Discusses Noetica, a tool that uses a semantic network for structuring knowledge about concepts and the relationships between them. It differs from typical information systems in that the knowledge it represents is abstract, highly connected, and includes metaknowledge. Class hierarchy, visualization, and query tools are also discussed.…

Shows that in advanced information-retrieval applications capabilities for data aggregation, transitive computation and non-first normal-form relational computation are often necessary at the same time. Topics include complex objects; advanced data models; query languages; query formulation; knowledge representation; and query-language syntax.…

Presents a faster method for determining hierarchical relationships in information retrieval by using trie structures instead of a linear storage of a concept code. Highlights include case structures, a knowledge representation for natural-language understanding with semantic constraints; a compression algorithm of tries; and evaluation.…

Discusses automatic document classification and document retrieval systems and presents a strategy for building a morphological machine dictionary of English that infers meaning of derivations by considering morphological affixes and their semantic classification. Proposes a method for selecting compound field association terms from a large pool…

Introduces a framework for comparing and evaluating knowledge representation schemes based on the requirements for "good" representation discussed in extant literature. Comparative analysis and evaluation of four popular knowledge representation schemes--Logic, Production Rules, Semantic Nets and Frames--are discussed in support of validity and…

Examines four working steps from an empirical model where an expert abstractor discovers what a paper is about and drafts a topic sentence; a simulation system is developed using this model. Discusses knowledge processing activities of professional summarizing. Results indicate that a small simulation model of professional summarizing is feasible.…

Introduces characteristics of the sublanguage found in diagnostic messages about automotive equipment failures and discusses a system for minimizing jargon. Proposes using general knowledge sources and evaluates levels of communication accuracy, robustness and efficiency. (AEF)

The Latent Semantic Indexing and MatchPlus systems examine similar contexts in which words appear and create representational models that capture the similarity of meaning of terms and then use the representation for retrieval. Text Retrieval Conference experiments using these systems demonstrate the computational feasibility of using…

Reports on two studies in the second Text Retrieval Conference (TREC-2) program that investigated the effect on retrieval performance of combination of multiple representations of TREC topics. Six methods of query combinations and the combination of the same queries on different databases are examined. Results show that combining evidence from…

Describes and evaluates a system that selects key information from an event database by reasoning about event frequencies, frequencies of relations between events, and domain-specific importance measures. The system aggregates similar information and plans a summary tailored to a stereotypical user. (AEF)

Demonstrates that if the similarity function of a retrieval system leads to a (pseudo-) metric, the retrieval, similarity and Everett-Cater metric topology coincide and are different from the discrete topology; this is the case if documents are represented by lists, using the Jaccard similarity measure. The corresponding metric is the…

A consultation quality control model (CQCM) developed for an expert system (ES) integrated both ES performance measures and end-user judgment values. Simple decision theory concepts were used to design the CQCM. Results show end users belong to different categories characterized by utility functions and the weights they assign to ES consultation…

Discusses similarities and differences between knowledge acquisition in expert systems and requirement acquisition in others kinds of information systems (particularly decision support systems). Examines role-limiting methods for automated knowledge acquisition and their integration from the problem-solving perspective. Suggests a feasibility…

Increasing information retrieval performance using phrases and part-of-speech (POS) information is one example of a type of decision-making performance that is improved when using this linguistic information. The relative effectiveness of using multi-term phrases as opposed to individual terms is shown, as well as the relative worth of POS tagged…

Reports on the design of an automated query system to help pharmacologists access the Derwent Drug File (DDF). Topics include knowledge types; knowledge representation; role of the search intermediary; vocabulary selection, thesaurus, and user input in natural language; browsing; evaluation methods; and search statement generation for the World…