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Re: Why do we name nodes and not edges?

From: Natasa Bulatovic <bulatovic@mpdl.mpg.de>
Date: Wed, 25 Jul 2012 18:11:44 +0200
Message-ID: <50101AC0.1000505@mpdl.mpg.de>
To: <semantic-web@w3.org>
Could you point to some examples where this scenario would be useful or 
recommended?

Cheers,
Natasa

Am 25.07.2012 18:04, schrieb Dave Reynolds:
> If I understand Steve's point he was meaning that you can mint a new 
> unique edge:xxxxxx identifier for each edge.
>
> [Presumably you could make that a subPropertyOf the actual property 
> you wanted to assert.]
>
> Cheers,
> Dave
>
> On 25/07/12 16:47, Aidan Hogan wrote:
>> Steve,
>>
>> If I understand Melvin's point, in RDF, edge:123456 is the URI of a
>> property used to label the edge, not the edge itself.
>>
>> Analogously, you don't identify a class-instance by it's class URI.
>>
>> An edge is between two things. It might be directed and it might be
>> labelled. In RDF it's both.
>>
>> Hence, the edge would encapsulate the full triple, including source
>> (subject) and target (object) nodes, as well as the label (predicate).
>>
>> Cheers,
>> Aidan
>>
>> On 25/07/2012 16:18, Steve Harris wrote:
>>> Nothing stops you from giving edges a unique URI, infact I think I've
>>> worked on systems that did that.
>>>
>>> e.g.
>>>
>>> <foo> <http://example.com/edge/123456> 1 .
>>> <http://example.com/edge/123456> a rdf:Property .
>>> ...
>>>
>>> - Steve
>>>
>>> On 2012-07-25, at 16:07, Melvin Carvalho wrote:
>>>
>>>> Sorry if this topic has been covered before, but I have a question
>>>> based on the axioms of the web, in particular:
>>>>
>>>> *Axiom 0a: Universality 2    Any resource of significance should be
>>>> given a URI.
>>>> *
>>>> In this case we consider the web to be a directed graph (of nodes and
>>>> edges), where a *node* corresponds to a *resource* but edge does not.
>>>>
>>>> We are encouraged to make nodes universal by giving them a URI.
>>>>
>>>> Why dont edges get the same treatment, ie encouragment to give it a
>>>> (universal) name.  Is it even practical?
>>>>
>>>> I know there's such thing as reification but that seems to be
>>>> unpopular (maybe before my time).
>>>>
>>>> I'm just curious as to whether this seems asymmetrical, that nodes are
>>>> seemigly treated in one way, and edges in another?
>>>
>>> -- 
>>> Steve Harris, CTO
>>> Garlik, a part of Experian
>>> +44 7854 417 874 http://www.garlik.com/
>>> Registered in England and Wales 653331 VAT # 887 1335 93
>>> Registered office: Landmark House, Experian Way, Nottingham, Notts,
>>> NG80 1ZZ
>>>
>>
>>
>
>

-- 
--
Natasa Bulatovic
Max Planck Digital Library (MPDL)
Amalienstrasse 33
80799 Munich, Germany
http://www.mpdl.mpg.de

e-Mail: bulatovic@mpdl.mpg.de
phone: +49-89-38602-223
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Received on Saturday, 28 July 2012 18:21:33 UTC

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