The research trends in the topic of subjects were well summarized in the program titled "Crisis in Subject Cataloging and Retrieval," held at the 1995 ALA Annual Conference. In that program, Arlene Taylor pointed out the following signs of the crisis in subject cataloging: lack of administrative support, lack of sufficient education in the theory and practice of subject analysis, negative view of the Library of Congress Subject Headings, availability of keyword searching, insufficiency of subject analysis for handling different formats, and the expanding online environment. Thomas Mann, on the other hand, in his talk on "Cataloging and Reference Work," emphasized the continuing need for subject classification of books and the importance of specific entries in a controlled vocabulary. He suggested that part of the crisis is due to the lack of subject instruction for the library users in general. Michael Gorman, in his talk on the cost and value of organized subject access, made it clear that systematic subject access is the key to effective use of libraries and that effective retrieval is impossible without authority control. In sum, the research on subjects since 1995 has centered on examinations of effectiveness of the subject access and has urged improvement in specific environments for particular forms of materials.
Topics of the articles selected below fall into four areas: retrieval and usefulness of subject headings, subject authority control, keyword versus controlled language, and multilingual display of subject headings.
Practical concern about the issue of retrieval and usefulness of subject headings has been a popular topic for many authors. Down (1995) and DeZelar-Tiedman (1996) discussed the enhancement of subject access in four areas (form/ genre, characters, geographical setting, and topical headings) to individual works of fiction based on the observation of the OCLC/Libryar of Congress (LC) Fiction Project. Mowery (1995) surveyed the subject headings and classification numbers in catalog records for books on Chicano literature and pointed out that the subject cataloging of the works of Chicano authors is especially problematic. Miller (1996) focused on the ambiguities in the Library of Congress Subject Headings for form and genre access to moving image materials. Chan and Vizine-Goetz (1997) examined recurring patterns of invalid (either erroneous or obsolete) headings from a sample of 9,442 headings by the Library of Congress to bibliographic records. Although they found that the overall error rate is low, they suggested that an awareness and understanding of patterns of errors in subject heading strings could help improve the quality and efficiency in subject authority control. Based on a case study at Virginia Tech, Sapon-White and Hansbrough (1998) stated in their article that dissertations with subject headings in their bibliographical records are more likely to circulate, and circulate more often than those without subject headings. Wilbur, on the other hand, found only a small margin of difference in his comparison of group and individual performance of the document retrieval task (1998) between subject experts and untrained workers .
The topic of subject authority files is not only closely connected to the improvement of bibliographic retrieval, but also indispensable to the international cooperation of subject indexing among libraries around the world. In their article on subject searching, Wilkes and Nelson (1995) attempted to compare the results of subject searching in two online catalog systems, one with authority control, and the other without. Williamson (1997) pointed out that standardization of subject access is an important factor in national and international networking, cooperation, and exchange of bibliographical data. In her article on authority control in Germany, Kelm (1996) stated that, on the basis of a multilingual subject authority file, libraries can cooperate in the field of subject indexing through all participating European countries and languages. Chan and Vizene-Goetz (1998) studied the feasibility of automatically creating a subject heading validation file by scanning the OCLC Online Union Catalog and concluded that an automatically generated subject heading file is indeed feasible. The validation file would be useful in verifying subject heading strings, updating subject headings in data maintenance, and validating subject headings for retrospective conversion.
In the ever-changing online environment, the choice of keyword versus controlled vocabulary searches has become a major point of discussion in the field of library and information sciences. Most studies (Curl 1995, McJunkin 1995, Hildreth 1997, Muddamalle 1998) have shown that the natural language/keyword search and controlled vocabulary search both yield very effective retrieval results with marginal limitations. However, users of the online catalog search more often by keyword than by any other type of search. The key finding is that in order to achieve optimal retrieval, a combination of natural language search and controlled vocabulary search should be adopted. In addition to this controversy, new terminology, such as “subject gateway”, has been created for network-based resource access. In “Cross-Searching Subject Gateways,” Kirriemuir and his co-authors (1998) defined subject gateways “as some facility that allows easier access to network-based resources in a defined subject area,” described the characteristics of some of the subject gateways currently accessible through theWeb, and looked at some of the issues facing subject gateway development in the near future.
In the online environment, subject access has become a major path to effectively retrieve materials in the ocean of knowledge. Previous surveys also showed that Library of Congress Subject Headings have been adopted in libraries around the world. In "Subject Cataloging in Pakistani Libraries," Mahmood (1997) pointed out that the subject headings lists available in English-speaking countries lack suitable headings for Asian subjects. He suggested the compilation of a comprehensive list of subject headings for Pakistani books written in Arabic script. Kelm (1996), in her article on subject authority files in Germany mentioned above, proposed international cooperation of multilingual subject authority file in the field of subject indexing by all participating European countries and languages.
Potential Topics for Further Research
- Recommendations for structural modification of Library of Congress Subject Headings for the changing formats
- More exploration of enhancements in current cataloging conventions and MARC record structure to allow enhanced subject and/or keyword access in bibliographic retrieval
- Recommendations for guidelines on subject searching in Web-based OPACs
- Evaluation of Web subject search, organization, and design
- Continued evaluation of the keyword search versus controlled language search in the Web-based online environment
- Analysis of vocabulary control in the Library of Congress Subject Headings
- International standardization of subject heading languages
- Discussion of multiple languages and character sets in the subject headings authority systems, nationally and internationally
- Case studies of multilingual thesaural links between the heading in the Library of Congress Subject Headings authority file and the authority files of other languages
Chan, Mai Lois, and Diane Vizine-Goetz. 1997. Errors and obsolete elements in assigned Library of Congress Subject Headings: Implications for subject cataloging and subject authority control." Library Resources & Technical Services 41, no. 4 (Oct.): 295–322.
