MetaLib WorkshopDie Deutsche Bibliothek

In the Shadow of Brunelleschi’s Dome

A lesson in metadata development

Stuart L. WeibelDirector, Dublin Core Metadata Initiative

Frankfurt, Germany October 21, 2002

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DC-2002Florence – October 13-17

• 215 participants from 25 countries• Conference papers, tutorial program, Working

group meetings• Corporate metadata track• Accessibility metadata track• Semantic Web Advanced Development track• DC-Government, Environment, Education, Library

working groups• Developments in Agent element qualifiers, Type

list additions

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Participation in the Initiative

• Community of over 1500 experts and practitioners from 1000 organizations in 50 countries

• 15 working and interest groups• Libraries, (digital) libraries, education,

museums, governments, supra-governmental organizations, environment, commerce, networking infrastructure

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dc:description• What is the value we are creating?

– Easier discovery– Better organization– Improved manageability– Greater liquidity of information

– A community of social capital investment

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Creation of Value in the Marketplace of Products

Value Creation Process

Management

Stockholders

Raw materials

Products and Services

Customers

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Creation of Value in the Standards Marketplace

Derivative value created by adopters

in applications,

data, and services

Stakeholders

Value Creation Process

Management

IdeasSocial Capital

StakeholdersbecomeAdopters

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dc:identifier• What makes DCMI uniquely identifiable

(and valuable) as a metadata initiative?

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The I’s have it…

• International– 20 countries represented at DC-2002

• Independant– OAI, RDF Recombinant metadata, cross

disciplinary consensus

• Open (Influenceable)– Governance and decision-making based on

open participation and public process

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dc:relation• What is the relationship of DC to the

larger resource description community, and to other metadata formats?

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The Resource Grid

high low

low

high

stewardship

BooksJournalsNewspapersGovernment docsAudiovisualMapsScores

Special collectionsRare booksLocal/Historical NewspapersLocal history materialsArchives & manuscriptsTheses & dissertations

Freely-accessible web resourcesOpen source softwareNewsgroup archives

Institutional repositories •ePrints•Learning objects/materials•Research data

high low

low

high

stewardship

uni

que

ne

ss

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Metadata Standards in the Resource Grid

BooksJournals

Special collections

Freely-accessible web resources

high low

low

high

stewardship

uniq

uene

ss

MARC, DCONIX, MPEG

MARC, DCONIX, MPEG

MARC, METS, EAD, DC, TEI

MARC, METS, EAD, DC, TEI

DCDC

DC, DDI, IEEE/LOM, FGDC, EAD, TEI, SCORM

DC, DDI, IEEE/LOM, FGDC, EAD, TEI, SCORM

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dc:format[s]• The DC community includes many

overlapping communities of practice

– HTML• Yes, people are still doing it

– XML• More structure, in well-defined packages that look

familiar to us

– RDF• Yes, people are still trying to figure it out • (and the SWAD group is here to help!)

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Pre-coordinated interoperability

• Pre-coordinated agreementsAgreed-upon semanticsAgreed-upon structureAgreed-upon syntax

• MARC/AACR2– Well established, rich metadata

• DC and XML-Schemas (ala OAI)– Cross disciplinary metadata language

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XML Schemas declare the particular element sets spoken by a given OAI Server

DC is the base interoperablity element set

Discipline-specific schemas are encouraged

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OAI interoperability derives from one (DC) or more common schemas per

server

OAI-1

OAI-3

OAI-2

OAI-4

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Recombinant Interoperability

• Agreed upon architectures for declaring semantics, with dynamically defined semantics– Semantic architecture

• DC core elements and qualifiers• Discipline-specific extensions (Application Profiles)

– Syntactic architecture• Resource Description Format (RDF)• RDF Schema declarations

– Property subclasses inherit attributes of parent classes– Interoperability granularity is at the element level rather

than the schema level

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How to do it

• RDF schemas declare elements as sub-properties of DC elements where applicable– Eg. AGLS:title is a sup-property of DC:title

• Define discipline-specific extensions as necessary• Cross-application indexing works for common

elements (element granularity rather than schema granularity)

• Organizations retain branding value of their respective namespaces while achieving global interoperability

• Registered Schemas will promote ability to identify and index related data sets

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Element Granularity Interoperability

DCFAO-AGMESDeclared as

Subproperties of DC

AGLSDeclared as

Subproperties of DC

All common properties searchable as DC elements

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dc:whither?

http://www.comune.firenze.it/servizi_pubblici/turismo/C05G.jpg

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Brunelleschi’s Dome as a metaphor for technology development

• Francesco Talenti’s 1366 design for Il Duomo called for a dome that surpassed the architectural limits of his day

• 50 years passed before the genius of Brunelleschi’s dome would be conceived and executed

• These people had Faith!– In themselves, and in the march of progress

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And our lessons…

• Move forward with solutions as we can conceive them…

• Have confidence in our ability to surmount the challenges…

• Remember that the benefit in our efforts is in the quiet, unobtrusive implementation of standards

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The Core, the Core, the Core

• The Dublin Core is the dominant standard for cross disciplinary resource discovery metadata on the Internet

• The semantics of the Core have not changed since DC-3

• Stable and useful since 1996• Standardized and widely accepted

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And More, and more, and more

• More communities participating• More extensions to register• More government and supra-national adoption• More languages• More application profiles • More protocols to accommodate• More documentation needed to make it clearer and

easier to deploy• More connections to other standards

• This richness is evidence of success and a challenge to interoperability

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Many Challenges - Protocols are moving targets

• HTML XHTML• RDF and RDF

Schemas• XML• XML Schema

• OAI• OAI PMH• Open URLs• RSS• DAML/OIL

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More Standards

• MARC and its many variants

• IEEE-LOM/IMS• SCORM• FGDC• EAD

• MPEG• TEI• XRML• ODRML• Ontologies• METS and MODS

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Standards creation as an act of faith