W3C home > Mailing lists > Public > www-tag@w3.org > July 2007

Re: Terminology Question concerning Web Architecture and Linked Data

From: Dan Connolly <connolly@w3.org>
Date: Tue, 10 Jul 2007 12:08:08 -0500
To: Chris Bizer <chris@bizer.de>
Cc: www-tag@w3.org, semantic-web@w3.org, Linking Open Data <linking-open-data@simile.mit.edu>
Message-Id: <1184087288.20170.47.camel@pav>

On Sat, 2007-07-07 at 14:43 +0200, Chris Bizer wrote:
> Hi all,
> 
> Richard Cyganiak, Tom Heath and me are currently writing a tutorial on how 
> to publish Linked Data [1] on the Web and ran into some terminology 
> questions concerning Web Architecture.
> 
> Here is the problem statement together with an example: Within the Linking 
> Open Data community project [2] different data sources (URI owners) publish 
> information about Tim Berners-Lee using different HTTP URIs:
> 
> 1. DBpedia: http://dbpedia.org/resource/Tim_Berners-Lee
> 2. Hannover DBLP Server: 
> http://dblp.l3s.de/d2r/resource/authors/Tim_Berners-Lee
> 3. Berlin DBLP Server: 
> http://www4.wiwiss.fu-berlin.de/dblp/resource/person/100007
> 4. RDF Book Mashup: 
> http://www4.wiwiss.fu-berlin.de/bookmashup/persons/Tim+Berners-Lee
> 
> The first 3 data sources follow the W3C TAG "Dereferencing HTTP URIs" 
> finding [3]

draft, in progress...

>  and redirect via HTTP 303 to documents describing Tim 
> Berners-Lee when the URIs are dereferenced over the Web. Therefore, the URIs 
> identify Tim Berners-Lee as a non-information resource.

Rather: therefore the do not claim that these URIs
identify information resources.

The lack of a claim is very different from the negation of a claim.

>  This redirect also 
> supports HTTP content negotiation and leads to HTML as well as RDF 
> descriptions of Tim.
> 
> 5. Tim also publishes a FOAF profile in which he assigns the URI 
> http://www.w3.org/People/Berners-Lee/card#i to himself.
> 
> Question 1: According to the terminology of the Architecture of the WWW 
> document [4] are all these URIs aliases for the same non-information 
> resource (our current view) or are they referring to different resources? 

They are aliases: the URI owners say so and nothing in webarch
says otherwise.

> Does the TAG finding "On Linking Alternative Representations To Enable 
> Discovery And Publishing " [5] about generic and specific resources apply 
> here, meaning that the URIs 1,2,3,5 refer to different specific 
> non-information resources that are related to one generic non-information 
> resource?

No, I don't think so.

The generic resource finding is mostly about information resources, I
think.

> Question 2: When the URIs are dreferenced they provide quite different 
> information about Tim, which reflects the knowledge and the opinion of the 
> specific URI owner about him. Within our tutorial we need to talk about this 
> information and therefore need a term to refer to a concept that can be 
> described as "information provided by a specific URI owner about a 
> non-information resource", for example Tim. Depending on the answer to 
> question 1, what would be the correct Web Architecture term to refer to this 
> concept? Or is such a term missing?

I don't think the TAG has established a term for that.

(It sounds a bit like log:semantics from N3, but I'm not quite sure
http://www.w3.org/2000/10/swap/doc/Reach )

> Question 3: Depending on the answer to question 1, is it correct to use 
> owl:sameAs [6] to state that http://www.w3.org/People/Berners-Lee/card#i and 
> http://dbpedia.org/resource/Tim_Berners-Lee refer to the same thing as it is 
> done in Tim's profile.

Yes...

That's sort of a circular question. It's correct because Tim says
it's correct, and he owns that name.

> Any clarifications on these question would be highly welcomed.
> 
> Cheers
> 
> Chris
> 
> 
> [1] http://www.w3.org/DesignIssues/LinkedData.html
> [2] 
> http://esw.w3.org/topic/SweoIG/TaskForces/CommunityProjects/LinkingOpenData
> [3] http://www.w3.org/2001/tag/doc/httpRange-14/2007-05-31/HttpRange-14
> [4] http://www.w3.org/TR/webarch/
> [5] http://www.w3.org/2001/tag/doc/alternatives-discovery.html
> [6] http://www.w3.org/TR/owl-ref/#sameAs-def
> 
> --
> Chris Bizer
> Freie Universit├Ąt Berlin
> +49 30 838 54057
> chris@bizer.de
> www.bizer.de 
> 
-- 
Dan Connolly, W3C http://www.w3.org/People/Connolly/
Received on Tuesday, 10 July 2007 17:08:21 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Thursday, 26 April 2012 12:47:46 GMT