The Future of Subject Headings: Pre- vs. Post-Coordination

After the advent and development computer technology, Pre- vs. Post-Coordination has been considered as an important issue in information storage and retrieval. From the 1950's to present, pros and cons comparison of keyword system and controlled vocabulary is concerned. With the review of related literature, a key question about the future of subject headings in the Third Millennium was concerned and appropriate strategies were proposed. Subject headings as a pre-coordinated system provide context, suggestibility, browsability and precision, capabilities which do not exist in post-coordinated system. Thus it can play a critical role in information organization in the Third Millennium. However, the list of subject headings has disadvantages, such as complexity of subject assignment rules, the cost of pre-coordination, and difficulty in understanding of subject strings by users, issues that should be resolved. Appropriate strategies for the future of subject headings are: more automation for subject assignment with smart technology, simplifying subject assignment rules, and developing a new search engine with new display abilities, such as ontology and information visualization.