FRBR in RDF

Ian Davis (ian.davis@talis.com)

Technical Lead, Research Group

Talis Information Ltd.

What is the FRBR?

• For us non-librarians...
• "Functional Requirements for Bibliographic Records"
• Published by the IFLA
• Describes an entity-relation model for bibliographic information
• Provides a common model to enable interoperability
• http://www.ifla.org/VII/s13/frbr/frbr.htm

How Did I Get Involved?

• Joined Research Group at Talis in June to work on Semantic Web
• Thought I'd better learn some of this library stuff
• Found a rich, well-thought out model - FRBR
• First thought - "this feels like a good fit with RDF"
• No published schema but several people thinking about it.
• Richard Newman (http://www.holygoat.co.uk/) had most complete version

Richard's Original Schema

• Started in July 2004
• Based on "casting down" abstract notions from FRBR into specific domains like musical recordings
• FRBR has several duplicated relationships between entities
• e.g. reproduction can apply between manifestation and manifestations, manifestation and item, item and item
• Ended up with stupidly long names like isAManifestationReproductionOfManifestation
• Work stalled

Cleaning The Schema

• Richard had focussed on detailed modelling of constraints
• Properties like isAReferentialSuccessorToExpression
• Very precise - lets domains and ranges infer concrete types
• Together we felt the need for a simpler version
• Split into two parts:
  • core
  • extended
• Given a stable, persitant home at http://vocab.org

FRBR Core Schema

• http://purl.org/vocab/frbr/core
• Models the core entities (Work, Expression, Place, Person etc.)
• General entity relationships (realization, complement, part etc.)
• Focus on simple expression of FRBR
• No entity attributes yet... but they belong in this schema

FRBR Extended Schema

• http://purl.org/vocab/frbr/extended
• Models refinements of entities (ReferentialWork, AutonomousExpression etc)
• Specific typed entity relationships (complementsWork, hasPartWork etc.)
• Focus on typed expression of FRBR
• Still under heavy development

Group 1 Entities

• Endeavour - Any of the products of artistic or creative endeavour.
• Not a FRBR entity but a superclass for the following group 1 entities:
• Work - An abstract notion of an artistic or intellectual creation.
• Expression - A realization of a single work usually in a physical form.
• Manifestation - The physical embodiment of one or more expressions.
• Item An exemplar of a single manifestation.

Group 1 Entities

Group 2 Entities

• ResponsibleEntity - One responsible for the creation, production, distribution or maintenance of artistic or creative content.
• Again not a FRBR entity but a superclass for the following group 2 entities:
• CorporateBody - An organization or group of individuals and/or other organizations.
• Person - A living or dead individual.

Group 3 Entities

• Subject - Something that may serve as the subject of a work.
• Again not a FRBR entity but a superclass for the following group 3 entities:
• Concept - An abstract idea or notion
• Object - A tangible or material thing.
• Event - An action or occurrence.
• Place - A location.

Properties

• Naming follows convention
• XXX has property with value YYY
• e.g. foo has realization with value bar
• Most properties are paired with an inverse
  • realization/realizationOf - relate works and expressions
  • embodiment/embodimentOf - relate expressions and manifestations
  • exemplar/exemplarOf - relate manifestations and items
• Synthetic superclasses used for some property ranges and domains:
  • creator/creatorOf - relate works and ResonsibleEntities

What's Missing?

• Entity attributes (title, date, context, medium etc)
• Looking to Dublin Core, PRISM, MODS etc.
• Forms - what form a work has
• e.g. Biography, ArtisticWork, ScholarlyWork, LiteraryWork, LegalWork, News

Abbreviated Example

@prefix frbr: <http://purl.org/vocab/frbr/core#> .
@prefix dc: <http://purl.org/dc/elements/1.1/> .

<http://www.imdb.com/title/tt0245712/>
  a frbr:Work;
  dc:title "Amores Perros"@es ;
  dc:title "Love's a Bitch"@en ;
  frbr:subject <#Mexico_City> ;
  frbr:realization <#amores-perros> ;

<#amores-perros>
  a rbib:MotionPicture ;
  dc:creator "Alejandro González Iñárritu" ;
  frbr:embodiment <#amores-perros-dvd> .

<#amores-perros-dvd>
  a rbib:DVD ;
  dc:date "2000" .

Schema Design

• Lucky - started with a good model!
• Use of OWL-DL to provide constraints
• e.g. Works cannot be Expressions
• Grounding with respect to other schemas
• SKOS to document schema

Documentation

• Generated by XSLT! - no RDF templating language
• Requires RDF/XML to follow regular patterns
• Permission from IFLA to reuse content from report - but were commercial constraints
• Experimenting with paraphrasing OWL constraints
• A class: A frbr:Manifestation is something that, amongst other things, is a frbr:Endeavour but is not a frbr:Work and is not a frbr:Expression and is not a frbr:Item
• A property: Having a frbr:complement implies being something that, amongst other things, is a frbr:Work or a frbr:Expression

Paraphrase Generation

• <rdfs:subClassOf rdf:resource="http://purl.org/vocab/frbr/core#Endeavour"/>
• <owl:disjointWith rdf:resource="http://purl.org/vocab/frbr/core#Work"/>
• <owl:disjointWith rdf:resource="http://purl.org/vocab/frbr/core#Expression"/>
• <owl:disjointWith rdf:resource="http://purl.org/vocab/frbr/core#Item"/>
• A frbr:Manifestation is something that...

