Library and Information Science

Among various techniques employed for indexing information, the approach through thesaurus organization is considered a lately developed new technique and is becoming fashion of a sort. However, the term “thesaurus” and the technique and method adopted for its compilation are not used in a consistent way. In this article, first the notion of “thesaurus” is clarified against similar products, secondly various sorts of thesauri are introduced and finally note and care to be taken for organizing a thesaurus are discussed especially in connection with mechanical or automatic processing verbal texts.

The main purpose of this article lies not in developing a scholarly discourse but in finding efficient way of compiling a thesaurus for a given objective. To carry out the task, it is necessary to pay attention to characteristics of historical development of a subject area and to the range of freedom of interpretation of a concept and an idea in the area. This means that if a thesaurus is used for linking ideas with words, it should be examined whether a standard system or classification of concepts and ideas can be usable in a subject area. If it is so, the role of a thesaurus is to provide linking between words and concepts systematically listed in a scheme and the linking may be done without too much difficulty. But if it is not so, it will be required to set up a certain number of systematic lists of concepts and ideas and each word must be identified with each concept or idea in each of the lists, thus making it much more difficult than the former.

In certain areas in natural science and technology the thesaurus approach may be very effective for information retrieval, but the same approach can be a failure in many of areas in social sciences and humanities unless enough precautions are given to a way of controlling the correlation between conceptual systems and words.