- 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>
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 Universität 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 UTC