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Re: 'parallel properties' reference?

From: Stéphane Corlosquet <scorlosquet@gmail.com>
Date: Tue, 25 Oct 2011 12:06:50 -0400
Message-ID: <CAGR+nnEGbMoSF4sFrpty7YXhkO-S94imDAcjUOBKDFgOT=Cz_w@mail.gmail.com>
To: Sandro Hawke <sandro@w3.org>
Cc: Jonathan Rees <jar@creativecommons.org>, www-tag@w3.org, Richard Cyganiak <richard@cyganiak.de>
On Mon, Oct 24, 2011 at 4:13 PM, Sandro Hawke <sandro@w3.org> wrote:

> On Mon, 2011-10-24 at 16:04 -0400, Jonathan Rees wrote:
> > I'm looking for something explaining how 'parallel properties' work,
> > mentioned here:
> >
> > http://www.w3.org/2001/tag/2011/06/07-minutes.html
> >
> > Tim: Parallel properties - in the open graph protocol on Facebook you
> > get a page about a movie. The RDF references "" (empty URI) is of type
> > "Movie" etc... Sandro says - since they use their own namespace ogp:
> > then we know that ogp: usage means that the referent is the principal
> > subject of the resource referenced.
>
> This is what I wrote, introducing the concept (in a larger context):
>
> http://decentralyze.com/2010/11/10/simplified-rdf/
>
> Not many people expressed interest in this work, so it's become a low
> priority for me.    I still think it's a good idea, though.


Richard Cyganiak and I also talked about a similar idea at the RDF Next
Steps workshop in June last year. The idea was to clone vocabularies and
allow the cloned classes/props to be used directly with the document as
domain, then fix things at the RDF level. We never got around making this
idea public, but for the records, here it is below... surely not as polished
as Sandro's simplified RDF though.

HTH,

Steph.

---------- Forwarded message ----------
From: Stéphane Corlosquet <scorlosquet@gmail.com>
Date: Mon, Jun 28, 2010 at 1:35 PM
Subject: RDF information resources indirections
To: Richard Cyganiak <richard@cyganiak.de>


Richard,

I've pasted below the RDF snippet of the discussion we had in Palo Alto.
During the design phase of the RDF/RDFa in Drupal 7, I thought about how we
could make this as easy as possible for Drupal users, but given the lack of
applied best practice, I've left it out of core. The way this is handled in
the separate contributed RDF module is similar to this approach below, i.e.
create a new RDF resource by appending #this to the web page URI, link the
two with foaf:primaryTopic (or foaf:account for the user profile page,
that's the only exception in core), and then, on a per field basis, offer
the option to choose whether the value of a field applies to the webpage or
the information resource. However the last bit is the tricky part, not on
the implementation level, but for the user to decide which subject a
property should describe, the web page (e.g. dc:title) or the information
resource (foaf:name). Sometimes, the label for the page (Homepage of Tom
Cruise) is different from the label of the information resource (Tom
Cruise). I dread explaining the difference between a web page and an
information resource to the Drupal community or any lay person for that
matter. If we can have something easier to use like below, we would push
this awkward, complex situation on the hands of the semweb experts, which
would leave the newbies, early adopters and users with an easier time to
join the Semantic Web band wagon. Although I'm sure there will be some
resistance from the RDF purists, this is something which would benefit the
Linked Data crowd at large.

Steph.


# my FOAF file today
<#me> a foaf:Person ;
      foaf:homepage <> .

=================

# new approach, using imaginary FOAFx terms (cloned FOAF)
<> a foaf:Document, foafx:Person ;
   foafx:name "scor" ;
   dc:title "Homepage of scor" .


# FOAFx vocabulary specification using new indirection vocabulary (ind)
foafx:Person a rdfs:Class, ind:DocumentClass ;
             ind:referencedClass foaf:Person ; # determines the type of the
indirected RDF information resource
             ind:indirectionProperty foaf:homepage ; # used to link page to
RDF Information resource blank node
             rdfs:subClass foaf:Document;
             owl:disjointWith foaf:Person .

foafx:name a rdf:Property, ind:DocumentProperty ;
             ind:referencedProperty foaf:name . # determines the property of
the indirected RDF information resource



# triples inferred from the semantics of ind:indirectionProperty and
ind:referencedClass
_:p1 a foaf:Person ;
     foaf:name "scor" ;
     foaf:homepage <> .
Received on Tuesday, 25 October 2011 16:07:50 GMT

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