Transcript Evolving MARC 21 for the future Rebecca Guenther CCS Forum, ALA Annual July 10, 2009

Evolving MARC 21 for the future
Rebecca Guenther
CCS Forum, ALA Annual
July 10, 2009
Overview of presentation
The current MARC environment
 Successes of MARC
 Moving to XML
 RDA and FRBR experimentation
 Linked data
 Issues to resolve

Credits
Sally McCallum for some slide
content
 John Espley for FRBR
implementation
 Clay Redding for Linked Data
content

What is MARC 21?

A syntax defined by an international standard for
communications with 2 expressions:






Classic MARC (MARC 2709)
MARCXML
A data element set defined by content
designation and semantics
Institutions do not store “MARC 21”, as it is a
communications format
Many data elements are defined by external
content rules; a common misperception is that it
is tied to AACR2
A set of 5 formats for different purposes:
Bibliographic, Authority, Holdings, Classification,
Community Information
The current MARC
environment






Billions of rich descriptive records in MARC
systems
Many national formats have been harmonized
with MARC 21
Integrated library systems that support MARC
bibliographic, authority and holdings format for
different functions
Wide sharing of records for 30+ years
OCLC is a major source of records
MARC records are being reused (sometimes
converted) and repackaged
MARC successes

Can carry data formulated by different
cataloging rules and conventions





Multiple descriptive rules, different principles and
models
Different subject thesauri
Multiple languages and scripts
Cooperation in record exchange has resulted in
widespread use and cost savings
Richness of MARC records supports multifaceted
retrieval


Coded data
Parsed data
Problems with MARC







MARC 2709 syntax problems
Limitation of available fields, subfields,
indicator values, etc.
Redundant data (fixed vs. variable fields)
Controlled values embedded in the
standard
Ability to link
Limits to extensibility
Lack of explicit hierarchical levels
Some progress…
MARCXML
 Definition of $u, $w and $0 for
linking
 Definition of $2 to specify source of
controlled values
 Exploration into use of URIs
 MODS

Streamlining MARC 21
into the future

Take advantage of XML



Develop simpler (but compatible)
alternatives


MODS
Allow for interoperability with different XML
metadata schemas


Increasingly use MARC 21 in an XML structure
Take advantage of freely available XML tools
Assemble coordinated set of tools
Provide continuity with current data

Provide flexible transition options
MARCXML






MARCXML uses the MARC data element set in
an XML syntax
Lossless roundtrip conversions
Simple flexible XML schema, no need to
change when MARC 21 changes
Interoperability with different XML schemes by
taking advantage of free XML tools
Collaborative use of metadata for access
(e.g.OAI)
Continuity with current data and flexible
transition options
Example: http://lccn.loc.gov/2004012412
MARC 21 evolution to XML
More use of MARCXML
Transition to exchange in MARCXML
instead of MARC 2709
 Take advantage of namespaces to
allow for extensions (e.g. technical
metadata)
 Potential to extend with new
attributes or subfield markers

Other related XML
schemas: MODS








Eliminates some of the problems with MARC
(e.g. lack of tags/subfield codes)
More user-friendly (uses language tags)
Repackages redundant data elements into one
Can carry hierarchical data
Less tied to cataloging rules
Highly compatible with MARC but simpler,
although retaining some richness
Widely implemented especially for digital
projects
Governed by Editorial Committee
Example: http://lccn.loc.gov/2004012412/mods
Other related XML
schemas: METS


METS
 A container/information package
 Wrapper for MARCXML and MODS descriptions
 Allows for additional technical and
preservation metadata
 Enables tracking of actions on the metadata
itself
LC is exploring a native XML database for search
and retrieval bringing together records from
many internal systems using
MODS/MARCXML/METS
Experimentation with RDA,
FRBR and RDF



MARC changes to accommodate RDA
MODS changes to accommodate RDA
FRBR experimentation



VTLS has implemented a FRBR based system using
MARC
Other systems are looking at migrating to reflect entityrelationship models
Semantic web experiments



Modeling MODS and MADS as RDF
Modeling MARC as RDF
See Martha Yee’s article in Information Technoclogy and
Libraries (v. 28, no. 2, June 2009)
Example of FRBR
implementation of MARC: VTLS
Single database can have FRBR and non-FRBR
records
System is “aware” of FRBR record level and
changes displays as needed
Display of FRBR records are in tree structure
Local level fields have values of W, E, and M to
indicate type of FRBR record
001 and 004 used as linking tags
Experimentation with
“Linked data”





Library of Congress Authorities & Vocabularies service:
http://id.loc.gov
Allows both human-oriented and programmatic access to
LC-promulgated authorities and vocabularies
Actionable URIs associated with concepts
First offering is Library of Congress Subject Headings, but
more to come: e.g. Thesaurus of Graphic Materials, ISO
639-2, MARC code lists, etc
Advantages




Facilitate development and maintenance process for
vocabularies
Expose vocabularies to wider communities
Offer bulk downloads
Example:
http://id.loc.gov/authorities/sh85049843
Issues to resolve for
bibliographic formats









Actionable vs. descriptive
Parsed vs. text
Controlled/access vs. transcribed
Codes vs. words
Library vs. non-library traditions
My model vs. your model
Stability vs. change
Basic retrieval vs. scholar retrieval
Cost of change
How do we move forward?



Continue RDA/FRBR implementation changes
Transition to XML for exchange (syntax)
Evolve MARC 21 (data element set)






Analyze successes that need to be carried over into a
streamlined MARC
Consider MODS features to be incorporated
Consider use of MARC 21 for different cataloging
rules, models and traditions, not just RDA
Consider cost implications
Assure continuity with current data
Evolution will take some time and will be in
phases
Comments?

Tell us what you think:
[email protected]
or
 [email protected]
