DBpedia ontology evolution

This sunburst shows the hierarchical ontology of the 2014 and 2015 version of DBpedia. The new version has 736 classes while the previous 684. In order to build the visualization we used .nt file data downloadable from the DBpedia web site (2014, 2015). We converted them in json format using the ntToJson.py script.

In order to obtain a correct hierarchy, some changes has been made to the original files:

• 2014 VERSION: There are two cases of multiple inheritance:

  • Mountain:

  <http://dbpedia.org/ontology/Mountain> <http://www.w3.org/2000/01/rdf-schema#subClassOf> <http://dbpedia.org/ontology/NaturalPlace> .
  <http://dbpedia.org/ontology/Mountain> <http://www.w3.org/2000/01/rdf-schema#subClassOf> <http://dbpedia.org/ontology/Place> .
  

  • Library:

  <http://dbpedia.org/ontology/Library> <http://www.w3.org/2000/01/rdf-schema#subClassOf> <http://dbpedia.org/ontology/Building> .
  <http://dbpedia.org/ontology/Library> <http://www.w3.org/2000/01/rdf-schema#subClassOf> <http://dbpedia.org/ontology/EducationalInstitution> .
  

  In both cases, the second subClassOf triple has been removed in order to create a perfect hierarchical structure.

  Strange case:

  <http://dbpedia.org/ontology/PublicService> <http://www.w3.org/2000/01/rdf-schema#subClassOf> <http://dbpedia.org/ontology/> .
  <http://dbpedia.org/ontology/PublicServiceInput> <http://www.w3.org/2000/01/rdf-schema#subClassOf> <http://dbpedia.org/ontology/PublicService> .
  <http://dbpedia.org/ontology/PublicServiceOutput> <http://www.w3.org/2000/01/rdf-schema#subClassOf> <http://dbpedia.org/ontology/PublicService> .
  

  The first triple has been change with

  <http://dbpedia.org/ontology/PublicService> <http://www.w3.org/2000/01/rdf-schema#subClassOf> <http://www.w3.org/2002/07/owl#Thing> . 
  

• 2015 VERSION:

  • Mountain has only the triple:

  <http://dbpedia.org/ontology/Mountain> <http://www.w3.org/2000/01/rdf-schema#subClassOf> <http://dbpedia.org/ontology/NaturalPlace> .
  

  • Library still has:

  <http://dbpedia.org/ontology/Library> <http://www.w3.org/2000/01/rdf-schema#subClassOf> <http://dbpedia.org/ontology/Building> .
  <http://dbpedia.org/ontology/Library> <http://www.w3.org/2000/01/rdf-schema#subClassOf> <http://dbpedia.org/ontology/EducationalInstitution> .
  

  The second triple of Library has been removed.