MARC21 Update UK Cataloguing & Indexing Standards Forum 13

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Transcript MARC21 Update UK Cataloguing & Indexing Standards Forum 13

Publishing
the British National Bibliography
as
Linked Open Data
Corine Deliot
Metadata Standards Analyst
British Library
CIG Event
Birmingham, 25 November 2013
© The British Library Board 2013
Overview
• Motivations and approach
• The modelling process and the data model
• Technical process: from MARC 21 to RDF
• Linking to external datasets
• Outcomes – datasets/platform/access
• Plans for future developments
• Use of the BNB data
• Benefits
• Challenges
www.bl.uk
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Motivations
• Publishing our data for others to re-use
• Looking beyond library audiences
• Taking part in the Linked Data conversation
www.bl.uk
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How?
• Pragmatic, bottom-up approach
• Using existing staff
• Building on existing skills
• Using existing tools as much as possible
www.bl.uk
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Why BNB?
• General bibliography - not a
unique institutional catalogue
• Consistent format - over 60 years
• Size & range of content - 3
million records on all subjects in many
languages
• Control of metadata –
publishable as CC0.
www.bl.uk
© Waldir/ Wikimedia Commons/ CC BY-SA-3.0
Usage terms: http://creativecommons.org/licenses/by-sa/3.0/
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The modelling process (I)
• identify our objects of interest, i.e. what does the
MARC record says about “things in the world”
 e.g. Bibliographic resources, people, organizations,
places, subjects, etc.
• Assign URIs to identify these objects of interests
www.bl.uk
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URIs: Things to think about
• Create our own URIs or use existing ones?
 e.g. http://viaf.org/viaf/96994048
http://id.loc.gov/authorities/names/n78095332
• Create opaque or transparent URIs?
• e.g. http://viaf.org/viaf/96994048 or
http://dbpedia.org/resource/William_Shakespeare
• What pattern?
 URI pattern guidance from the UK Cabinet Office
“Designing URI Sets for the UK Public Sector”
• Create valid, i.e. syntax conformant URIs
www.bl.uk
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URI patterns
• http://bnb.data.bl.uk/id/resource/{control-number}
• http://bnb.data.bl.uk/id/resource/{BNB-number}
• http://bnb.data.bl.uk/id/person/{person-name}
• http://bnb.data.bl.uk/id/organization/{organization-name}
• http://bnb.data.bl.uk/id/concept/lcsh/{topic}
• http://bnb.data.bl.uk/id/concept/ddc/{editionnumber}/{dewey-number}
www.bl.uk
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URI patterns
• http://bnb.data.bl.uk/id/resource/008043929
• http://bnb.data.bl.uk/doc/resource/008043929
• http://bnb.data.bl.uk/doc/resource/008043929.rdf
• http://bnb.data.bl.uk/doc/resource/008043929.ttl
• http://bnb.data.bl.uk/doc/resource/008043929.json
• http://bnb.data.bl.uk/doc/resource/008043929.html
www.bl.uk
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The modelling process (II)
• Describe these objects of interest, i.e. use classes
• and how they relate to each other, i.e. use properties
Use classes and properties from existing RDF
vocabularies
Define our own classes and properties when required;
documented in the British Library Terms RDF schema
www.bl.uk
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RDF Vocabularies
• Bibliographic Ontology
• Org: an Organisation Ontology
• Bio: a Vocabulary for
Biographical Information
• OWL
• British Library Terms
• RDA
• Dublin Core
• RDF
• Event Ontology
• RDF Schema
• FOAF: Friend of a Friend
• SKOS
• ISBD
• WGS84 Geo Positioning
www.bl.uk
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RDF Vocabularies
• Bibliographic Resource




