The Swets model of information retrieval as a decision theory model is reviewed. (Author)

A procedure for adjusting queries to retrieve more documents for a user by automatically selecting and broadening the descriptors from relevant documents is described. Although more computing is required, recall and precision are superior to traditional searching. (KP)

A comparative evaluation of results in terms of recall and precision from queries submitted to systems with automatic and manual subject indexing. Differences were attributed to query formulation. The effectiveness of automatic indexing was found equivalent to manual indexing. (Author/KP)

Briefly surveys the numerous applications of fuzzy set theory on data representation and information retrieval. The importance of fuzzy set theory with respect to information systems is illustrated with a bibliography of 86 papers that describe data systems that are somehow "fuzzy." (Author/EM)

A test was carried out to investigate the assumption that there is a significant level of redundancy between documents. The conclusions were that notional overlap exists, but there appear to be very few cases of extreme redundancy, and at the document level, there is little possibility of practical application. (Author)

The parameters of effectiveness evaluation of information systems put forward in this paper take account of the fact that both evaluation of the relevance and evaluation of the pertinence of documents are of a continuous character. (Author)

Some of the factors that must inevitably affect the assessment of printed indexes are discussed, together with the observation of two unexpected phenomena, namely an apparent relationship between precision and searching effort, and relationships between generality and both recall and fallout. (4 references) (Author)

The SMART system is used for the analysis, search and retrieval of news stories appearing in Time'' magazine. A comparison is made between the automatic text processing methods incorporated into the SMART system and a manual search using the classified index to Time.'' (14 references) (Author)

An evaluation of the Epilepsy Abstracts Retrieval System (EARS) was performed. Searches were conducted on the on-line system and evaluated in terms of recall, precision, and general user satisfaction. A detailed analysis of factors affecting the success and failure of the on-line searches was carried out. (4 references) (Author/SJ)

An investigation was made into the relative performance of the four major Chemical Abstracts Service magnetic tape data-bases. The overall retrieval efficiency of profiles searched against data-bases containing titles only, titles-plus-keywords, and titles-plus-digests, was calculated and these results are presented. (5 references) (Author/NH)

Three experiments were made by a flexible machine search system to test the retrieval efficiency of searching free text and keywords. Results based upon relevance judgements of users indicate that titles and abstracts are good index material which can be used for machine searching without human indexing. (Author/SJ)

Reviews literature relating to Bradford's Law of Scatter, which groups journals and articles to identify number of periodicals relevant to particular subject, and notes the gap between theoretical and empirical studies, i.e., no relationship has been found between variables which characterize empirical situations and theoretical models. Thirteen…

Reports the results of experiments using colon classification for the analysis, representation, and retrieval of primary information from the full text of documents. Recall, precision, and search length measures indicate colon classification did not perform significantly better than Boolean or simple word occurrence systems. Thirteen references…

Isolates a number of criteria that should be met by any Boolean system generalized to have a weighting capability, and proves that the one weighting rule satisfying these conditions satisfies most of the other properties associated with Boolean algebra as well. Thirteen references are listed. (FM)

Replies to Stephen E. Robinson's article on the role of fuzzy set theory in information science (Journal of the American Society for Information Science; v29 n6 Nov 1978), particularly with regard to Robinson's discussions of uncertainty, min/max connectives, and relevance. (FM)