Thesaurus-assisted search term selection and query expansion: a review of user-centred studies

This paper provides a review of the literature related to the application of domain-specific thesauri in the search and retrieval process. Focusing on studies which adopt a user-centred approach, the review presents a survey of the methodologies and results from empirical studies undertaken on the use of thesauri as sources of term selection for query formulation and expansion during the search process. It summaries the ways in which domain-specific thesauri from different disciplines have been used by various types of users and how these tools aid users in the selection of search terms. The review consists of two main sections covering, firstly studies on thesaurus-aided search term selection and secondly those dealing with query expansion using thesauri. Both sections are illustrated with case studies that have adopted a user-centred approach

CC-interop : COPAC/Clumps Continuing Technical Cooperation. Final Project Report

As far as is known, CC-interop was the first project of its kind anywhere in the world and still is. Its basic aim was to test the feasibility of cross-searching between physical and virtual union catalogues, using COPAC and the three functioning "clumps" or virtual union catalogues (CAIRNS, InforM25, and RIDING), all funded or part-funded by JISC in recent years. The key issues investigated were technical interoperability of catalogues, use of collection level descriptions to search union catalogues dynamically, quality of standards in cataloguing and indexing practices, and usability of union catalogues for real users. The conclusions of the project were expected to, and indeed do, contribute to the development of the JISC Information Environment and to the ongoing debate as to the feasibility and desirability of creating a national UK catalogue. They also inhabit the territory of collection level descriptions (CLDs) and the wider services of JISC's Information Environment Services Registry (IESR). The results of this project will also have applicability for the common information environment, particularly through the landscaping work done via SCONE/CAIRNS. This work is relevant not just to HE and not just to digital materials, but encompasses other sectors and domains and caters for print resources as well. Key findings are thematically grouped as follows: System performance when inter-linking COPAC and the Z39.50 clumps. The various individual Z39.50 configurations permit technical interoperability relatively easily but only limited semantic interoperability is possible. Disparate cataloguing and indexing practices are an impairment to semantic interoperability, not just for catalogues but also for CLDs and descriptions of services (like those constituting JISC's IESR). Creating dynamic landscaping through CLDs: routines can be written to allow collection description databases to be output in formats that other UK users of CLDs, including developers of the JISC information environment. Searching a distributed (virtual) catalogue or clump via Z39.50: use of Z39.50 to Z39.50 middleware permits a distributed catalogue to be searched via Z39.50 from such disparate user services as another virtual union catalogue or clump, a physical union catalogue like COPAC, an individual Z client and other IE services. The breakthrough in this Z39.50 to Z39.50 conundrum came with the discovery that the JISC-funded JAFER software (a result of the 5/99 programme) meets many of the requirements and can be used by the current clumps services. It is technically possible for the user to select all or a sub-set of available end destination Z39.50 servers (we call this "landscaping") within this middleware. Comparing results processing between COPAC and clumps. Most distributed services (clumps) do not bring back complete results sets from associated Z servers (in order to save time for users). COPAC on-the-fly routines could feasibly be applied to the clumps services. An automated search set up to repeat its query of 17 catalogues in a clump (InforM25) hourly over nearly 3 months returned surprisingly good results; for example, over 90% of responses were received in less than one second, and no servers showed slower response times in periods of traditionally heavy OPAC use (mid-morning to early evening). User behaviour when cross-searching catalogues: the importance to users of a number of on-screen features, including the ability to refine a search and clear indication that a search is processing. The importance to users of information about the availability of an item as well as the holdings data. The impact of search tools such as Google and Amazon on user behaviour and the expectations of more information than is normally available from a library catalogue. The distrust of some librarians interviewed of the data sources in virtual union catalogues, thinking that there was not true interoperability

Bibliographic and Technical Problems in Implementing a National Library Network

published or submitted for publicatio

The NASA Astrophysics Data System: Architecture

The powerful discovery capabilities available in the ADS bibliographic services are possible thanks to the design of a flexible search and retrieval system based on a relational database model. Bibliographic records are stored as a corpus of structured documents containing fielded data and metadata, while discipline-specific knowledge is segregated in a set of files independent of the bibliographic data itself. The creation and management of links to both internal and external resources associated with each bibliography in the database is made possible by representing them as a set of document properties and their attributes. To improve global access to the ADS data holdings, a number of mirror sites have been created by cloning the database contents and software on a variety of hardware and software platforms. The procedures used to create and manage the database and its mirrors have been written as a set of scripts that can be run in either an interactive or unsupervised fashion. The ADS can be accessed at http://adswww.harvard.eduComment: 25 pages, 8 figures, 3 table

An investigation to study the feasibility of on-line bibliographic information retrieval system using an APP

This thesis was submitted for the degree of Doctor of Philosophy and was awarded by Brunel University.This thesis reports an investigation on the feasibility study of a searching mechanism using an APP suitable for an on-line bibliographic retrieval, operation, especially for retrospective searches. From the study of the searching methods used in the conventional systems it is seen that elaborate file- and data- structures are introduced to improve the response time of the system. These consequently lead to software and hardware redundancies. To mask these complexities of the system an expensive computer with higher capabilities and more powerful instruction set is commonly used. Thus the service of the systen becomes cost-ineffective. On the other hand the primitive operations of a searching mechanism, such as, association, domain selection, intersection and unions, are the intrinsic features of an associative parallel processor. Therefore it is important to establish the feasibility of an APP as a cost-effective searching mechanise. In this thesis a searching mechanism using an 'ON-THE-FLY' searching technique has been proposed. The parallel search unit uses a Byte-oriented VRL-APP for efficient character string processing. At the time of undertaking this work the specification for neither the retrieval systems nor the BO-VRL APP's were well established; hence a two-phase investigation was originated. In the Phase I of the work a bottom up approach was adopted to derive a formal and precise specification for the BO-VRL-APP. During the Phase II of the work a top-down approach was opted for the implementation of the searching mechanism. An experimental research vehicle has been developed to establish the feasibility of an APP as a cost-effective searching mechanism. Although rigorous proof of the feasibility has not been obtained, the thesis establishes that the APP is well suited for on-line bibligraphic information retrieval operations where substring searches including boolean selection and threshold weights are efficiently supported

Capitalizing on Information Organization and Information Visualization for a New-Generation Catalogue

Subject searching is difficult with traditional text-based online public access library catalogues (OPACs), and the next-generation discovery layers are keyword searching and result filtering tools that offer little support for subject browsing. Next-generation OPACs ignore the rich network of relations offered by controlled subject vocabulary, which can facilitate subject browsing. A new generation of OPACs could leverage existing information-organization investments and offer online searchers a novel browsing and searching environment. This is a case study of the design and development of a virtual reality subject browsing and information retrieval tool. The functional prototype shows that the Library of Congress subject headings (LCSH) can be shaped into a useful and usable tree structure serving as a visual metaphor that contains a real world collection from the domain of science and engineering. Formative tests show that users can effectively browse the LCSH tree and carve it up based on their keyword search queries. This study uses a complex information-organization structure as a defining characteristic of an OPAC that goes beyond the standard keyword search model, toward the cutting edge of online search tools.published or submitted for publicatio