Lifecycle Metadata for Digital Objects

1
Lifecycle Metadata for Digital Objects

• November 1, 2004
• Descriptive Metadata
• Modeling the World

2
Descriptive metadata for what?

• WWW now seen as the ONE place to find everything
• Descriptive metadata provides
• Unique identification for a resource
• Information permitting evaluation/selection of a
  resource
• Information describing all essential properties

3
WWW How to find things

• What does search mean on the WWW?
• How to support its multiple purposes?
• Failure of search engines (problems of scale)
• Failure of HTML metatags (spamming)
• Solution
• local expert cataloging (providing access points)
• remote free-text searching (inferring access
  points)
• Dublin Core and its limitations
• Warwick Framework and RDF
• Universal Semantic Web

4
Some metadata examples

• Individual objects (Dublin Core and its
  derivatives)
• Multimedia and/or complex objects (METS/MPEG21)
• Books and other chunks of information (MARC)
• Finding aids (EAD)

5
Semantic Web

• Berners-Lees vision for the Web basically
  machine-understandable metadata about meaning for
  everything on the Web
• http//www.semaview.com/d/Semweb_Illustrated.pdf

6
Aside on cataloging

• Cataloging systems as static relationships
  remained tacit
• Classification systems
• Controlled vocabularies
• Name authorities
• New methods look to AI and logical relations,
  ultimately to automated methods
• All can be implemented in XML as namespaces

7
Ontologies

• Like previous classification systems, they are
  being built by hand
• General (Cyc) and domain-specific
• Ontologies establish a joint terminology between
  members of a community of interest
• Ontologies specify domain knowledge in terms of
  formal logic
• Ontologies will be used to guide extraction of
  semantic content from texts (and perhaps
  automatic generation of metadata)

8
Topic Maps

• Representation of information using topics,
  associations, and occurrences
• Note how this triples representation fits well
  with RDF
• An (older) ISO standard ISO/IEC 132502003
• Related to ontologies and mind maps designed to
  map semantic regions

9
Web Services

• How to provide processing services over the WWW
  XML and HTTP infrastructure passing remote
  procedure calls
• UDDI (Universal Description Discovery and
  Information) is the registry of services
• WSDL (Web Services Description Language) allows
  advertisement of services (in XML, of course)
  in the UDDI registry
• SOAP (Simple Object Access Protocol) is the XML
  wrapper for requests sent to services
• Example DC metadata registry http//dublincore.o
  rg/dcregistry/

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Example RSS feeds

• Rich Site Summary lets syndicated partners know
  about updates on a website
• Modules
• Dublin Core
• Syndication
• Content
• Many others to make up a full metadata set for
  managing online resources as though the WWW were
  a library (minus, of course, preservation etc.)

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Does what we know fit into this?

• DC and derivatives are aimed at the single object
  (though not always used for it) and are
  frequently used in WWW contexts (cf. Warwick
  Framework/RDF namespaces)
• EAD describes descriptions of aggregate chunks of
  information (chunked in terms of series or
  collections) but can describe single objects
• MARC/MODS describes aggregate chunks of
  information (chunked in the form of books)
• METS and MPEG21 are frames for multimedia objects

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Granularity

• Granularity governs the level at which metadata
  can be descriptive
• Metadata granularity tends to be finer for
  digital objects
• Digital objects cannot be managed without
  individual granularity (thank you David Bearman)

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EAD Describing descriptions

• What is a finding aid?
• Describing a finding aid so it can be searched
• Expanding a finding aid to accommodate individual
  granularity
• Is it efficient to drill down through a finding
  aid to individual objects?
• Can EAD be searched from the bottom up?

14
MARC Chunked packages

• International Standard Bibliographic Description
  (ISBD) as parent of MARC, TEI
• MODS User-friendly MARC? subset of MARC elements
  (19), language-based tags
• MARC as descriptive metadata
• Bibliographical detail for the work
• Bibliographical detail for the specific instance
  of the work (cf. FRBR)
• Places the work within one or many classificatory
  systems (ontologies, controlled vocabularies,
  authority lists)
• But alas! Not consistent!

15
METS Multimedia/Multiversion

• METS developed to express archival bond among
  objects related to one another as a single work
  (cf. FRBR, Warwick Framework, RDF)
• Reflects concerns of digital librarians who want
  to make a wide range of versions available
• Standard form
• General descriptive metadata for package
• Object link
• Object type
• Specific descriptive metadata set

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What about the single object?

• Is Dublin Core enough? Outdated?
• What about derivatives?
• Qualified DC, DC profiles
• Australian elements
• 5015.2 elements
• Why describe the single object?
• Who will describe at the object level?
• Zillions of archivists?
• Authors?
• Automatic analysis (ontology-driven)?