School of Information Management & Systems.   Spring 2002.
245 Organization of Information in Collections.   Michael Buckland.

Assignment 7: Use a Thesaurus. Due Feb 22. REVISED DUE DATE.

There are various kinds of indexes that use words, most obviously simply searching for any occurrence of some particular word that represents a topic of interest to you, but may not have been used for that topic by the author There are "controlled vocabulary" indexes that establishing preferred forms of words and creates cross-references from "non-preferred" but closely-related words (synonyms, antonyms) and also between preferred terms that are hierarchically or otherwise related. Examples of the controlled vocabulary indexes include lists of subject headings, back-of-book indexes, and thesauri. There is no fundamental difference between a Thesaurus (plural "thesauri") and a list of subject headings, but, generally, thesauri contain only single words or phrases as headings, distinguish between "preferred" and "not-preferred" terms and specify relationships between terms. Subject headings typically do the same, but also support complex composite statements with an internal syntactical structure (e.g. the LCSH heading Ireland -- Folklore -- Congresses), made up of multiple elements strung together (following rules) by the indexer (aka "pre-coordinate indexing"). In this exercise you examine some examples of thesauri.

A thesaurus generally has single terms (or phrases) suitable for a searcher to combine in Boolean searches (aka "post-coordinate indexing"). Usually there is a Scope Note ("SN") to clarify the definition) and the relationships between terms are made quite explicit, generally in the form
USE [= use some other heading] and its reciprocal USE FOR - for synonyms.
e.g. Asses USE Donkeys; Donkeys UF Asses. Usually relates synonyms.
NT = "See also the Narrower Term" and its reciprocal
BT = "See also the Broader Term": Dogs NT Spaniels; Spaniels BT Dogs.
RT = "See also the related term": Birds RT Ornithology. And sometimes
SA = "See also": Dog breeds SA names of specific breeds, e.g. bloodhounds, collies, pitbulls...
Ability testing SA subdivision Ability testing under subjects, e.g. Dentists--Ability testing.

1. Before you start, read David Batty's "WWW --- Wealth, Weariness or Waste: Controlled vocabulary and thesauri in support of online information access" D-Lib Magazine. November 1998. www.dlib.org/dlib/november98/11batty.html.

2. Then go to the American Society of Indexer's website www.asindexing.org/
In the menu top left click on Reference Sources on the Internet, the at the end of the first paragraph click on online thesauri and should reach a list of web-accessible thesauri www.asindexing.org/site/thesonet.shtml
Postscript Feb 16: Lots more to choose from at http://hilt.cdlr.strath.ac.uk/Sources/thesauri.html.

3. Imagine that you had decided to add your 2002 St. Valentine's Day card to an online database of materials that you are assembling in order to write your autobiography. Suppose that you are about to assign the metadata "St. Valentine'e Day card" as genre and "Courting" as a topical description. Let's make sure you are doing it right by checking a thesaurus of terms related to graphic materials, so click on Thesaurus for Graphic Materials which is in two parts.
TGM I: Subject Terms which has terms for use in describing what is depicted and
TGM II: Genre and Physical Characteristic Terms which has terms for describing the form of material.
Find the records for the headings the Library of Congress would use for "Courting" (in TGM I) and for "St. Valentine-day card" (in TGM II). When you find them, take a quick look at the related and broader terms.

4. Go back to ASI list [or the HILT list] of online thesauri, choose any one, look up some terms of interest to yourself, and (very briefly) report on what you found. Add any comments on what you may have learned about thesauri from this exercise.