Re: Managing Co-reference (Was: A Semantic Elephant?)

Salut Yves

Yves Raimond a écrit :
> Hello!
>
>   
>> Agreed. I do not want to be picky about that: SW is Web, and errors are
>> life.
>> Just there is no need to use owl:sameAs in many cases, and at least in LOD
>> large projects, this can be avoided easily.
>>     
>
> Sorry to jump in the middle of this discussion, but I don't
> particularly agree with that. They are plenty of cases where they
> can't really be avoided, even in LOD large projects.
> For example, http://dbtune.org/jamendo/artist/5 and
> http://zitgist.com/music/artist/0781a3f3-645c-45d1-a84f-76b4e4decf6d
> identify the same artist. One of them in the Jamendo database, and one
> of them in Musicbrainz.
>   
See my previous message. It all depends on what you mean by "the same 
artist" ...
> Both databases hold *really* different type of information about these
> artists. Musicbrainz holds detailed editorial information (regardless
> of their publication in the Jamendo Creative Commons platform),
> information about the members of this band and their birth dates, etc.
> Jamendo holds actual audio items, and also a set of tags for each of them.
>   
In this case, maybe you have the chance to have completely orthogonal 
descriptions, IOW different "facets".
Unclear
> As an URI is not only an identifier but also a way to access a
> specific representation, how could I use a single URI in this case? In
> other words, how would I avoid the owl:sameAs between the two?
>   
This is the core issue. From a purely declarative viewpoint, owl:sameAs 
entails that representations are merged and you can't separate any more 
what is coming from where. It's a semantic equivalent of thermodynamics 
2nd principle. I'm not sure that "a URI is not only an identifier but 
also a way to access a specific representation" is an affirmation which 
holds in a linked data universe.
> Different data sources make different claims about similar thing, and
> we need both a way to access these claims and to keep the cross-source
> identity. I think owl:sameAs is quite a nice way of doing that.
>   

You are no more native speaker than I am :)
But you seem to use "same" and "similar" indifferently. My point is that 
"same" and "similar" are similar, but not the same.

Bernard

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*Bernard Vatant
*Knowledge Engineering
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Received on Thursday, 15 May 2008 13:11:45 UTC