School of Information Management & Systems. Spring 2004.
245
Organization of Information in Collections.
Michael Buckland.
Assignment 6: Examine Thesauri. Due March 1.
.
There are various kinds of indexes that use words, most obviously simply
searching for any occurrence of some particular word that represents something
of interest to you, but authors and indexers may have used different words.
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"). Soon you will create a small thesaurus.
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 History Note ("HN" documenting decisions concerning use of this
term/phrase,
and the relationships between terms are made quite explicit,
generally in the
form
USE [= use some other heading] and its reciprocal USE FOR.
e.g. Asses USE Donkeys; Donkeys UF Asses. Usually relates synonyms and
near-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. 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 on left click on
About Indexing,
browse around, then from the menu on left click on
Resources then
Online Reference
Sources, the at the end of the first paragraph
click on
online
thesauri and
should reach
a list of web-accessible thesauri at
www.asindexing.org/site/thesonet.shtml
There are lots more at
http://hilt.cdlr.strath.ac.uk/Sources/thesauri.html and
http://www-cui.darmstadt.gmd.de/~lutes/thesauri.html.
Note tutorial at
http://instruct.uwo.ca/gplis/677/thesaur/main00.htm#contents.
3. Imagine adding your 2003 St. Valentine's Day card(s)
to an online database of materials in preparation for writing
your autobiography. Suppose you are about to assign the metadata
"Saint Valentine's Day card" as genre and "Courting" as a topical description.
Let's check
a thesaurus of terms related to graphic materials. 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
"Saint Valentine's 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
or
Darmstadt
lists of thesauri,
choose any one, find some terms of interest to yourself, and (very
briefly) report on what you found. Add any comments on what you have
learned about thesauri.