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Authority control, new library standards, and the Semantic Web. Gordon Dunsire Presented to the Authority Control Interest Group (ACIG) meeting, ALA Annual, New Orleans, 26 June 2011. Overview. RDA, FRBR, FRAD and authority control Extending authority control concepts to data linking
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Authority control, new library standards, and the Semantic Web Gordon Dunsire Presented to the Authority Control Interest Group (ACIG) meeting, ALA Annual, New Orleans, 26 June 2011
Overview • RDA, FRBR, FRAD and authority control • Extending authority control concepts to data linking • Linked data and the Semantic Web
RDA implementation scenario 1: Relational/object-oriented database structure FRAD FRBR
Bibliographic record: 12345 Name authority record: 8765 Title: Cataloguing is fun! Heading: MacDonald, Mary Author: Mary MacDonald 8765 Place of birth: 9876 Edinburgh Content type: text 1234 LCSH authority record: 5432 Media type: microform 5432 Heading: Cataloging LCSH: 5432 Cataloging See also: 65443 Books RDA content type record: 1234 Term: text Definition: Content expressed through a form of notation for language intended to be perceived visually. ISBD media type record: 5432 Term: microform Definition: Media used to store reduced-size images, not readable to the human eye, and designed for use with a device such as a microfilm or microfiche reader.
Bibliographic record: 12345 Name authority record: 8765 Title: Cataloguing is fun! Heading: MacDonald, Mary Author: 8765 Place of birth: 9876 Content type: 1234 Media type: 5432 Stop! Ambiguous: link not safe. LCSH: 5432 Identifier: ok to link. 9876 9876 Country Country 4567 4567 8765 9876 9876 8765 Heading Heading Name Name “Edinburgh” “Edinburgh” “MacDonald, Mary” “MacDonald, Mary” 8765 8765 8765 Place of birth Place of birth Place of birth 9876 9876 9876 12345 12345 12345 Author Author Author 8765 8765 8765
Linked data is not a new idea! • It extends concepts of authority control • “Preferred” labels • Create/maintain once; link many times • Re-use of metadata • More than one “attribute” associated with a “heading” • E.g. Place of birth of person with name heading • Concepts can be applied to authority records • As well as bibliographic description records • Full extension leads to “record” dis-aggregation • All “records” in bibliographic control systems
Linked data and RDF • Resource Description Framework (RDF) • Designed for machine-processing of metadata at global scale (Semantic Web) • 24/7/365 • Trillions of operations per second • Everything must be dis-ambiguated • Machines are dumb • Simplicity helps! • Machine-readable identifiers
RDF triple • Metadata expressed as “atomic” statements • A simple, single, irreducible statement • The title of this book is “Cataloguing is fun!” • Constructed in 3 parts • “Triple” • The title of this book is “Cataloguing is fun!” • Subject of the statement = Subject: This book • Nature of the statement = Predicate: has title • Value of the statement = Object: “Cataloguing is fun!” • This book – has title – “Cataloguing is fun!” • subject – predicate - object
Identifiers • Need unambiguous way of identifying each part of the triple for efficient machine-processing • Human labels (“This book”, “has title”) no good • Same thing, different labels; different things, same label • Exploit the utility of the URL • Machine-readable, regular syntax, unambiguous • Uniform Resource Identifier (URI)
Uniform Resource Identifier • Can be any unique combination of numbers and letters • No intrinsic meaning; it’s just an identifier • Can look like a URL • http://iflastandards.info/ns/isbd/elements/P1001 • But does not lead to a Web page (in principle ...) • RDF requires the subject and predicate of triple to be URIs • Object can be a URI, or a literal string (“Cataloguing is fun!”)
RDF properties • Predicates are called properties in RDF • “Verbal” part of the metadata statement • E.g. “A has author B”, “B has heading ...” • Properties link specific instances of two things • A = a specific book, B = a specific person • ... = a specific label, character string, annotation • => a “literal” • Properties are the links in linked data, the pathways through the Semantic Web to human-readable metadata
Labels, global identifiers, linked data • Headings can be managed in the same way as other controlled vocabularies • They are all RDF labels • Global identifiers (URIs) and RDF allow distributed authority control • But without need to copy and maintain in local systems • Different labels for the same thing can be linked, and a chain can link a label to a resource • Its all linked data ...
Thank you • gordon@gordondunsire.com • Sponsors • ALA • Cataloging & Classification Quarterly • MARCIVE, Inc.