Indexing: From Thesauri to the Semantic Web

By Piet de Keyser

Indexing consists of both novel and more traditional techniques. Cutting-edge indexing techniques, such as automatic indexing, ontologies, and topic maps, were developed independently of older techniques such as thesauri, but it is now recognized that these older methods also hold expertise.Indexing describes various traditional and novel indexing techniques, giving information professionals and students of library and information sciences a broad and comprehensible introduction to indexing. This title consists of twelve chapters: an Introduction to subject readings and theasauri; Automatic indexing versus manual indexing; Techniques applied in automatic indexing of text material; Automatic indexing of images; The black art of indexing moving images; Automatic indexing of music; Taxonomies and ontologies; Metadata formats and indexing; Tagging; Topic maps; Indexing the web; and The Semantic Web.

• Makes difficult and complex techniques understandable
• Contains may links to and illustrations from websites where new indexing techniques can be experienced
• Provides references for further reading

• Language: English
• Publisher: Elsevier Science
• Release date: Sep 10, 2012
• ISBN: 9781780633411

Piet de Keyser

Piet de Keyser is head librarian of the Katholieke Hogeschool Leuven, an institute for higher education in Louvain, Belgium. He published many articles on literary history, philosophy and library sciences. He teaches indexing in a Belgian Library and Information Sciences school.

Book preview

Ethiopia.

1

Introduction to subject headings and thesauri

Abstract:

This chapter provides an introduction to traditional controlled vocabularies, i.e. subject headings and thesauri. Both are highly used in libraries, but only for thesauri are standards still updated. The main difference between both kinds is that subject headings are precoordinate and thesauri are postcoordinate. Notwithstanding this, basic rules can be formulated that apply to both types. This chapter also deals with some practical aspects of controlled vocabularies, i.e. where they can be found, how they can be created or maintained. The purpose of this chapter is not to treat controlled vocabularies in depth, but to give the reader a general overview as a reference point for the next chapters.

Key words

controlled vocabularies

thesauri

subject headings

thesaurus software

precoordinate

postcoordinate

Finally, the thesaurus is like a taxonomy on steroids.

(Gene Smith [1])

Introduction

Libraries use more than one system to tell their patrons what a document is about – and they mostly use a mix of different instruments. A traditional library, whose main activity consists of collecting books and keeping them at the disposal of the public, will classify them according to a classification scheme, e.g. the Dewey Decimal Classification (DDC), the Universal Decimal Classification (UDC), or the Library of Congress Classification (LCC), etc. In a classification each subject is represented by a code; complex subjects may be expressed by a combination of codes. In fact this should be enough to express the contents of a document, and a flexible classification, e.g. UDC, allows the expression of each subject adequately, no matter how specific it may be.

The reality, however, is that libraries see classification mainly as an instrument to arrange their books on the shelves, as the basis for the call number system, and as a consequence of this a rich and very detailed classification like UDC is reduced to a scheme with broad classes because of the simple fact that the long string of numbers and characters of a detailed UDC code does not fit onto a relatively small book label; moreover, every librarian knows that only a few readers have any idea what is hidden behind the notations of the library classification. Frankly, the readers do not care; they just want to know where to find the book they