Making Visible Hidden Relationships in the Dewey Decimal Classification: How Relative Index Terms Relate to DDC Classes 10 th International ISKO Conference.

Making Visible Hidden Relationships in the Dewey Decimal Classification:

How Relative Index Terms Relate to DDC Classes

Making Visible Hidden Relationships in the Dewey Decimal Classification:

How Relative Index Terms Relate to DDC Classes

10th International ISKO Conference

August 6, 2008

Rebecca Green

Assistant Editor

Dewey Decimal Classification

Example classExample class

796.86 Fencing

Including bojutsu, kendo

Class here sword fighting

RI: BojutsuFencing (Swordplay)KendoSword fightingSwordplay

DDC classesDDC classes

Class as gathering point for set of topics

Caption

Including concepts

Class here concepts

Topics either equal / approximate whole of class or are in standing room in class

Topics in classesTopics in classes

Approximating the whole vs. standing room:

Standard subdivisions can only be added for topics that approximate the whole of the class, not for those in standing room

Future expansion anticipated for topics in standing room, not for those that approximate the whole

Topics in class-here notes approximate the whole of the class; topics in including notes are in standing room

Relative Index terms and class topicsRelative Index terms and class topics

Explicitly: Relative Index terms index class as whole

Implicitly: Relative Index terms associated with specific topics in classSpecific associations not recorded

Thus, unknown if Relative Index term topic approximates the whole of the class or is in standing room there

Project attempts to make this designation automatically

MotivationMotivation

Correct decision on addition of standard subdivisions

Maintenance of scheme: If topic moves to another class, associated Relative Index term should, too

Support automated operations on scheme, e.g., creation of derived versions

DifficultiesDifficulties

Identification of topics

Topics in caption

In multitopic caption, topics may approximate whole or be in standing room

Paraphrase relationship between topics in schedules and Relative Index terms (morphological, syntactic, semantic)

ExampleExample

133.3 Divinatory arts Including fortune-telling by

bones, dice, pendulum

Relative Index terms:Bones—divinationDice—divinationPendulums—divination

Standard subdivisions noteStandard subdivisions note

749 Furniture and accessories

Standard subdivisions are added

for furniture and accessories

together, for furniture alone

Two-phase approachTwo-phase approach

In schedules

Isolate topics

Determine if topics equal / approximate whole of class (AW) or are in standing room (SR)

Match Relative Index terms to schedule topics, using series of increasingly more relaxed strategies

Topic isolationTopic isolation

Sign languages used primarily for purposes other than communication of deaf people

Systems programs Operating systems

Satellites and rings; eclipses, transits, occultations

Religious experience, life, practice [can’t parse reliably]

Approximates-the-whole topicsApproximates-the-whole topics

All topics in class-here note

Topic in single topic caption

Topic in multitopic caption, with note that standard subdivisions are added for:

Any or all topics in heading

Either or both topics in heading

The specific topic alone

Standing room topicsStanding room topics

All topics in including notes

Topic in multitopic caption, with note for adding standard subdivisions, not meeting criteria for approximating the whole

Topic in multitopic caption, without note for adding standard subdivisions, that matches topic in subordinate caption

Matching RI terms to topics:EXACT matchMatching RI terms to topics:EXACT match

121 Epistemology (Theory of knowledge)

121.63      Certainty and probability

Standard subdivisions are added for

either or both topics in heading

RI: Probabilities—epistemology (AW)

Matching RI terms to topics:IN matchMatching RI terms to topics:IN match

620 Engineering

627.52      Irrigation

Class here construction and use of irrigation canals

RI: Irrigation canals—engineering

(AW)

Matching RI terms to topics:KEYWORD matchMatching RI terms to topics:KEYWORD match

384.14      *Activities and services

Including Morse and other code telegraphy, printing telegraphy; stock tickers, teletype, telex; comprehensive works on facsimile transmission

RI: Morse code telegraphy (SR)

Matching RI terms to topics:KEYWORD matchMatching RI terms to topics:KEYWORD match

384.51      *Satellite communication

RI: Communications satellites (AW)

384.54      *Radiobroadcasting

Class here public broadcasting (noncommercial broadcasting), public aspects of amateur radio, interdisciplinary works on radiobroadcasting and television broadcasting

RI: Noncommercial radio (AW)

Matching RI terms to topics:PARTIAL (50%+) matchMatching RI terms to topics:PARTIAL (50%+) match

748    Glass

748.6      Methods of decoration

RI: Decorative treatment—glass (AW)

ResultsResults

EXACT IN KEYWORD

PARTIAL

TOTAL

Approximates whole

11335

(24.4%)

4209

(9.0%)

1241

(2.7%)

5189

(11.2%)

21974

(47.2%)

Standing room

3116

(6.7%)

4064

(8.7%)

952

(2.0%)

1513

(3.3%)

9645

(20.7%)

Unknown status

1042

(2.2%)

1479

(3.2%)

584

(1.3%)

1091

(2.3%)

4196

(9.0%)

Total 15493

(33.3%)

9752

(21.0%)

2777

(6.0%)

7793

(16.8%)

35815

(77.0%)

Future improvements (1)Future improvements (1)

Observe hierarchical force

302 Social interaction

Class here . . . social psychology

302.24 Content

Including gossip, rumor

RI: Rumor—social psychology

Future improvements (2)Future improvements (2)

Don’t require match on Relative Index qualifier

335.2 Systems of French origin

Including Babouvism, Icarianism

RI: Babouvism (Socialist school)

Future improvements (3)Future improvements (3)

Introduce stopwords for general terms

748    Glass

748.6      Methods of decoration

RI: Decorative treatment—glass (AW)

Future improvements (4)Future improvements (4)

Locally reverse treatment of main heading and subheading

220 The Bible

224 Prophetic books of Old Testament

224.1 Isaiah (Isaias)

RI: Bible. O.T.--Isaiah