Dublin Core
Bibliographic Ontology
ISBD
British Library Terms
• Event
 Event Ontology
 British Library Terms
• Person/Organization
 FOAF: Friend of a Friend
 Bio: a Vocabulary for
Biographical Information
 Org: an Organisation
Ontology
 RDA
• Place
 WGS84 Geo Positioning
• Concept
• RDF
• RDF Schema
• OWL
www.bl.uk
 SKOS
 British Library Terms
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The British Library Terms RDF Schema
@prefix blt:<http://www.bl.uk/schemas/bibliographic/blterms#> .
• Existing property not quite right (e.g. not granular enough)
 e.g. dcterms:identifier vs blt:bnb
www.bl.uk
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The British Library Terms RDF Schema
@prefix blt:<http://www.bl.uk/schemas/bibliographic/blterms#> .
Property or class required by specific feature of the model
 e.g. blt:publication and blt:PublicationEvent (rdfs:subclass
of event:Event)
www.bl.uk
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The British Library Terms RDF Schema
@prefix blt:<http://www.bl.uk/schemas/bibliographic/blterms#> .
For pragmatic reasons, e.g. facilitate searching and navigating
through the graph
 e.g. blt:TopicLCSH and blt:TopicDDC
 e.g. blt:hasCreated owl:inverseOf dcterms:creator
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The BNB data model - Books
www.bl.uk
http://www.bl.uk/bibliographic/pdfs/bldatamodelbook.pdf
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Data Model Features (I): the Bibliographic
Resource
www.bl.uk
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Data Model Features (II): Publication as an event
@prefix dc:<http://purl.org/dc/elements/1.1/> .
@prefix dcterms:<http://purl.org/dc/terms> .
“Publisher” ;
<BibResource> dc:publisher
dcterms:issued
“Date” ;
?:placeOfPublication
“Place” .
Usual
approach
@prefix blt:<http://www.bl.uk/schemas/bibliographic/blterms#> .
@prefix event:<http://purl.org/NET/c4dm/event.owl#> .
<BibResource>
blt:publication
<PublicationEvent> event:place
event:agent
event:time
www.bl.uk
<PublicationEvent> .
<Place> ;
Event-based
<Publisher> ;
approach
<Year> .
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Data model features (III)
• Birth and death are modelled as biographical events
• extensive use of foaf:focus to relate “things in the world”
(e.g. people, organizations, places) to their SKOS concepts.
 e.g. “London”, the capital of England and the UK as a single
“thing in the world” may be the “focus” of multiple concepts
belonging to different concept schemes, e.g. thesauri (LCSH,
Rameau, etc.)
<Thing-as-Concept> foaf:focus <Thing in the World> .
http://efoundations.typepad.com/efoundations/2011/09/thing
s-their-conceptualisations-skos-foaffocus-modellingchoices.html by Pete Johnston
www.bl.uk
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MARC to RDF Conversion Workflow
Full BNB
MARC21
File
Select records
Convert to precomposed UTF-8
Normalise for
improved
matching &
transforms
MARC
Pre-Processing
Create BL URIs
and add external
URIs by
matching
Process
• Selection
• Character set conversion
• Pre-processing
• URI generation
• Data transformation
• Create & load triples
• Produce VoiD descriptions
Transform to
RDF/XML using
XSLT
Tools
• Catalogue Bridge Utilities
• MARC Global/MARC Report
http://www.marcofquality.com/
• Jena Eyeball
http://jena.sourceforge.net/Eyeball/
www.bl.uk
BNB RDF/
XML file
Generate RDF
Triple Dump
Load to BL
Downloads page
Load to Linked
Data Platform
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Linking to external sources (I)
To give our data broader
context we linked to:
• General resources:
• GeoNames
• Lexvo
• RDF Book
Mashup
• Library resources:
•
•
•
•
www.bl.uk
LCSH
VIAF
Dewey.info
MARC language
and country
codes
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Linking to external sources (II)
Techniques included:
• Automatic generation from
record data
• Auto text match with linked data
dumps
• Crosswalk matching for coded
data
www.bl.uk
© Silverspoon/ Wikimedia Commons/ CC BY-SA-3.0
Usage terms: http://creativecommons.org/licenses/bysa/3.0/
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Outcomes
• Two datasets – Books and Serials - and their VoID descriptions,
accessible at:
• BNB Linked data platform: http://bnb.data.bl.uk
• SPARQL endpoint: http://bnb.data.bl.uk/sparql
• SPARQL editor: http://bnb.data.bl.uk/flint
• Bulk downloads: http://www.bl.uk/bibliographic/download.html
 Updated monthly
 Serializations available:
RDF/XML, N-Triples
www.bl.uk
“Linking Open Data cloud diagram, by Richard Cyganiak and
Anja Jentzsch. http://lod-cloud.net/”
Usage terms: http://creativecommons.org/licenses/by-sa/3.0/
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www.bl.uk
http://bnb.data.bl.uk
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www.bl.uk
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www.bl.uk
http://bnb.data.bl.uk/flint
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www.bl.uk
http://www.bl.uk/bibliographic/download.html
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Platform change
• 2011 - initial Talis platform
• 2013 – data migration to TSO platform
http://www.tso.co.uk/our-expertise/technology/openup-platform
 Tendering process
 Migration of data and services over a couple of months
www.bl.uk
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Plans for Future Developments
• Refine and extend the model
• Investigate frbr-ization
• Link to other external sources
• Geonames at city level
• ISNI, LC/NACO, DBpedia
• DNB bibliographic resources
• Expand scope beyond current BNB
• Improve developer support
www.bl.uk
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Use of the BNB data
• Statistics
 e.g. Number of hits on the SPARQL endpoint
 e.g. Number of downloads on the BL webpage
• BNB data used in pilot projects
 e.g. Linked Open BNB data used as test data for a semantic
search demonstrator.
• Anecdotal evidence
• Use is difficult to assess; part and parcel of the data being
open and available for all to use.
www.bl.uk
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Benefits of Linked Open Data
• We have learnt a lot about the practical aspects of working
with linked data.
• The data model got some attention.
 Re-used by Danish Bibliographic Centre (DBC)
 Stanford Linked Data Workshop Technology Plan
““…ensure resulting model retains the BL’s high-level focus and its
web derived, transparent structure for representing facts about
people, organizations, places, events, and topics”
• LOD raised the Library’s profile internally and externally
• LOD helped us focus our legacy data enhancement
activities
www.bl.uk
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Challenges
Converting MARC data into RDF!
• Publication event approach: transforming transcribed text into data
• URI creation from string
 may result in duplication
 changes over time may also produce duplication.
• Legacy data issues
 e.g. inconsistency of the data
 e.g. cataloguers using inadequate input tools for diacritics
• This is (relatively) new, nobody has all the answers
www.bl.uk
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For further information
http://bnb.data.bl.uk
http://www.bl.uk/bibliographic/datafree.html
Thank you.
Questions?
[email protected]
http://twitter.com/#!/BLMetadata
www.bl.uk
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