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Re: Ordnance Survey data as Linked Data (RE: How do you deprecate URIs? Re: OWL-DL and linked data)

From: Kingsley Idehen <kidehen@openlinksw.com>
Date: Sat, 12 Jul 2008 13:37:28 -0700
Message-ID: <48791608.8020700@openlinksw.com>
To: afraz.jaffri@tiscali.co.uk
CC: public-lod@w3.org, semantic-web@w3.org

Afraz Jaffri wrote:
> We are pleased to announce a Linked Data site for the Ordnance Survey, 
> available at:
>
> http://os.rkbexplorer.com
>
> with links from over 8000 URIs to Geonames URIs. Take 'Hampshire' as 
> an example:
>   
Afraz,
> http://os.rkbexplorer.com/description/osr7000000000017765
>
>   
kidehen$ curl -I -H "Accept: application/rdf+xml" 
http://os.rkbexplorer.com/description/osr7000000000017765
HTTP/1.1 406 Not Acceptable
Date: Sat, 12 Jul 2008 20:31:35 GMT
Server: Apache/2.0.52 (Red Hat)
X-Powered-By: PHP/4.3.9
Content-Type: text/html; charset=UTF-8
Connection: close

Why no 303 or use of <link rel="[relavant-predicate]" .../>  so that 
User Agents can locate 
<http://os.rkbexplorer.com/data/osr7000000000017765> .

My issues are summarized here:

http://demo.openlinksw.com/rdfbrowser2/?uri%5B%5D=http%3A%2F%2Fos.rkbexplorer.com%2Fdescription%2Fosr7000000000017765&uri%5B%5D=http%3A%2F%2Fos.rkbexplorer.com%2Fdata%2Fosr7000000000017765&

Kingsley
> It might also be the right time, with all the owl:sameAs discussion, 
> to practically demonstrate how our coreference system works. In the 
> above example the link created is between 'Hampshire the county' from 
> the OS and 'Hampshire the second order administrative division' from 
> Geonames. We do not know if these two entities are exactly the same, 
> so 
> instead of using owl:sameAs we use our own coref:duplicate predicate.
>
> One of the features of our system is that knowledge about coreference 
> is separated from the knowledge of the actual entity. In the RDF for 
> the above URI at http://os.rkbexplorer.com/data/osr7000000000017765 
> you 
> will find:
>
> <coref:coreferenceData rdf:resource="http://os.rkbexplorer.
> com/crs/osr7000000000017765"/>
>
> Resolving this URI will give you a 'bundle' containing the duplicates:
>
> <coref:Bundle>
>     <coref:canon rdf:resource="http://os.rkbexplorer.
> com/id/osr7000000000017765"/>
>     <coref:duplicate rdf:resource="http://os.rkbexplorer.
> com/id/osr7000000000017765" />
>     <coref:duplicate rdf:resource="http://sws.geonames.org/2647554/"/>
>     <coref:lastUpdated>2008-07-10 11:39:44</coref:lastUpdated>
>   </coref:Bundle>
>
> As you can see one URI is chosen as the canonical URI to use. The 
> separation of coreference means, to a limited extent, that the 
> context 
> of duplication can be preserved. If I wanted to say that under some 
> other context there were other URIs that were deemed to be the same 
> then I can simply create another bundle with another <coref:
> coreferenceData> predicate in the RDF for the entity. Of course, the 
> question of how to show the context is yet to be solved...
>
> There may be some errors in the equivalences. All feedback is 
> greatfully received :)
>
> In relation to another question about how owl:sameAs is currently 
> being used, there are some examples in our LDOW paper:
> http://eprints.ecs.soton.ac.uk/15181/
>
> in particular http://dbpedia.org/resource/Welsh and http://dbpedia.
> org/resource/Lilac 
>
> Regards,
> Afraz
>
>
>   
>> -----Original Message-----
>> From: public-lod-request@w3.org [mailto:public-lod-request@w3.org] 
>>     
> On 
>   
>> Behalf Of Harry Halpin
>> Sent: 09 July 2008 10:55
>> To: Hugh Glaser
>> Cc: Bijan Parsia; Peter Ansell; semantic-web at W3C; public-lod@w3.
>>     
> org
>   
>> Subject: Re: How do you deprecate URIs? Re: OWL-DL and linked data
>>
>>
>> Hugh Glaser wrote:
>>     
>>> Thanks guys, a really interesting and important discussion.
>>> However, after the last couple of postings I have the feeling I 
>>>       
> may
>   
>> agree
>>     
>>> with both of you.
>>> Is that possible?
>>>
>>>       
>> Bijan et. al. are right about the semantics of owl:sameAs, but as 
>>     
> I've 
>   
>> said before, I think that something weaker needs to be coined
>> ("lod:equivalentTo") that states that two URIs refer to the same 
>>     
> thing 
>   
>> but that any semantic entailments *may* not hold (i.e. user beware).
>> That's a dangerous thing, I agree, but it seems to be what the 
>>     
> Linked 
>   
>> Data community needs and what's happening organically in the wild 
>>     
> with 
>   
>> the (ab)use of owl:sameAs.
>>
>>     
>>> Hugh
>>>
>>>
>>>       
>
>
>
> __________________________________________________________
>
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> __________________________________________________________
>
>
>
>
>
> __________________________________________________________
>
> Free games for a wet weekend - http://www.tiscali.co.uk/play
> __________________________________________________________
>
>
>
>
>   


-- 


Regards,

Kingsley Idehen	      Weblog: http://www.openlinksw.com/blog/~kidehen
President & CEO 
OpenLink Software     Web: http://www.openlinksw.com
Received on Saturday, 12 July 2008 20:38:15 UTC

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