Describes the changes scientific abstracting and indexing services are making to develop new production systems for a marketplace which is influenced by the information superhighway and the demand for information in an electronic format. Descriptions are included of computer system and data input changes implemented by several database producers…

Provides an overview of the Canadian business environment and online sources of business information. The databases described cover the following areas: directories, financial information, stock quotes, investment reports, industrial and economic information, magazines, newspapers, wire services, biographical information, and government…

Describes three groups of databases sponsored by the European Communities Commission: Eurobases, a textual database of the contents of the "Official Journal" of the European Community; the European Community Host Organization (ECHO) databases, which offer multilingual information about Europe; and statistical databases. Information on…

Discusses the growth in nonbibliographic online databases and machine-readable data files (MRDF) that are accessed offline, and considers how libraries need to respond to the changing needs and expectations of researchers. Textual and numeric databases are described, and three possible levels of library service are outlined. (13 references) (LRW)

University Microfilms International (UMI) collects, creates, and preserves information from the fields of business, education, engineering, social science, and the popular media and makes it available in print and microform, as well as online, on CD-ROM, and on magnetic tape. The company also develops integrated information delivery systems. (KRN)

Provides an overview of factual data banks and full text files available on optical data disks. Each entry in the directory includes the name of the data bank or file; producer; distributor; frequency of updates; period covered; subscription price; and a summary of the contents. Addresses of producers and distributors are provided. (CLB)

In the first of three articles, the producer of Energyline, Energynet, and Tele/Scope recalls the development of the databases and database business strategies. The second describes the development of biomedical online databases, and the third discusses future developments, including full text databases, database producers as online host, and…

Examines problems encountered when setting up a hypertext link, called an identity link, for moving between bibliographic and full text databases. MEDLINE and CCML (Comprehensive Core Medical Library) are used as examples, BRS/SEARCH text retrieval software is explained, and problems with syntax are discussed. (two references) (LRW)

Describes a hierarchical text database model and defines an algebra based on concordance lists. The algebra is presented as a theoretical model to define both a conceptual schema for the database and search protocols for database implementation. Several retrieval examples are included. (19 references) (MES)

Describes the method used by the American Chemical Society to keyboard its primary journals directly into a publishing database, which is then used to produce printed journals and create an online full text file. The use of a generalized mark-up format to convert journals not keyboarded in such a manner is suggested. (four references) (CLB)

Describes an approximate document ranking process that uses a compact array of in-memory, low-precision approximations for document length. Combined with another rule for reducing the memory required by partial similarity accumulators, the approximation heuristic allows the ranking of large document collections using less than one byte of memory…

Presents two groups of text encoding problems encountered by the Brown University Women Writers Project while using Standard Generalized Markup Language (SGML) to create a database of book transcriptions: dual emendation and correction, and multiple hierarchies. Offers several possible approaches to these encoding problems and analyzes the issues…

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)

Reviews selected research on the performance of bibliographic and full-text databases. A mathematical model for clarification of the relationship between user behavior and the performance measures of recall and precision is presented. (five references) (MES)

Describes a new signature file method, called the multiorganizational scheme, for accessing information from large databases containing both formatted and free-text data. Implementation issues are discussed, and computational results based on a mathematical model are presented, as well as results using a library database. (43 references) (MES)