Inside the DDCInside the DDC

Dewey goes Europe: On the use and development of the Dewey Decimal Classification (DDC) in European libraries

Austrian National LibraryVienna

28 April 2009

Joan S. MitchellEditor in Chief, DDCOCLCmitchelj@oclc.org

Outline

• Anatomy of a Dewey record

• What content is in the underlying data files?

• What content is associated with the scheme?

• How is the scheme represented?

796.932 Cross-country skiing

Number and caption

Notes

Relative Index terms

Mapped LCSH

Hierarchy

Content: English-language full edition database (December 2008)

Schedule numbers:26,715

Tables 1-6: 9,356

Built schedule numbers:13,310

Built table numbers: 609

Content: English-language abridged edition database (December 2008)

Schedule numbers: 4,937

Tables 1-4: 522

Built schedule numbers: 401

Built table numbers: 9

What content is associated with the DDC?

•Large number of resources

•Mappings and crosswalks

• Interoperable translations

DDC already associated with a large number of resources

• WorldCat

• ~25% of WorldCat records include explicit Dewey numbers plus more derived using FRBR work sets

• Number is growing, e.g., Deutsche Nationalbibliothek is now adding Dewey numbers to WorldCat nearly at the same rate as the Library of Congress

• Other utilities and databases, e.g., BIBSYS, NORART

• Digital libraries, e.g., World Digital Library

NORARThttp://www.nb.no/baser/norart/

World Digital Libraryhttp://www.wdl.org/

Mappings to subject headings (1)

Library of Congress Subject Headings (LCSH)

Medical Subject Headings (MeSH)

Canadian Subject Headings (CSH)

Sears List of Subject Headings (Sears)

Book Industry Standards and Communications (BISAC) Subject Headings

Mappings to subject headings (2)

RAMEAU [French]

Schlagwortnormdatei (SWD)[German]

Nuovo Soggettario [Italian]

Sears Lista de Encabezamientos de Materia [Spanish]

Crosswalks between DDC and other schemes

LCC – DDC (ClassWeb, Classify)

UDC – DDC (IZUM, Czech National Library)

SAB – DDC (Electronic updated version at National Library of Sweden)

Translations

796.932 Skilanglauf

Note more SWD mapped to 796.932 than LCSH

Representation

•Use of and extensions to MARC 21 formats for representation of the DDC

•New representations for semantic web applications

Representation: Dewey in MARC 21 Formats

•Use of MARC 21 formats for classification and authority data in new Editorial Support System

•Extensions to MARC to support representation and access (developed in cooperation with DNB, LC, and OCLC)

Dewey Class Record in MARC Classification Format

Relative Index Record in MARC Authority Format

Dewey Class Record in XML(excerpt)

Some Extensions to MARC 21 Bibliographic Format

•Representation of component parts of numbers

•Accommodation of full and partial “access” numbers

Component Parts of Numbers

Inclusion of component parts of numbers in bibliographic records using a new 085 field, based on the 765 field in the classification format

Component Parts Example

Artistic themes in literature

082 04 $8 1 $a 808.80357 $2 22

085 ## $8 1.1 $b 808.80 $a 808.801 $c 808.303 $z 3C $s 357

Collections of literary texts from more than two literatures displaying specific features

Artistic themes

Access Numbers

Provision for assignment of access numbers (additional DDC numbers, notation from Tables 1-6, internal table notation) in bibliographic records

Access Numbers: Examples (1)

History of Vienna, Linz, and Salzburg

082 00 $a 943.6 $2 22 (Austria)

083 0# $a 943.613 $2 22 (Vienna)

083 0# $a 943.624 $2 22 (Linz)

083 0# $a 943.632 $2 22 (Salzburg)

Access Numbers: Examples (2)

Geographic access in the British Library Newspaper Project:

Birmingham Post

083 0# $z 2 $a 424 $2 22 $q Uk (West Midlands)

083 0# $z 2 $a 42496 $2 22 $q Uk(Birmingham City)

New Forms of Representation

•Formal specification of relationships in the DDC (research project under way by Green and

Panzer on Dewey as an ontology—a direct response to Dr. Niggemann’s challenge at last year’s EDUG Symposium)

