Presents survey of two groups of databases covering patent literature: patent literature only and general literature that includes patents relevant to subject area of database. Description of databases and comparison tables for patent and general databases (cost, country coverage, years covered, update frequency, file size, and searchable data…

Discusses properties of multiple attribute tree (MAT) and inverted file structures; establishes suitability of MAT data structure for bibliographic files using worst-case performance measures; provides arguments to establish MAT average case superiority; and proposes an efficient adaptation of MAT data structure to exploit special features of MAT…

Presents a preliminary analysis of differences between Disclosure II and Predicasts Annual Reports Abstracts (databases which provide online company information) as available from DIALOG Information Retrieval Services. Sources of online information, duplication of information, company coverage, currency of coverage, accuracy of coverage, and…

Provides exploration into types of numeric databases available (also known as source databases, nonbibliographic databases, data-files, data-banks, fact banks); examines differences and similarities between bibliographic and numeric databases; identifies disciplines that utilize numeric databases; and surveys representative examples in the…

Discusses strengths of abstracting and indexing services (subject coverage, resolution of language problems, systematic indexing) and summarizes sources, countries of origin, languages, total coverage, and indexing of four scientific and technical services--Biosis, Engineering Information, Inspec, Chemical Abstracts Service. Characteristics of…

Presents overview of commercially available databases useful to field of mental health. The availability, costs, coverage, currency, update frequency, and access points are compared for four major files--PsychINFO, National Clearinghouse for Mental Health Information, Social SciSearch, and MEDLINE. Forty-nine references are provided. (EJS)

This bibliography provides citations to 74 articles which compare either single databases across different systems or different databases to each other. All articles included were published after 1976 in Database, Online, Online Review, or the Bulletin of the Medical Library Association. A subject index is provided. (EJS)

Describes a study conducted at the Drexel University Library assessing the ability of the ERIC and Library and Information Science Abstracts (LISA) databases to support the research needs of library science students. A list of search topics and strategies is appended. (Author/LLS)

Describes the methodology and results of a study comparing the overlap of Enviroline, Pollution, and the Environmental Periodicals Bibliography files through searches on acid rain, asbestos and water, diesel, glass recycling, Lake Erie, Concorde, reverse osmosis wastewater treatment cost, and Calspan. Nine tables are provided. (RBF)

Examines some of the primary outlets for IAC (Information Access Company) databases on the Web and evaluates when and why each source might be more appropriate to different situations. Features for DIALOG Web, DataStar Web, DIALOG Select, Dow Jones, and InSite Pro are compared. (Author/LRW)

Discussion of image database systems focuses on semantic queries and shows how an image is abstracted into a hierarchy of entity names and features; how relations are established between entities visible in the image; and how a "fuzzy" matching technique is used to compare semantic queries to image abstractions. (Author/LRW)

Discusses genetic algorithms in information retrieval, especially for relevance feedback, and evaluates the efficacy of a genetic algorithm with various order-based fitness functions for relevance feedback in a test database. Compares results with the Ide dec-hi method, one of the best traditional methods. (Contains 56 references.) (Author/LRW)

The first of four articles describes the move by the European Space Agency to eliminate connect time charges on its online retrieval system. The remaining articles describe the pricing structure of DIALOG, compare the two pricing schemes, and discuss online pricing from the user's point of view. (CLB)

Compares the performance of inverted and signature file organizations in handling incrementally specified Boolean queries to an information retrieval system. The discussion covers the impact of more sophisticated signature file organizations, related problems, and possible future work. (65 references) (CLB)

Considers the appropriateness of using CD-ROM versus online systems. Topics discussed include cost effectiveness; how current the information is; full-text capabilities; a variety of interfaces; graphical user interfaces on CD-ROM; and possibilities for image representations. (LRW)