What could be made better with regard to DBpedia's ontology?

1. Advancing the DBpedia Ontology
Presentation DBpedia Community Meeting
Trinity College, Dublin
February 9, 2015
Gerard Kuys
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2. What is the problem with the DBpedia ontology?
l Grown out of the need to accommodate extracted resources and typing those
l Basic structure organised mostly along the dimensions:
l Agents, Roles and Activities
l Place, but not Time
l Someone’s working area reduced to the spatial dimension
l Instruments (Device and the like)
l Works
l As an organised collection of Types, the DBpedia ontology has more of a partial and
rather haphazard Taxonomy than of a consistent encyclopedic description of knowledge
domains
l Editors and mappers add classes and properties for single-purpose actions, and for single-
language mappings (if for mappings at all)
l DBpedia basically is an extraction mechanism, however, being also a hub in the Linked-
Data cloud, it could assume functions that cannot rely on just extracting Wikipedia data any
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3. A statement of flaws
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4. What is definitely NOT the problem with the DBpedia
ontology?
l Being a Wikipedia wrapping mechanism, it represents a common understanding of things
that is deemed by a community to be relevant to be documented
l It allows for all kinds of variations over language editions
l It allows for enriching language editions with information from other language editions

5. What should be the course of action?
l The DBpedia Ontology should remain a community-driven structure for encyclopedic
knowledge
l However, we want more, and better, structure for the ontology
l At the same time, we do not want to impose a canonical model of the world
l Nor do we want to disrupt existing mappings
l Therefore, we should aim at a process of gradually improving the existing framework and
offer non-intrusive ways of ‘remapping mappings’
l This might break some eggs, but, please, not all eggs at the same time ;-)
As a basis for every course of action, we should take stock of DBpedia classes and how they
are being used across language editions
*How many classes with no individuals
* Classes added for reference, not because extracted notions need to be accommodated,
l but because the DBpedia ontology can be used as a kind of 'universal reference'
l Use tools like RDFUnit to bring to light obvious deficiencies
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And embark on a process of quality improvement indeed
l Prepare a set of guidelines on how to use and how to extend the DBpedia ontology

6. Approaches suggested so far
Procedure:
A DBpedia Committee responsible for improvement of the Dbpedia Ontology, monitoring
changes and publisher guidelines (Dimitris Kontokostas)
Style:
Open, bottom-up collaborative ontology development
l (Agnieszka Ławrynowicz)
Actions to be taken:
Mapping to upper ontologies, implementing more of owl:disjointWith
l (Daniel Fleischhacker)
l Pruning the classes’ tree, implement corrections found by the RDF Unit tool
l (Peter Patel-Schneider, Dimitris Kontokostas)
l Using the Universal Decimal Classification with its auxiliary tables as a ‘connected
structural backbone’
l (Gerard Kuys)
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7. Connecting fields of knowledge
l Is it really necessary to pull external mappings into the DBpedia ontology?
l If not, how to connect best? (More than one single answer allowed)
l How about using the wealth of links in Wikidata? We’re connected already!
l In my view, DBpedia should remain a stronghold of the encyclopedic approach:
l Not very deep, not the newest details and insights
l In stead of that, document the connection to adjacent phenomena, and the nature of that
connection
l How about a matrix with ‘objects of knowledge’ as one dimension, and ‘disciplines of
knowledge’ as the other? This type of approach is what makes the UDC so interesting!
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