Chan, Mai Lois, and Diane Vizine-Goetz. 1998. Toward a computer-generated subject validation file: Feasibility and usefulness." Library Resources & Technical Services 42, no. 1 (Jan.): 45–60.
Curl, Margo Warner. 1995. Enhancing subject and keyword access to periodical abstracts and indexes: Possibilities and problems. Cataloging & Classification Quarterly 20, no. 4: 45–55.
DeZelar-Tiedman, Christine. 1996. Subject access to fiction: An application of the guidelines. Library Resources & Technical Services 40, no. 3 (July): 203–08.
Down, Nancy. 1995. Subject access to individual works of fiction: Participating in the OCLC/Library of Congress iction Project. Cataloging & Classification Quarterly 20, no. 2: 61–69.
Ferl, Terry Ellen, and Larry Millsap. 1996. The knuckle-cracker's dilemma: A transaction log study of OPAC subject searching. Information Technology and Libraries 15, no. 2 (Jun): 81–98.
Hildreth, Charles R. 1997. The use and understanding of keyword searching in a university online catalog. Information Technology and Libraries 16, no. 2 (June): 52–62.
Kelm, Barbara. 1996. The subject authority file in Germany. International Cataloguing and Bibliographic Control 25, no. 3 (July/Sept.): 62–66.
Kirriemuir, John, et al. 1998. Cross-searching subject gateways: The query routing and forward knowledge approach. D-Lib Magazine (Jan.): Accessed Oct. 10, 2002 http://www.dlib.org/dlib/january98/01kirriemuir.html.
Mahmood, Khalid. 1997. Subject cataloging in Pakistani libraries. International Cataloguing and Bibliographic Control 26, no. 3 (July/Sept.): 68–70.
McGarry, Dorothy. 1996. Guidelines for subject authority and reference entries. International Cataloguing and Bibliographic Control 25, no. 3 (July/ Sept.): 67–68.
McJunkin, Monica Cahill. 1995. Precision and recall in title keyword searches. Information Technology and Libraries 14, no. 3: 161–71.
Miller, David. 1995. Ambiguities in the use of certain Library of Congress Subject Headings for form and genre access to moving image materials. Cataloging & Classification Quarterly 20, no. 1: 83–104.
Miller, David. 1997. Identical in appearance but not in actuality: Shared by a subject-access and a form/genre authority list. Library Resources & Technical Services 41, no. 3 (July): 190–204.
Mowery, Robert L. 1995. Subject cataloging of Chicano literature. Library Resources & Technical Services 39, no. 3: 229–37.
Muddamalle, Mauikya Rao. 1998. Natural language versus controlled vocabulary in information retrieval: A case study in soil mechanics. Journal of American Society for Information Science 49, no. 10 (Aug.): 881–87.
Olson, Tony, and Gary Strawn. 1997. Mapping the LCSH and MeSH systems. Information Technology and Libraries 16, no. 1 (Mar.): 5–19.
Plaunt, Christian, and Barbara A. Norgard. 1998. An association-based method for automatic indexing with a controlled vocabulary. Journal of American Society for Information Science 49, no. 10 (Aug.): 888–902.
Ressel, Maggie, and Vicki Toy Smith. 1998. A new approach to thesis subject analysis: A collaborative success. Cataloging & Classification Quarterly 26, no. 3: 41–49.
Roe, Sandy. 1999. Online subject access. Journal of Internet Cataloging 2, no. 1: 69–78.
Sapon-White, Richard, and Mary Hansbrough. 1998. The impact of Subject Heading assignment on circulation of dissertations at Virginia Tech. Library Resources & Technical Services 42, no. 4 (Oct.): 282–91.
Steinhagen, Elizabeth N. 1996. Cataloging news: A program titled "Crisis in subject cataloging and retrieval." Cataloging & Classification Quarterly 22, no. 2.
Stone, Alva. 1996. Up-ending Cutter's pyramid: The case for making subject references to broader terms. Cataloging & Classification Quarterly 23, no. 2: 5–16.
Taylor, Arlene G. 1995. On the subject of subjects. Journal of Academic Librarianship 21, no. 6: 484–91.
Tillotson, Joy. 1995. Is keyword searching the answer? College and Research Libraries 56, no. 3: 199–206.
Wan, Tian-Long, et al. 1997. Experiments with automatic indexing and a relational thesaurus in a Chinese information retrieval system." Journal of American Society for Information Science 48, no. 12 (Dec.): 1086–96.
Weimer, Katherine H. 1996. The nexus of subject analysis and bibliographic description: The case of multipart videos." Cataloging & Classification Quarterly 22, no. 2: 5–18.
Wilkes, Adeline W., and Antoinette Nelson. 1995. Subject searching in two online catalogs: Authority control vs non-authority control. Cataloging & Classification Quarterly 20, no. 4: 57–79.
Williamson, Nancy J. 1997. The importance of subject analysis in library and information science. Technical Services Quarterly 15, no. 1/ 2: 67–87.
Wilson, Mary Dabney. 1998. Specificity, syndetic structure, and subject access to works about individual corporate bodies. Library Resources & Technical Services 42, no. 4 (Oct.): 272–81.
Xu, Hong and F.W. Lancaster. 1998. Redundancy and uniqueness of subject access points in online catalogs. Library Resources & Technical Services 42, no. 4 (Oct.): 61–66.
Prepared by Wen-ling Liu, East Asian Unit Supervisor, Technical Services Dept., Indiana University, Wliu@indiana.edu.