Reviews some examples of library searches for both specified documents and specified subjects, and considers the distribution of library resources in relation to varying patterns of searches. (FM)

Analyzes a study of the effect of controlled variations in indexing vocabulary size on retrieval performance, using the Cranfield 200 and 1400 test collections. Sets of variable-length character strings were tested, in an application of the Cluster Hypothesis and in a series of linear associative retrieval experiments. (Author/SW)

Uses an historical analogy with Archimedes' problem concerning the volume of his king's golden crown to illustrate the evaluation problem for document and reference retrieval systems. Various methods that have been developed since 1950 to measure retrieval effectiveness are described, and utility measure formulas are provided. (JD)

Describes a study that computed low performance standards for the group of queries in 13 information retrieval (IR) test collections. Derived from the random graph hypothesis, these standards represent the highest levels of retrieval effectiveness that can be obtained from meaningless clustering structures. (Author/LRW)

Discussion of connectionist views for adaptive clustering in information retrieval focuses on a connectionist clustering technique and activation spreading-based information retrieval model using the interaction information retrieval method. Presents theoretical as well as simulation results as regards computational complexity and includes…

Explains the use of genetic algorithms to combine results from multiple query evaluations to improve relevance in information retrieval. Discusses niching techniques, relevance feedback techniques, and evolution heuristics, and compares retrieval results obtained by both genetic multiple query evaluation and classical single query evaluation…

Describes a study that investigated document retrieval relevance based on document length in an experimental text collection. Topics include term weighting and document ranking, retrieval strategies such as the vector-space cosine match, and a modified technique called the pivoted cosine normalization. (LRW)

Describes a Delphi study conducted to determine factors that affect the process of routing and assigning reference questions received electronically by digital reference services, both to experts within the service and between services. Fifteen factors were determined, by expert consensus, to be important at the conclusion of this study.…

Presents a new method to improve the performance of query processing in a spatial database. Experiments demonstrated that performance of database systems can be improved because both the number of objects accessed and number of objects requiring detailed inspection are much less than those in the previous approach. (AEF)

Describes the architecture and functioning of a system developed specifically for text processing applications--such as information retrieval--that can benefit from structural comparisons between elements of text, such as queries and abstracts. The general ways in which the system performs matches and the ways in which this objective influenced…

Presents a manually constructed knowledge representation aimed at increasing the effectiveness of information retrieval systems. The framework of first order theories is used to analyze the properties of this new structure. The analysis demonstrates that the retrieval function takes term dependencies into account and distinguishes between…

Describes a system based on a probabilistic inference network retrieval model that was used to study the retrieval effectiveness benefits of combining types of document and query information that are found in typical commercial databases and information services. Multiple document representations, multiple index representations, and multiple query…

Discusses the PRECALL, PRR (probability of relevance given retrieval), and EP (expected precision) approaches for dealing with the problem of weak ordering in information retrieval systems. Findings of two experiments comparing evaluation results obtained by PRR and EP are reported. Several mathematical formulas and proofs are included. (20…

Describes an information retrieval methodology based on relevance weighting of search terms in pairs of documents. The vector space model of information retrieval is reviewed, the Bayesian model of text retrieval is discussed, and an automatic implementation of weight estimation using the Medline database is described. (16 references) (LRW)

Presents a logical analysis of the characteristics of indexing and their effects on retrieval. The foundational questions of performance evaluation and the basic quantitative performance measures for binary noninteractive retrieval systems are established. The effects of indexing devices, indexing exhaustivity, specificity, correctness, and…