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Re: missing bit of RDF for XML people

From: Frank Manola <fmanola@acm.org>
Date: Thu, 03 Feb 2005 09:09:49 -0500
Message-ID: <420230AD.9030104@acm.org>
To: Karl Dubost <karl@w3.org>
CC: www-rdf-interest@w3.org

You don't necessarily need a *blank* predicate.  You just need a 
"standard" predicate (standard for somebody!) that means "is related to" 
(in some way that you haven't identified further).  Using this, you'd 
write something like:

   subject        predicate          object

  country  - ex:isRelatedTo --> "Canada"
  country  - ex:isRelatedTo --> city  - ex:isRelatedTo --> "Montréal"
  country  - ex:isRelatedTo --> city  - ex:isRelatedTo --> "Toronto"
  country  - ex:isRelatedTo --> city  - ex:isRelatedTo -->
  "Vancouver"

You could use variations of that theme to represent the "different" 
blank predicates you have.  Alternatively, you could have a special 
vocabulary for (partially) translating XML, like ex:containedValue and 
ex:containedElement (which would retain some information that simple 
blank predicates would lose).

--Frank

Karl Dubost wrote:
> 
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> Hash: SHA1
> 
> Hi,
> 
> this is all naive but it's in my mind and writing the email helps me to 
> push it out, and let me sleep :p
> 
> It's on the usual stance of XML People saying yes there is semantics in 
> XML.
> 
> <country>
>     Canada
>     <city>Montréal</city>
>     <city>Toronto</city>
>     <city>Vancouver</city>
> </country>
> 
> XML People: You can see that the hierarchical organization and the name 
> of elements is the semantics.
> RDF People: No, the semantics is not "machine explicit". (subject, 
> predicate, object).
> 
> What RDF people are saying is that the predicate is not given, except in 
> the specification which describes the semantics of each elements of the 
> XML file.
> 
> So I thought let's write something without thinking about writing good RDF.
> 
>  subject        predicate          object
> 
> country  - (blank_predicate1) --> "Canada"
> country  - (blank_predicate2) --> city  - (blank_predicate3) --> "Montréal"
> country  - (blank_predicate2) --> city  - (blank_predicate3) --> "Toronto"
> country  - (blank_predicate2) --> city  - (blank_predicate3) --> 
> "Vancouver"
> 
> A blank predicate would be something, there's a relation between these 
> two things, but I don't yet how to describe it, just I know that it 
> exists and I know that between these type of things, the relation is 
> always the same unknown type.
> 
> Exactly like we say, there is this thing but I don't have a name for it 
> (blank node)
> 
> Except that this is not possible in RDF, there's no such things as blank 
> predicate. But maybe all of that is very naive, and doesn't make sense 
> at all. :))))
> 
Received on Thursday, 3 February 2005 14:02:41 GMT

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