Re: publicly available RDF* datasets

Hi!

 > I don't know if anyone has attempted it yet, but an RDFStar version 
of Wikidata could be very interesting. There are a lot of per-factoid 
annotations.

I had a look at it while building YAGO 4. There are two challenges with 
Wikidata mapping to RDF*:

1. Different statements could have the same "main triple". For example, 
Wikidata could have a first statement stating that JohnDoe has been the 
president of Bar between 1996 and 2002 and an other statement stating 
he has been the president of Bar between 2008 and 2012. A simple RDF* 
encoding would lead to:
<JohnDoe presidentOf Bar> startDate 1996 .
<JohnDoe presidentOf Bar> endDate 2002 .
<JohnDoe presidentOf Bar> startDate 2008 .
<JohnDoe presidentOf Bar> endDate 2012 .
This encoding might lead query and reasoning systems to assume that 
JohnDoe has been the president of Bar between 1996 and 2012, fact that 
is wrong.

2. Wikidata contains "deprecated" statements that should not be 
asserted as facts. For example, we could have in an RDF*-like syntax:
<JohnDoe presidentOf Bar> prov:wasDerivedFrom Source ; wikibase:rank 
wikibase:Deprecated .
In this case the fact "JohnDoe presidentOf Bar" should not be asserted 
by itself.
So, a RDF*-Wikidata would only be valid in "SA" mode and not in "PG" 
mode.

Thomas


Le mar. 1 sept. 2020 à 10:54, Dan Brickley <danbri@google.com> a 
écrit :
> On Tue, 1 Sep 2020 at 08:53, Jeen Broekstra <jb@metaphacts.com> wrote:
>> Hi folks,
>> 
>> Does anyone have any pointers to publicly available datasets that 
>> make use of RDF*?
>> 
>> I am aware that Yago 4 makes some limited use of RDF* annotations, 
>> but I was curious if there are any other good examples that people 
>> use for testing, demonstration, or even production use.
> 
> I don't know if anyone has attempted it yet, but an RDFStar version 
> of Wikidata could be very interesting. There are a lot of per-factoid 
> annotations.
> 
> https://www.mediawiki.org/wiki/Wikibase/DataModel
> 
>> Regards,
>> 
>> Jeen
>> --
>> Dr Jeen Broekstra (he, him)
>> principal software engineer
>> 
>> jb@metaphacts.com
>> www.metaphacts.com
>> 
>>

Received on Tuesday, 1 September 2020 13:43:00 UTC