RDF Schema for Thesauri

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RDF Schema for Thesauri

• Phil Cross
• University of Bristol, UK

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Background DESIRE II Project

• Development of Quality Subject Gateways
• Importance of indexing and classification
• Report on conceptual relationships for encoding
  thesauri and classification systems RDF Schema
• http//ilrt.org/discovery/2001/01/rdf-thes/

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Why Use RDF?

• Importance as a fundamental layer of the semantic
  Web
• Standard for encoding metadata
• Intended as a means of expressing relationships
  between objects concepts and terms
• Extensible

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What is RDF?

• Statement about identifiable objects
• "The author of the page is Ora"
• triple(author, page, Ora)

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An RDF Statement
page
Ora
author
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In XML/RDF
ltrdfdescription rdfabout"http//ilrt.org/page.h
tml"gt ltauthor rdfresource"http//www.w3.org/staf
fId/85740"/gt lt/rdfdescriptiongt
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Or
ltrdfdescription rdfabout"http//ilrt.org/page.h
tml"gt ltauthorgt Ora lt/authorgt lt/rdfdescriptiongt
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Adding further links
Ora
forename
page
Ora
author
email
ora_at_w3.org
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What is RDF Schema?

• Defines types of resources in a particular domain
• Declares their properties/attributes
• rdfsClass rdfsProperty
• rdfssubClassOf rdfssubPropertyOf

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Thesaurus schema

• Main classes
• Concept
• Term
• Main properties
• broaderConcept
• relatedConcept
• indicator

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Concepts and Terms
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Relationships Between Concepts

• broaderConcept
• If A broaderConcept B
• then assume B narrowerConcept A
• relatedConcept
• If A relatedConcept B
• then assume B relatedConcept A

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Classes

• Concept
• Term
• ScopeNote
• TermUsageValue

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Properties

• broaderConcept
• narrowerConcept
• indicator
• conceptCode
• scope
• lang
• termUsage

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What can it be used for?

• Standard method for encoding thesaurus data
• Tested with developing RDF query standards
• Four thesauri on SOSIG
• MeSH thesaurus on Bristol BioMED
• LIMBER project

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What can it be used for?

• Cross-mapping
• New Concept properties
• fullyEquivalent, broaderEquivalent, etc.?
• Multilinguality
• Classification

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Classification Schema
330
rdfvalue
rdfvalue
deweynotations/id67
Economics
deweycaptions/id097
class notation
classlang
classcaption
Dewey Decimal
eng
deweyconcepts/id511
classschemeName
classbroaderConcept
eng
deweyconcepts/id233
classschemeName
classlang
classcaption
class notation
Dewey Decimal
rdfvalue
deweycaptions/id213
Financial economics
deweynotations/id68
332
rdfvalue
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References

• Thesaurus schema http//ilrt.org/discovery/2001/
  01/rdf-thes/
• SOSIG thesaurus http//www.sosig.ac.uk/roads/cgi-
  bin/thesaurus.pl
• LIMBER project http//jodi.ecs.soton.ac.uk/Artic
  les/v01/i08/Miller/
• email phil.cross_at_bristol.ac.uk

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Autoclassification?
Lund classifier
0.9
weighting
method
Concep_indicator_15
indicative_term
indicated_concept
Term_56
Concept_78
notation
schemeName
value
DDC
economics
330