairs and longer phrases are derived from text sample analysis. From crossing of Zipfian curves, it is deduced that number of multi-word phrases that occur frequently in text is surprisingly small, of same order of magnitude as number of individual word-types. (8 references) (EJS)