Representation of the Data Documentation Initiative using
Semantic Web TechnologiesWorkshop on Semantic Statistics
12.09.2011 – 16.09.2011
Thomas Bosch(research associate, GESIS Leibniz Institute for the Social Sciences)
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Agenda
• Use Cases
• Take-aways and Discussion
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Publish and Link DDI Data and Metadata
Linking Open Data cloud diagram, by Richard Cyganiak and Anja Jentzsch. http://lod-cloud.net/
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Semantic Queries• What kinds of problems can be solved?• Queries on multiple, distributed and merged DDI instances• Formulation using DDI domain concepts
questionScheme
?question
?question
?question
contains
SELECT ?questionWHERE { questionScheme contains ?question. }
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Integration of Other Ontologies
• Domain ontologies' classes can relate to similar concepts of external ontologies• Reasoner may use additional semantic information
Other Ontologies
DDI Domain
Ontology
(Question) (Question)
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DDI Consistency Check
• Definition of 'consistency'• OWL reasoning techniques
• Class consistency• Global consistency
• Global consistency of DDI ontology Global consistency of DDI data model
Concept Hierarchy
text + html(superClassOf)
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Variable Concept
ConceptReference
Concept
SimilarConcept
Difference SimilarConceptReference
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Concept Hierarchy
Variable
Concept
hasConcept
subConceptOf
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DDI Elements‘ Comparability
CodeVariable
Grade_USA
Grade_Germany
1.0
A
hasCode
hasCode
subClassOf
subClassOf
subClassOf
subClassOf
• Necessary conditions (equality, inequality, similarity, …)
ReferencesOtherMaterial
Citation
DCElements
Title Creator
ExternalURLReference
RelatedToReference
Relationship
...
…
URN
...…
type
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ReferencesOtherMaterial
Citation
DCElements
Title Creator
ExternalURLReference
RelatedToReference
Relationship
...
…
URN
...…
type
Drawbacks:
• type• complex data model• no intuitive semantics• bibliographic citation
limits• ensure reusability?
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Semantic References
ReferencingPublication Publication
referencesPublication
Variable
subClassOf
publicationReferencedByX
Creator
ID
URLDateTitle
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Agenda
• Use Cases
• Take-aways and Discussion
http://ddiandsemanticweb.blogspot.com
LOD Cloud
Concept Hierarchies
Consistency
Comparability
Use Cases
SPARQL Queries
Ontology Integration
References