Compares the differences in coverage and utility of three substructure databases--Chemical Abstracts, Index Chemicus, and Chemical Information System's Nomenclature Search System. The differences between Chemical Abstracts with two different vendors--STN International and Questel--are described and a summary guide for choosing between databases is…

Reviews the advantages and disadvantages of different types of term combination using the positional logic capability of online information retrieval systems and describes a study in which searches for material on "microwave integrated circuits" were conducted in order to find the most economical way of generating the most relevant…

A standard online search strategy involving use of acronyms is evolved and searches are performed over wide range of databases. Advantage gained by use of acronyms is measured with respect to free and controlled terms, and percentages of extra documents retrieved are given. Four references and sample searches are included. (EJS)

In order to compare effects of input processing on information retrieval in three databases, 25 articles from a specific journal were examined. Tables and Venn diagrams show retrieval results from different manual and computer searches. The relation between document surrogates and subject matter of the documents is discussed. (SW)

Identifies characteristics of the experienced online searcher and discusses the results of three searches carried out by a variety of searchers in widely differing subject fields--presence of arsenic in coal, problems of working alone in laboratory or work area, and spectral sensitivity of the insect eye. (8 references) (EJS)

Examines the changing role of controlled vocabulary in the postcoordinate online search, particularly its current role in the formulation of online search strategies. Effects of controlled vocabulary searching on precision and recall and examples of concept "hedges" from the "Thesaurus of ERIC Descriptors" are discussed. Nine…

Explores the effects on relevance concerns in traditional online search strategies caused by ranking retrieved documents. Two extreme examples are presented to illustrate the impact of ranking; advantages and limitations of ranking are discussed. (SW)

A comparative evaluation of two computerized reference retrieval systems, INSTRUCT (a statistically-based system) and PLEXUS (a knowledge-based system) examined their retrieval effectiveness for a set of 19 queries and 512 documents on gardening. Best results were obtained by using terms suggested by PLEXUS as the basis for an INSTRUCT search. (36…

Evaluates overlapping coverage of 21 scientific databases used in 10 online pesticide searches in an attempt to identify minimum number of databases needed to generate 90 percent of unique, relevant citations for given search. Comparison of searches combined under given pesticide usage (herbicide, fungicide, insecticide) is discussed. Nine…

Discussion of online searching in the humanities focuses on a comparison of the retrieval from two databases which cover philosophical materials, Philosopher's Index and FRANCIS. Retrieval performance measures are described, including precision and number of relevant records, and the results are discussed. The article concludes with a…

Explains why Internet groups are a good medium for retrieving and exchanging information. An example of the use of netgroups to obtain information on the Gulf War of 1990-91 is given; the benefits of the informal nature of netgroups are discussed; and a mediated discussion group, Humanist, is described. (LRW)

Analytical methods for facilitating comparison of multiple sets during online searching are illustrated by description of specific searching methods that eliminate duplicate citations and a factoring procedure based on syntactic relationships that establishes ranked sets. Searches executed in National Center for Mental Health database on…

Argues that information retrieval based on semantic representation is not helpful for those searchers who do not have well-defined ideas of the target document type. Presents an alternative, complementary method for indexing and document retrieval based on attributes of argumentation, a characteristic of articles advancing a claim. (52 references)…

Describes various modifications of query formulations, or moves, made by experienced online searchers to improve search results. Operational moves that modify query formulation while keeping meaning of query components unchanged and conceptual moves that change meaning of query components are described; all moves are then related to search tactics…

Reviews 12 different methods of information retrieval for the reduction of a large set by removal of irrelevant or unwanted elements, including logic revision (use of "and" and "not" logic, classification codes, limit commands, field restriction), concept revision, and terminology revision. Examples for each option are given.…