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Re: DBpedia-based RDF dumps for Wikidata

From: Dimitris Kontokostas <kontokostas@informatik.uni-leipzig.de>
Date: Fri, 15 May 2015 17:50:24 +0300
Message-ID: <CA+u4+a3VorQ8XqKwoULiBCbTd992mrxQ75eHVqJj3CgS3oqWog@mail.gmail.com>
To: Michael Brunnbauer <brunni@netestate.de>
Cc: "semantic-web@w3.org" <semantic-web@w3.org>
Hello Michael and thank you for the feedback

On Fri, May 15, 2015 at 5:27 PM, Michael Brunnbauer <brunni@netestate.de>
wrote:

>
> Hello Dimitris,
>
> I recently started working with the Wikidata RDF dump and what struck me as
> great improvement over DBpedia is the missing separation of the ontology:
> Wikidata things can be individuals, classes or subclasses so I expect much
> more rdf:type and rdfs:subclassOf statements to reason with than with the
> comparatively small DBpedia ontology.
>
> So these mappings are a bit disappointing for me:
>
>  "P31": {"rdf:type": "$getDBpediaClass"}
>  "P279":{"rdfs:subClassOf": "$getDBpediaClass"} (DBpedia things can be
> subclasses now?)
>

For the latter mapping (rdfs:subClassOf) we were kind of hesitant weather
to include it or not. We decide to do but in the released dumps it is not
yet separated as a standalone dataset.
The only reason we allowed it was to use it as feedback for the DBpedia
ontology. With post-processing we can translate things to DBpedia classes.


> I guess $getDBpediaClass will not return a match very often.


We got ~ 8M type statements using this mapping


> Are there any
> plans to massively expand the DBpedia ontology and maybe make the DBpedia
> classes real citizens of DBpedia?
>

I am not sure I understand you suggestion exactly. We already have
equivalent class links to Wikidata and the following as an open task
https://github.com/dbpedia/ontology-tracker/issues/5
Would something like this cover you or are you against standalone
ontologies in general?
Also note that DBpedia comprises of 125 wikipedia language editions,
Wikimedia Commons and now Wikidata, each as a separate dataset.
Thus, it is hard to make a class a real citizen in each dataset

Best,
Dimitris


>
> Regards,
>
> Michael Brunnbauer
>
> On Fri, May 15, 2015 at 01:28:51PM +0300, Dimitris Kontokostas wrote:
> > Dear all,
> >
> > Following up on the early prototype we announced earlier [1] we are happy
> > to announce a consolidated Wikidata RDF dump based on DBpedia.
> > (Disclaimer: this work is not related or affiliated with the official
> > Wikidata RDF dumps)
> >
> > We provide:
> >  * sample data for preview http://wikidata.dbpedia.org/downloads/sample/
> >  * a complete dump with over 1 Billion triples:
> > http://wikidata.dbpedia.org/downloads/20150330/
> >  * a  SPARQL endpoint: http://wikidata.dbpedia.org/sparql
> >  * a Linked Data interface: http://wikidata.dbpedia.org/resource/Q586
> >
> > Using the wikidata dump from March we were able to retrieve more that 1B
> > triples, 8.5M typed things according to the DBpedia ontology along with
> 48M
> > transitive types, 6.4M coordinates and 1.5M depictions. A complete report
> > for this effort can be found here:
> > http://svn.aksw.org/papers/2015/ISWC_Wikidata2DBpedia/public.pdf
> >
> > The extraction code is now fully integrated in the DBpedia Information
> > Extraction Framework.
> >
> > We are eagerly waiting for your feedback and your help in improving the
> > DBpedia to Wikidata mapping coverage
> > http://mappings.dbpedia.org/server/ontology/wikidata/missing/
> >
> > Best,
> >
> > Ali Ismayilov, Dimitris Kontokostas, Sören Auer, Jens Lehmann, Sebastian
> > Hellmann
> >
> > [1]
> >
> http://www.mail-archive.com/dbpedia-discussion%40lists.sourceforge.net/msg06936.html
> >
> > --
> > Dimitris Kontokostas
> > Department of Computer Science, University of Leipzig & DBpedia
> Association
> > Projects: http://dbpedia.org, http://http://aligned-project.eu
> > Homepage:http://aksw.org/DimitrisKontokostas
> > Research Group: http://aksw.org
>
> --
> ++  Michael Brunnbauer
> ++  netEstate GmbH
> ++  Geisenhausener Straße 11a
> ++  81379 München
> ++  Tel +49 89 32 19 77 80
> ++  Fax +49 89 32 19 77 89
> ++  E-Mail brunni@netestate.de
> ++  http://www.netestate.de/
> ++
> ++  Sitz: München, HRB Nr.142452 (Handelsregister B München)
> ++  USt-IdNr. DE221033342
> ++  Geschäftsführer: Michael Brunnbauer, Franz Brunnbauer
> ++  Prokurist: Dipl. Kfm. (Univ.) Markus Hendel
>



-- 
Dimitris Kontokostas
Department of Computer Science, University of Leipzig & DBpedia Association
Projects: http://dbpedia.org, http://http://aligned-project.eu
Homepage:http://aksw.org/DimitrisKontokostas
Research Group: http://aksw.org
Received on Friday, 15 May 2015 14:51:19 UTC

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