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Experimental evidence suggests that enhancing the subject content of OPAC records can improve retrieval performance. This is based on the use of natural language index terms derived from the table of contents and back‐of‐the‐book index of documents. The research reported here investigates the alternative approach of translating these natural language terms into controlled vocabulary. Subject queries were collected by interview at the catalogue, and indexing of the queries demonstrated the impressive ability of PRECIS, and to a lesser extent LCSH, to represent users' information needs. DDC performed poorly in this respect. The assumption was made that an index language adequately specific to represent users' queries should be adequate to represent document contents. Searches were carried out on three test databases, and both natural language and PRECIS enhancement of MARC records increased the number of relevant documents found, with PRECIS showing the better performance. However, with weak stemming the advantage of PRECIS was lost. Consideration must also be given to the potential advantages of controlled vocabulary, over and above basic retrieval performance measures.

What is Controlled English? Its use and application. The rules of Controlled English and their meaning. Max — a Controlled English tool. The Controlled English dictionaries. Implementation of Controlled English within Bull. Guidelines for implementing a Controlled Language system with or without Machine Translation.

A number of techniques have been studied for the automatic assignment of controlled subject headings and classifications from free indexing. These techniques involve the automatic manipulation and truncation of the free‐index phrases assigned to a document and the use of a manually‐constructed thesaurus and automatically‐generated dictionaries together with statistical ranking and weighting methods. These are based on the use of a statistically‐generated ‘adhesion coefficient’ which reflects the degree of association between the free‐indexing terms, the controlled subject headings, and the classifications. By the analysis of a large sample of manually‐indexed documents the system generates dictionaries of free‐language and controlled‐language terms together with their associated classifications and adhesion coefficients. Having learnt from the manually‐indexed documents the system uses these dictionaries in the subsequent automatic classification procedure. The accuracy and cost‐effectiveness of the automatically‐assigned subject headings and classifications has been compared with that of the manual system. The results were encouraging and the costs comparable to those of a manual system.

Reports a laboratory comparison of the effectiveness and efficiency of five index languages in the subject area of library and information science; three post‐co‐ordinate languages, Compressed Term, Uncontrolled, and Hierarchically Structured, and two pre‐co‐ordinate ones, Hierarchically Structured and Relational Indexing. Eight test comparisons were made, and factors studied were index language specificity and linkage, indexing specificity and exhaustivity, method of co‐ordination, the precision devices of partitioning and relational operators, and the provision of context in the search file. Full details of the test and retrieval results are presented.

The use of an uncontrolled vocabulary or natural language as it is sometimes called, has long been the traditional method of assigning a title to a file.

This article reviews the state of the art in automatic indexing, that is, automatic techniques for analysing and characterising documents, for manipulating their descriptions in searching, and for generating the index language used for these purposes. It concentrates on the literature from 1968 to 1973. Section I defines the topic and its context. Sections II and III consider work in syntax and semantics respectively in detail. Section IV comments on ‘indirect’ indexing. Section V briefly surveys operating mechanized systems. In Section VI major experiments in automatic indexing are reviewed, and Section VII attempts an overall conclusion on the current state of automatic indexing techniques.

Reviews the approaches to the organisation of knowledge in Web‐based environments. The control and structure helps searchers to locate information and services, but only provided that searchers understand and relate to the terms and information structure designed into the system. The other alternative is for the searcher to specify the topic of their search through the use of keywords. These keywords are in the natural language of the searcher, which may or not be coincident with the natural language of the Web sites being searched by the search engine. In order to negotiate the variability of natural language the searcher needs to learn to use more advanced search features such as Boolean searching, nesting and truncation. The knowledge organisation issues associated with access to and retrieval from large databases, such as those that are searched across the Web, are significant and need careful and specialist attention.

The importance of language management in multinational companies has never been greater than today. Multinationals are becoming ever more conscious of the importance of global coordination as a source of competitive advantage, and language remains the ultimate barrier to aspirations of international harmonisation. The article reviews the solutions open to multinational companies in term of language management. Before that, however, it discusses the aforementioned trend to globalisation outlines the dimensions of the language barrier and illustrates its consequences.

Many retrieval experiments have been based on inadequate test collections, and current research is hampered by the lack of proper collections. This short review does not attempt a fully documented survey of all the collections used in the past decade: hopefully representative examples have been studied to throw light on the requirements test collections should meet, to show how past collections have been defective, and to suggest guidelines for a future ‘ideal’ test collection. The specifications for this collection can be taken as an indirect comment on our present state of knowledge of major retrieval system variables, and experience in conducting experiments.

Providing effective subject access to OPACs is a major problem area and this article considers the relative merits of providing enhanced content indexing of document records with natural language or controlled vocabulary. The retrieval performance of a particular approach is not the only factor to be taken into consideration and the need for multilingual subject access to OPAC records is discussed.