Paraphrase Generation

• <rdfs:subClassOf rdf:resource="http://purl.org/vocab/frbr/core#Endeavour"/>
• <owl:disjointWith rdf:resource="http://purl.org/vocab/frbr/core#Work"/>
• <owl:disjointWith rdf:resource="http://purl.org/vocab/frbr/core#Expression"/>
• <owl:disjointWith rdf:resource="http://purl.org/vocab/frbr/core#Item"/>
• A frbr:Manifestation is something that, amongst other things, ...
• Remember the open world assumption!

Paraphrase Generation

• <rdfs:subClassOf rdf:resource="http://purl.org/vocab/frbr/core#Endeavour"/>
• <owl:disjointWith rdf:resource="http://purl.org/vocab/frbr/core#Work"/>
• <owl:disjointWith rdf:resource="http://purl.org/vocab/frbr/core#Expression"/>
• <owl:disjointWith rdf:resource="http://purl.org/vocab/frbr/core#Item"/>
• A frbr:Manifestation is something that, amongst other things, is a frbr:Endeavour

Paraphrase Generation

• <rdfs:subClassOf rdf:resource="http://purl.org/vocab/frbr/core#Endeavour"/>
• <owl:disjointWith rdf:resource="http://purl.org/vocab/frbr/core#Work"/>
• <owl:disjointWith rdf:resource="http://purl.org/vocab/frbr/core#Expression"/>
• <owl:disjointWith rdf:resource="http://purl.org/vocab/frbr/core#Item"/>
• A frbr:Manifestation is something that, amongst other things, is a frbr:Endeavour but is not a frbr:Work

Paraphrase Generation

• <rdfs:subClassOf rdf:resource="http://purl.org/vocab/frbr/core#Endeavour"/>
• <owl:disjointWith rdf:resource="http://purl.org/vocab/frbr/core#Work"/>
• <owl:disjointWith rdf:resource="http://purl.org/vocab/frbr/core#Expression"/>
• <owl:disjointWith rdf:resource="http://purl.org/vocab/frbr/core#Item"/>
• A frbr:Manifestation is something that, amongst other things, is a frbr:Endeavour but is not a frbr:Work and is not a frbr:Expression

Paraphrase Generation

• <rdfs:subClassOf rdf:resource="http://purl.org/vocab/frbr/core#Endeavour"/>
• <owl:disjointWith rdf:resource="http://purl.org/vocab/frbr/core#Work"/>
• <owl:disjointWith rdf:resource="http://purl.org/vocab/frbr/core#Expression"/>
• <owl:disjointWith rdf:resource="http://purl.org/vocab/frbr/core#Item"/>
• A frbr:Manifestation is something that, amongst other things, is a frbr:Endeavour but is not a frbr:Work and is not a frbr:Expression and is not a frbr:Item

Grounding Schemas

• Learnt that it is very important to relate ones work to others
• Puts work in context
• Makes the schema part of the "web" of schemas
• RDF enables this naturally...
• subClassOf/subPropertyOf - is-a relationships
• equivalentClass/equivalentProperty - stronger equivalence

Specific Groundings

• FOAF
  • frbr:Person equivalentClass to foaf:Person
  • CorporateBody equivalentClass to union of foaf:Organization and foaf:Group
• Geo
  • frbr:Object subClassOf geo:SpatialThing
  • frbr:Place subClassOf geo:SpatialThing
• OWL Time
  • frbr:Event subClassOf owltime:Event
• SKOS
  • frbr:Concept subClassOf skos:Concept

Relevancy Beyond Bibliographic Domain

• Model appears to fit with other domains
• Web Architecture
• Notion of resource identified by a URI, corresponds to FRBR Work
• Resources have representations, corresponding to Expressions
• Web browser negotiates encodings etc, corresponds to Manifestation
• Actual bits sent correspond to Item
• Known FRBR issue with electronic Items...

Dublin Core

• New activity to assign domains and ranges to core terms
• FRBR fits well in many cases:

Dublin Core 2

Issues

• Most issues are with abstract nature of FRBR
  • What constitutes a different Work? Different creators? What about collaborative works?
  • Is a periodical a Work?
  • Quite far removed from citation requirements, e.g. chapters, articles etc
• Issue whether Items can be digital.
  • FRBR report suggests they must be physical
• Complexity of modelling typed relationships in RDF + OWL
  • Remember isAManifestationReproductionOfManifestation
  • Needed so domain and range can be set explicitly to Manifestation rather than more general Endeavour
  • Alternate is multiple namespaces: frbrman:reproduction, frbritem:reproduction!

Thanks!

• Contacting us...
• Ian Davis, (ian.davis@talis.com)
• Richard Newman (holygoat@gmail.com)
• Bruce D'Arcus (bdarcus@gmail.com)
• Mailing list at http://holygoat.co.uk/mailman/listinfo/sw-bib_holygoat.co.uk
• Specs at http://vocab.org/frbr/core and http://vocab.org/frbr/extended
• These slides will be at http://research.talis.com/2005/frbr-dc2005