Introduction

Now that there are a number of excellent computer programs that assist indexers with the drudgery of organizing and presenting an index, we have the luxury of considering how to increase our skills and expertise on the most important and hardest part of indexing: analyzing the text and creating index entries.
This paper discusses faceted classification and suggests that it can be appropriate for use as an aid to indexing.

Background - Enumerative Classifications

Most of us have at least a passing familiarity with classification schemes such as the Dewey Decimal Classification (DDC) or the Library of Congress Classification (LCC). The DDC, first published in 1876, was originally designed for the arrangement of books on library shelves. The LCC, published and maintained by the U.S. national library, is used, along with the widely known multi-volume publication the Library of Congress Subject Headings, to classifiy the millions of documents and artifacts in the library's vast collections.
Both DDC and LOC, along with such others as the Universal Decimal Classification (known as UDC), are examples of enumerative classifications. That is, they aim to enumerate or list all the subjects present in the literature that the scheme is intended to classify.

The enumeration is normally achieved by first identifying the main disciplines to be covered by the scheme, either on a philosophical or pragmatic basis, and allocating each a main class. Then each discipline is divided into subclasses. This process of subdivision is continued until an appropriate level of specificity has been achieved. The object is to provide one place, and one place only, for each subject.
For example, the DDC classifies "Philosophy and Psychology" as class 100, which is further broken down into 100: Philosophy, 110: Metaphysics, 120: Epistemology, etc. Many enumerative schemes are thus also hierarchical.

Enumerative classifications are essentially top-down methods of analysis: you start at the top of the hierarchy and work your way down until you find a suitable heading or term that describes or classifies your text.

Faceted Classification

In addition to the many enumerative schemes, there also exists a completely different system of classification: faceted classification. And faceted classifications, unlike enumerative, are bottom-up systems. That is, they start with the objects being classified and use those as the basis for the descriptions.

Originated by the noted librarian S. R. Ranganathan in the 1930s, faceted classification arose from the need to accommodate complex or multi-concept subjects. Jennifer E. Rowley, in her book Organizing Knowledge, notes that what Ranganathan recognized was that the world of knowledge was growing quickly, with new areas of knowledge being discovered and new ways to combine existing subjects. He understood that any classification that attempted to enumerate a finite number of subjects without full capabilities for expansion to allow for new areas of knowledge could never meet the needs of the future.

About Facets

Ranganathan wanted to classify knowledge into broad classes that were then broken down into basic concepts or elements according to certain characteristics, called facets. He proposed five basic types of facets that may occur in many subject fields: personality, matter, energy, space and time.
Facets of any specific collection, however, are determined by an evaluation of the nature of the items in that collection. Other examples of facets include:

• Subjects: general or specific
• Language: multilingual or individual language
• Geography: global or national
• Creating/supporting body
• User environment: home, school, office
• Format: book, photograph, MP3file
  

If you're having difficulty grasping the term "facet," think of it as a characteristic or an attribute. A simple example might help.

Think of a toy ball. How would you describe it? "Round," "soft," "red," "smooth," "large," "striped" might be some of the words you would use. Or perhaps "hard," "white," "small," "dimpled." These sets of terms can be generalized to form a set of mutually exclusive characteristics (facets):

• Color
• Shape
• Size
• Texture
• Weight
• Use

Now you have a set of facets that can be used to describe any ball or, for that matter, any number of other objects.

Application of Faceted Classification to Indexing

All this is is entirely fascinating, you're thinking, but what does it have to do with indexing?
Using faceted classification can help you analyze your text and can assist in making sure you capture all the relevant items that should be indexed.

Take some time before you begin indexing to think about the facets that will most likely be important as you work through the text. We're all familiar with the standard "people, places, things, ideas." But suppose that you're working on a biography, for example. In this instance you might consider the following as important facets:

• Family
• Other relationships
• Training/Education
• Travels
• Places lived
• Career
• Publications
  

Or perhaps you're indexing a cookbook. Your important facets might be:

• Ingredients
• Techniques
• Holidays
• Recipe titles
  

In a software manual, you might have:

• Operations
• Commands
• Shortcuts
  

Whatever list you come up with, post it in a prominent place. Then, if you're having trouble with a certain passage in the text, check your list of facets as a reminder of the kinds of things you have decided are important.

Now I'm not saying that you should necessarily use the facets as headings (although you might; it depends on the context, you know). If you do, you'll end up with lots of classified lists, not usually the best thing for an index.

You might also use your list of facets as an aid to ensuring the exhaustivity of your indexing, much like a checklist: Have I picked up all the recipe titles or techniques in this paragraph or on this page? Is there a facet I've missed? Also, have I placed this term under all the appropriate facets? e.g., Broccoli Cheese Casserole should be under: (1) ingredients: broccoli, (2) recipe titles: Broccoli Cheese Casserole and (3) techniques: baking.

Using facets as the basis for your indexing can also help assure consistency, that you're indexing the same kinds of things throughout the course of the text.
Of course, you might find that as you work through the text the list of facets needs to be expanded, or perhaps one item should be deleted. Don't worry. That simply means that you're gaining a greater understanding of the text. But if you do add a facet, you might want to go back over what you've already indexed to make sure you've included items representing the new facet.

Conclusion

No matter what your style of indexing, no matter what software you own, no matter whether you're a full- or part-time indexer, be you in-house or freelancer, you may find that using facets as an aid to indexing can help you produce better, more consistent indexes. Your readers should be happier and so should your editors.

Bibliography

Books

Fidel, Raya, Trudi Bellardo Hahn, Edie M. Rasmussen and Philip J. Smith, eds. Challenges in indexing electronic text and images. ASIS monograph series. Learned Information, Inc. (Medford, NJ: 1994)

Rowley, Jennifer. Organizing knowledge: an introduction to information retrieval. 2d ed. Gower Publishing (Aldershot, England: 1995)

Articles

Furnas, George W., and Jeff Zacks. Multitrees: enriching and reusing hierarchical structure. Association for Computing Machinery (1994).

Glassel, Aimee. Was Ranganathan a Yahoo!? http://www.scout.cs.wisc.edu/toolkit/enduser/archive/1998/euc-9803.html

Maple, Amanda. Faceted access: a review of the literature. Music Library Association, Bibliographic Control Committee. http://www-sul.stanford.edu/depts/music/mlatest/BCC/BCC-Historical/95WGFAM2.html

Pollitt, A. Steven. Interactive information retrieval based on faceted classification using views. Center for Database Access Research, University of Huddersfield, England. http://www.hud.ac.uk/schools/cedar/dorking.htm

Pollitt, A. Steven, Martin P. Smith and Patrick A. J. Braekevelt. View-based searching systems-a new paradigm for information retrieval based on faceted classification and indexing using mutually constraining knowledge-based views. School of Computing and Mathematics, University of Huddersfield, England. http://www.hud.ac.uk/schools/cedar/bcshci.htm

Web Developer's Virtual Library. The web librarian. http://wdvl.com/Location/WLn/

Weinberg, Bella Hass. Complexity in indexing systems-abandonment and failure: implications for organizing the internet. American Society for Information Science (1996). http://www.asis.org/annual-96/ElectronicProceedings/weinberg.html