Discusses the problems associated with using connect time as the basis of user fees for searching numeric online databases, and proposes a methodology for user charge estimation based on query formulation and results. (87 references) (CLB)

Using a newspaper article database, this study analyzed the effects of ellipsis and anaphor resolution on proximity searching in a full-text database; 154 keyword pairs in different categories were created. Findings indicate that some resolution method might be developed only for proper name phrases to support keyword-based full-text information…

Provides an overview of the development and use of numeric databases, and of the evolution of user charging methods for all online information retrieval systems. The need to provide database users with advance estimates of charges is discussed, and a methodology for charge estimation is presented. (87 references) (CLB)

Describes a method for advance estimation of user charges for queries in relational data model-based numeric databases when charges are based on data retrieved. Use of this approach is demonstrated by sample queries to an imaginary marketing database. The principles and methods of this approach and its relevance are discussed. (MBR)

Develops an approach for advance estimation of user charges based on information actually retrieved by searching numeric databases, and defines a method for query cardinality estimation. Based on the relational data model, which uses relational algebra, this method uses formal file descriptions to describe the database files. (LRW)

Discusses a user interface that simplifies NF Squared (non-first-normal-form) relational query formulation in which query specification remains compact and straightforward. This interface allows for nesting and general hierarchical structures and restructuring which provides for more effective retrieval and query formulation. (Author/JKP)

The resolution power of a key is its ability, in the context of other keys for a given request, to increase query performance. This article studies the statistical properties of search keys, methods of characterizing the resolution power of keys automatically, and effects keys of varying resolution power have on retrieval effectiveness. (AEF)