Describes exploratory experiments in evaluating and improving a thesaurus through studying its effect on retrieval. A formula was developed to measure the conceptual distance between queries and documents encoded as sets of thesaurus terms. Comparison to the performance of people judging conceptual distance shows that the formula accurately…

Reviews aspects of the relationship between machine learning and information retrieval. Highlights include learning programs that extend from knowledge-sparse learning to knowledge-rich learning; the role of the thesaurus; knowledge bases; artificial intelligence; weighting documents; work frequency; and merging classification structures. (78…

Discussion of the information needs of medical professionals and researchers focuses on the architecture of a Web portal designed to integrate advanced searching and indexing algorithms, an automatic thesaurus, and self-organizing map technologies to provide searchers with fine-grained results. Reports results of evaluation of spider algorithms…

Reports an approach to automatic thesaurus construction for Chinese documents. Presents an effective Chinese keyword extraction algorithm. Compared to previous studies, this method speeds up the thesaurus generation process drastically. It also achieves a similar percentage level of term relatedness. Includes three tables and four figures.…

Discusses the problems caused for both users and systems by queries containing negation, and presents an algorithm for transforming Boolean queries with negated terms into queries without negation using a hierarchical thesaurus. A set of user requests submitted to an academic library are also examined to determine the pattern and frequency of use…

Investigates document ranking methods in thesaurus-based Boolean information retrieval systems and proposes a new thesaurus-based ranking algorithm called the Extended Relevance algorithm. Performance comparisons are made between the Extended Relevance algorithm and previous thesaurus-based ranking algorithms. (Contains 20 references.) (LRW)

Discusses the feasibility of building intelligent rule- or weight-based algorithms into general-purpose software for interactive thesaurus navigation. Previous research is surveyed; practical investigations in thesaurus navigation and query enhancement are described; and implications for automatic or intelligent thesaurus navigation are…

Describes a study funded by the Commission of the European Community that applied document retrieval algorithms to the "Excerpta Medica" database using the EMTREE thesaurus. Nonhierarchical relations were added to enrich the thesaurus, and document ranking is discussed in terms of the conceptual distance between the documents and the…

Proposes a model of knowledge-based information retrieval (KBIR) that is based on a hierarchical concept graph (HCG) which shows relationships between index terms and constitutes a hierarchical thesaurus as a knowledge base. Conceptual distance between a query and an object is discussed and the use of Boolean operators is described. (25…

Proposes that topic representations should consist of excerpts from domain thesaurus, generated by spreading activation technique. Algorithm for generating excerpts is outlined and exemplified, and problem of assessing resemblance between two excerpts is discussed. Whether existing thesauri are adequate for this purpose is questioned, and ideas…

Presents an algorithmic approach to addressing the vocabulary problem in scientific information retrieval and information sharing, using the molecular biology domain as an example. A cognitive study and a follow-up document retrieval study were conducted using first a conjoined fly-worm thesaurus and then an actual worm database and the conjoined…

Describes the indexing concept of entry terms, and evaluates existing terms in the Medical Subject Headings by comparing them to the results of an automatic indexer. The results of experimental testing of a strategy for creating entry terms using the algorithms of the automatic indexer are presented. (31 references) (CLB)

The twenty-second in a series, this report describes research in information organization and retrieval conducted by the Department of Computer Science at Cornell University. The report covers work carried out during the period summer 1972 through summer 1974 and is divided into four parts: indexing theory, automatic content analysis, feedback…