DBpedia Blog

DBpedia version 3.2 released including the new DBpedia Ontology

Summary

we are happy to announce the release of DBpedia version 3.2.

The new knowledge base has been extracted from the October 2008 Wikipedia dumps. Compared to the last release, the new knowledge base provides three mayor improvements:

1. DBpedia Ontology

DBpedia now features a shallow, cross-domain ontology, which has been manually created based on the most commonly used infoboxes within Wikipedia. The ontology currently covers over 170 classes which form a subsumption hierarchy and have 940 properties. The ontology is instanciated by a new infobox data extraction method which is based on hand-generated mappings of Wikipedia infoboxes to the DBpedia ontology. The mappings define fine-granular rules on how to parse infobox values. The mappings also adjust weaknesses in the Wikipedia infobox system, like having different infoboxes for the same class (currently 350 Wikipedia templates are mapped to 170 ontology classes), using different property names for the same property (currently 2350 template properties are mapped to 940 ontology properties), and not having clearly defined datatypes for properties. Therefore, the instance data within the infobox ontology is much cleaner and better structured than the infobox data within the DBpedia infobox dataset which is generated using the old infobox extraction code. The DBpedia Ontology currently contains about 882.000 instances.

More information about the ontology is found at http://wiki.dbpedia.org/Ontology

2. RDF Links to Freebase

Freebase is an open-license database which provides data about million of things from various domains. Freebase has recently released an Linked Data interface to their content. As there is a big overlap between DBpedia and Freebase, we have added 2.4 million RDF links to DBpedia pointing at the corresponding things in Freebase. These links can be used to smush and fuse data about a thing from DBpedia and Freebase.

For more information about the Freebase links see
http://blog.dbpedia.org/2008/11/15/dbpedia-is-now-interlinked-with-freebase-links-to-opencyc-updated/

3. Cleaner Abstacts

Within the old DBpedia dataset it occurred that the abstracts for different languages contained Wikpedia markup and other strange characters. For the 3.2 release, we have improved DBpedia’s abstract extraction code which results in much cleaner abstracts that can safely be displayed in user interfaces.

Access the new DBpedia knowledge base 

The new DBpedia release can be downloaded from:

http://wiki.dbpedia.org/Downloads32

and is also available via the DBpedia SPARQL endpoint at

http://dbpedia.org/sparql

and via DBpedia’s Linked Data interface. Example URIs:

http://dbpedia.org/resource/Berlin
http://dbpedia.org/page/Oliver_Stone

Lots of thanks to everybody who contributed to the Dbpedia 3.2 release!

Especially:

1. Georgi Kobilarov (Freie Universität Berlin) who designed and implemented the new infobox extraction framework.
2. Anja Jentsch (Freie Universität Berlin) who contributed to implementing the new extraction framework and wrote the infobox to ontology class mappings.
3. Paul Kreis (Freie Universität Berlin) who improved the datatype extraction code.
4. Andreas Schultz (Freie Universität Berlin) for generating the Freebase to DBpedia RDF links.
5. Everybody at OpenLink Software for hosting DBpedia on a Virtuoso server and for providing the statistics about the new Dbpedia knowledge base.

Have fun with the new DBpedia knowledge base!