PACE: A Browsable Graphical Interface
Jamshid Beheshti · Information Technology and Libraries · 1996
PACE (Public Access Catalogue Extension) is an alternative interface designed to enhance online catalogs. PACE simulates images of books and library shelves to help users browse through the catalog. PACE was tested in a college library against a text-based, online public access catalog (Best-Seller) in a real operational environment. The show that a simple browsable retrieval interface performed as well as a second-generation OPAC in terms of retrieval speed and search success. The overwhelming majority of students, however, preferred the browsing capability of PACE through the familiar metaphor of books and library shelves to a text-based OPAC. Today many information resources can be accessed through the virtual library, including many online public access catalogs (OPACs) with sophisticated retrieval engines. Research shows, however, that novice users encounter difficulties in interacting with these systems (Borgman 1986). Yee (1991) has summarized these problems as finding appropriate subject terms, large numbers of hits and failure to reduce the retrieval sets, zero hits and failure to increase the retrieval sets, failure to understand cataloging rules, and spelling and typographical errors. In addition, lack of understanding of indexes, files, and basic database structure leads to the use of articles, stop words, entering author's first name before last name, and hyphenation problems. The interface and retrieval systems can also be a source of potential problems. Complex interfaces and the need for training and relearning when used infrequently, incomprehensible error and help messages, problems associated with displaying records and difficulties with Boolean logic have compounded the obstacles encountered by novice users. These restraints have prompted one researcher to state that the second-generation OPACs are powerful and efficient but are dumb, passive systems which require resourceful, active, intelligent human searchers to produce acceptable results (Hildreth 1989). Suggested Solutions To address the needs of end users and to alleviate the mentioned difficulties, many researchers have conducted experiments to enhance and improve OPACs. In general, research in this area may be divided into two broad categories: enhancing MARC records, and improving the retrieval engine and the interface. Many researchers (Cochrane 1986, Drabenstott et al. 1990, Chan 1990, Pejtersen 1989, Lawrence 1985) have demonstrated the value of augmenting MARC records and the online catalog with various schemes such as the inclusion of the Dewey Decimal Classification (DDC) schedules and relative indexes. Projects in Carnegie Mellon University and other institutions have attempted to enhance bibliographic records by adding table of contents of books (Greenwood 1989, Michalak 1990, Posey and Erdmann 1986). The addition of new information to MARC, however, can be very costly and unsuitable for individual libraries. Advancing the retrieval engine has involved ranking of documents, weighting index terms and automatic spell checking. Projects such as OKAPI (Online Keyword Access to Public Information) have attempted to use these techniques to build OPACs which do not require any user training (Greenwood 1989) Other researchers have strived to enhance the retrieval system by adding visual interfaces which use icons, graphical user interfaces, hypertext links and multimedia to help end users. Client/server architectures are used to take advantage of the power of today's microcomputers to present users with alternative interfaces. Kid's Catalog (Busey and Doerr 1993), OASIS (Buckland et al. 1992), Multimedia Visualizer (Lee 1991), the Science Library Catalog Project (Borgman et al. 1995) and XOkapi (Hancock-Beaulieu et.al. 1995) are just a few examples of these new interfaces. These OPACs are utilizing concepts that move users closer to direct manipulation of objects or documents. Hildreth (1989) states that these OPACs are more intuitive as the objects are manipulated directly avoiding previous layers of mental encoding/decoding and indirect representation searchers are usually required to pass through. …