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Re: RDF/XML shorthand for RDF reification

From: Alan Ruttenberg <alanruttenberg@gmail.com>
Date: Thu, 26 Jun 2008 09:41:34 -0400
Cc: "Peter F. Patel-Schneider" <pfps@research.bell-labs.com>, public-owl-wg@w3.org
Message-Id: <908F480A-0256-4986-8066-9D8F89C427AB@gmail.com>
To: Ivan Herman <ivan@w3.org>


On Jun 26, 2008, at 5:32 AM, Ivan Herman wrote:

> I was actually surprised to see that Peter was right:-) I must admit  
> that I thought myself that the rdf:nodeId could also be used in that  
> position (generating a blank node for the reified statement) but,  
> indeed,
>
> http://www.w3.org/TR/rdf-syntax-grammar/#section-Syntax-reifying
>
> refers to rdf:ID only. Having said that (and that may be the reason)  
> I do not think I have ever seen this rdf:ID+reification trick ever  
> used in practice...
>
> As both Alan and Peter said: this is independent on whether the  
> reified triple should appear in the RDF graph explicitly or not.  
> Actually (I am sorry Alan...) I do not think any RDF/XML syntax  
> trick (whether there is a remedy or not) has any relevance here.  
> Indeed, we should not rely on the particularities, oddities, etc, of  
> one particular RDF serialization

Just for the record, I wasn't suggesting relying on it as much as not  
ruling it out so it can be taken advantage of. I have seen it used,  
but I'd have to look for the examples. I've sent a note to HP asking  
how much they've seen it in Jena.

> and we should keep to the RDF model. For the record, I believe Alan  
> is right and we should have that extra triple in the graph; I saw no  
> reason why we wanted to differentiate ourselves from RDFS/OWL Full  
> semantics at that point...
>
> Ivan
>
> Alan Ruttenberg wrote:
>> On Jun 25, 2008, at 3:50 PM, Peter F. Patel-Schneider wrote:
>>> The point I was making was that using the shorthand results in the
>>> reification node having a real name, i.e., not being a blank node,  
>>> which
>>> messes up lots of things, including parsing and semantics.   
>>> Therefore,
>>> arguments that rely on using the shorthand are not applicable, at  
>>> least
>>> without doing some investigation to see whether there is a remedy.
>> OK. I see this now. Good point. I'll poke around to see if there is  
>> a remedy.
>> -Alan
>>>
>>> This has nothing to do whether one would like to have the base  
>>> triple or
>>> not.
>>>
>>> peter
>>>
>>> From: Alan Ruttenberg <alanruttenberg@gmail.com>
>>> Subject: Re: RDF/XML shorthand for RDF reification
>>> Date: Wed, 25 Jun 2008 14:40:03 -0400
>>>
>>>> The point I was making is that it that I though that it was  
>>>> unreasonable
>>>> for owl not to have the reified triple, and therefore this is well
>>>> suited ;-)
>>>>
>>>> I also pointed out that it nullified the argument that there was an
>>>> additional parsing burden to parse the "extra" actual reified  
>>>> triple. In
>>>> effect the RDF/XML shorthand makes the parsing burden for a fully
>>>> reified triple only slightly more than for the triple itself.
>>>>
>>>> -Alan
>>>>
>>>> On Jun 25, 2008, at 2:15 PM, Peter F. Patel-Schneider wrote:
>>>>
>>>>>
>>>>> It appears to me that the RDF/XML shorthand for RDF reification  
>>>>> creates
>>>>> named reification, i.e., it names the reified triple.  I believe  
>>>>> that
>>>>> this means that its use is not reasonable for OWL.
>>>>>
>>>>> peter
>
> -- 
>
> Ivan Herman, W3C Semantic Web Activity Lead
> Home: http://www.w3.org/People/Ivan/
> PGP Key: http://www.ivan-herman.net/pgpkey.html
> FOAF: http://www.ivan-herman.net/foaf.rdf
Received on Thursday, 26 June 2008 13:42:13 GMT

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