School of Information Management & Systems. Spring 2001.
245
Organization of Information in Collections.
Michael Buckland.
Assignment 7: Use a Thesaurus. Due Feb 21.
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 and a list of subject
headings, but, generally, thesauri contain only single words or phrases
as headings and
subject headings may support
complex composite statements with an internal syntactical
structure (e.g. the LCSH heading Ireland -- Folklore -- Congresses),
making
multiple elements strung together 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. Dowsing USE Divining-rod; Divining Rod UF Dowsing. 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. bloodhound, collies,...
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 "About Indexing" -- then
on "Thesauri" in the main menu -- then, at the bottom of the page,
click on
"online thesauri".
You should reach
a list of web-accessible thesauri
www.asindexing.org/thesonet.shtml
3. Imagine that you had decided to add your St. Valentine-day cards
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-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 of
online thesauri pick
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.