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Re: Why do we name nodes and not edges?

From: Melvin Carvalho <melvincarvalho@gmail.com>
Date: Mon, 30 Jul 2012 13:53:43 +0200
Message-ID: <CAKaEYhLhAxXZMpohd_xqOB1f+ygbM2iG88N6PyFaBnm_-9VmUw@mail.gmail.com>
To: Natasa Bulatovic <bulatovic@mpdl.mpg.de>
Cc: semantic-web@w3.org
On 25 July 2012 18:11, Natasa Bulatovic <bulatovic@mpdl.mpg.de> wrote:

> Could you point to some examples where this scenario would be useful or
> recommended?
>

I dont really have a specific use case in mind, it's more a kind of high
level question.

If naming is the most important thing we do, and we go to a lot of effort
naming nodes, why is it that we seemingly put less effort in naming edges.

Of course it's possible to construct use cases.

<#alice> :isInARealtionshipWith <#bob>

I may want to +1 this triple for example.

It also becomes easier to point to data, sign it etc.

But really my question is regarding the naming in general.

Follow up question:  could we quickly come to a consensus for a best
practice to do this e.g.

urn : uuid/eav : subject delimiter predicate delimiter object


>
> 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<http://example.com/edge/123456>>
>>>> 1 .
>>>> <http://example.com/edge/**123456 <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
> fax: +49-89-38602-280
>
>
>
>
Received on Monday, 30 July 2012 11:54:16 UTC

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