•Dewey URIs

•Dewey in RDF/SKOS

Uniform Resource Identifiers (URIs) for Dewey: Examples

Generic URI

http://dewey.info/class/338.4

Specific time

http://dewey.info/class/338.4/2007/05/25

http://dewey.info/class/338.4/e22

Specific time & language

http://dewey.info/class/338.4/2007/05/25/about.en

Specific time, language & format

http://dewey.info/class/338.4/2007/05/25/about.en.skos

Dewey in RDF/SKOS

SKOS (Simple Knowledge Organization System) provides a standard way to represent knowledge organization systems (KOS) using the Resource Description Framework (RDF)

Problem: Dewey is more complex than many KOS (e.g., thesauri)

• Schedules, auxiliary tables, internal tables, Relative Index

• Standard numbers, optional numbers; number spans, centered entries

• Elaborate note structure in tables and schedules + lengthy notes in the Manual

Analyzing DDC for modeling in RDF/SKOS (1)

370.11 Education for specific objectives

370.113 Vocational education

370.113085 Parents--vocational education

370.1130941 Vocational education--Great Britain

370.1130973 Vocational education--United States

Career development

Career education

Education of employees

Employee development

Human resource development …

Career education

Career education--United States

Career education--United States--Curricula

Core competencies

…

Vocational education

Vocational training centers

Relative Index

Mapped LCSH

skos:closeMatch

skos:closeMatch

Analyzing DDC for modeling in RDF/SKOS (2)

370.113 Vocational education

Class here career education, occupational training, vocational schools

Class on-the-job training, vocational training provided by industry in 331.2592

For vocational education at secondary level, see 373.246; for adult vocational education, see 374.013

See also 331.702 for choice of vocation; also 371.425 for vocational guidance in schools

skos:notation

skos:prefLabel

skos:related

skos:narrowerStructural

RDF model: Class

<class/370.113/2007/12> a skos:Concept ;

skos:inScheme <scheme/2007/12> ;

dct:created "1996-06-01T00:00:00.0-05:00"^^<http://purl.org/dc/terms/W3CDTF> ;

dct:modified "2003-03-26T00:00:00.0-05:00"^^<http://purl.org/dc/terms/W3CDTF> ;

skos:notation "370.113"^^<schema-terms/Notation> ;

skos:prefLabel "Vocational education"@en ;

skos:broader <class/370.11/2007/12> ;

skos:narrower <class/370.113085/2007/12> ,

<class/370.1130941/2007/12> ,

<class/370.1130973/2007/12> ;

skos:narrowerStructural <class/373.246/2007/12> ,

<class/374.013/2007/12> ;

skos:related <class/331.2592/2007/12>

.

RDF model: Relative Index terms

<class/370.113/2007/12> ddc:topic

<index/Career%20development> ,

<index/Career%20education> ,

<index/Education%20of%20employees> ,

<index/Employee%20development> ,

<index/Human%20resource%20development> ,

<index/Job%20training> ,

<index/Occupational%20training> ,

<index/Retraining%E2%80%94vocational%20education> ,

<index/Staff%20development> ,

<index/Training%E2%80%94employee%20education> ,

<index/Vocational%20education> ,

<index/Vocational%20schools> ,

<index/Vocational%20training> ,

<index/Work%20training> .

RDF model: Mapped LCSH

<class/370.113/2007/12> skos:closeMatch

<http://tspilot.oclc.org/lcsh/sh%2085020255%20> ,

<http://tspilot.oclc.org/lcsh/sh%2000002431%20> ,

<http://tspilot.oclc.org/lcsh/sh%2085144178%20> ,

<http://tspilot.oclc.org/lcsh/sh%2096002453%20> .

Some questions to frame the symposium

How can we improve/extend the content of the DDC?

How can we work together to make sure new forms of representation are interoperable?

How can we make Dewey in its various representations plus mapped terminologies and associated content work harder?

Some Useful DDC Links

Dewey web site http://www.oclc.org/dewey/

New & Changed Entries        http://www.oclc.org/dewey/updates/new/default.htm

Discussion papershttp://www.oclc.org/dewey/discussion/default.htm

025.431: The Dewey blog http://ddc.typepad.com

DDC Research Projects

Classify http://deweyresearch.oclc.org/classify2/

DeweyBrowser http://deweybrowser.oclc.org/ddcbrowser2/

EDUG IT http://www.slainte.org.uk/edugit/

Dewey URIs, RDF/SKOS representation of the DDC http://www.oclc.org/news/events/presentations/2008/ISKO/20080805-deweyskos-panzer.ppt