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tracing statement origin (was Re: I have a trouble with The RDF Model)

From: Gabe Beged-Dov <begeddov@jfinity.com>
Date: Sun, 26 Nov 2000 20:58:14 -0800
Message-ID: <3A21E9E6.373A800@jfinity.com>
To: Stefan Decker <stefan@db.stanford.edu>
CC: pat hayes <phayes@ai.uwf.edu>, RDF-Logic <www-rdf-logic@w3.org>, "www-rdf-interest@w3.org" <www-rdf-interest@w3.org>
I am CC'ing rdf-interest since this seems like more of a model issue
more than a logic issue. It is very related to a whole bunch of
threads that have been active on rdf-interest recently.

As reference, here are the entries in this thread so far on rdf-logic:


Stefan Decker wrote:

<snip />

> The open question is how to represent the source in RDF.
> The result of an earlier discussion was to represent it by reification.
> (See: http://www-db.stanford.edu/~stefan/updates.html for links to the
> earlier discussion.).
> The language has not changed  -  I used  ([Bush, wonThe, Election] at
> Electoral College) as an abbreviation for
> {[Bush, wonThe, Election])
>   [id1, type, statement]
>   [id1, subject, Bush]
>   [id1, predicate, wonThe]
>   [id1, predicate, Election]
> [id1, at, Electoral College]
> }
> (although I still would vote to extend the RDF model)

I don't see why the "at" predicate is necessary for associating the
source document with the reified statement resource. You label this
resource with "id1". Do you mean this as a fragment identifier that is
expanded to "uri_standing_in_for_electoral_college#id1" ? 

I think the RDF syntax already allows both a document level and a
container level way to trace the source of an occurence of a
triple/statement. The document level tracing is provided by the URI of
the riefied statement resource. The container level (equivalent to
rdf:Description) tracing is provided by the URI of the Bag that is
generated to trace all the statements that occurred in that Bag's
syntactic occurrence. Here is a fully labelled syntax fragment in a
source document:

document name: http://electoralCollege.org/results.rdf
<rdf:Description rdf:bagID="bag1" rdf:about="bush">
   <wonThe rdf:ID="id1">Election</wonThe>

In most cases, the bagID and the property ID would be generated by the
RDF processor (although most RDF processors don't currently do this).
Let's use a more terse URI for this document e.g. "ECResults". Then
you would get something like the triples below. 
They start out with the ground statement. Then there is the triples
for the reified statement resource. Finally there is the triple for
the reference from the Bag representing the rdf:Description to the
reified resource. All the generated triples have the source document
as the base URI and are therefore traceable.

Ground Statement:
 [Bush, wonThe, Election]

Reified Statement Resource:
 [ECResults#id1, type, statement]
 [ECResults#id1, subject, Bush]
 [ECResults#id1, predicate, wonThe]
 [ECResults#id1, predicate, Election]
Syntactic context for Reified Statement Resource:
 [ECResults#bag1, rdf:_1, ECResults#id1]
 [ECResults#bag1, type, Bag]


Received on Sunday, 26 November 2000 22:58:23 UTC

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