Re: JSON-LD Telecon Minutes for 2011-07-04

On 7/5/11 6:23 PM, Bradley Allen wrote:
> Allow me to jump into the breach here with a reworded set of points
> that attempt to capture Kingsley's feedback:
>
> 1. Linked Data is a set of documents, each containing a representation
> of a linked data graph.
> 2. A linked data graph is a labeled directed graph, where nodes are
> subjects or objects, and edges are properties.
> 3. A subject is any node in a linked data graph with at least one outgoing edge.
> 4. A subject MAY be labeled with an IRI.
> 5. A property is an edge of the linked data graph.
> 6. A property SHOULD be labeled with an IRI.
> 7. An object is a node in a linked data graph with at least one incoming edge.
> 8. An object MAY be labeled with an IRI.
> 9. An IRI that is a label in a linked data graph SHOULD be
> dereferencable to a Linked Data document describing the labeled
> subject, object or property.

Yep!!

de-referencable IRIs are mandatory re. Linked Data.

Kingsley
> Bradley P. Allen
> http://bradleypallen.org
>
>
>
> On Tue, Jul 5, 2011 at 10:12 AM, Gregg Kellogg<gregg@kellogg-assoc.com>  wrote:
>> Kingsley, thanks for the feedback.
>>
>> If you're requiring as a basic precept that every URI used in an LD graph be de-referencable, this would leave out statements of the set of URIs that are not de-referencable. This would seem to also include URNs. I don't think it's appropriate to limit JSON-LD to use only de-referencable URIs. However, I do believe that a best practice (where feasible) is to use de-referencable URIs, where a suitable representation is returned.
>>
>> Otherwise, can you suggest a re-wording of the LD points in [1] that would be more accurate?
>>
>> Gregg
>>
>> [1] http://json-ld.org/requirements/latest/#linked-data
>>
>> On Jul 5, 2011, at 1:45 AM, Kingsley Idehen wrote:
>>
>>> On 7/5/11 7:09 AM, Manu Sporny wrote:
>>>> Topic: Formal Definition of Linked Data
>>> First assertion about Linked Data reads:
>>> Linked Data is used to represent a directed graph .
>>>
>>> Sorry, but that's back to front, at best.
>>>
>>> A directed graph used to represent (describe) an object can be
>>> constructed in such a way that subject name, subject attributes, and
>>> subject attribute values take the form of de-referencable URIs.
>>>
>>> In the case of Linked Data, specifically, a URI de-references to a
>>> representation of its Referent. It does this because an Object has
>>> Identity distinct from its Representation. Thus, an Object has a Name
>>> that's distinct from the EAV/SPO graph pictorial that delivers its
>>> description (representation). Naturually, on the Web (as is the case
>>> with a computer's local OS), said representation exists as the content
>>> of a Resource at a location (Address).
>>>
>>> Of course, you don't have to accept my definition of Linked Data. But
>>> note this, bar different turn of phrase, I've just outlined the very
>>> essence of TimBL's original Linked Data meme prior to the regressive
>>> tweak that added "(RDF* and SPARQL)" to its later revision. The day
>>> "(RDF* and SPARQL)" are dropped from the meme or described as
>>> implementation details is the day that meme returns to its GOLDEN status
>>> IMO.
>>>
>>> At this juncture, the JSON-LD definition of Linked Data is inaccurate.
>>>
>>> You can make graphs that aren't Linked Data purveyors. Thus, don't
>>> conflate graphs and linked data, let alone application of the linked
>>> data concept to a global data space such as the WWW. The specific use of
>>> URIs as part of graph construction is integral to what linked data is
>>> about.
>>>
>>>  From RDF to JSON-LD conflation remains a problem. Conflation ultimately
>>> breeds confusion.
>>>
>>> The pieces of the puzzle:
>>>
>>> 1. Graphs -- an effective data structure fine grained data representation
>>> 2. de-referencable URIs -- critical data structure tapestry (remember a
>>> URI isn't implicitly de-referencable, the URL subClassOf URI is)
>>> 3. Resources -- data (collections of eav/spo triples) containers
>>> accessible from addresses.
>>>
>>> Current list of conflation examples:
>>>
>>> 1. Resources -- everything is a resource meme is inaccurate since it
>>> dangerous ignores perception media (WWW and Real World are related but
>>> distinct media)
>>> 2. Graphs -- RDF is the only mechanism for graph representation or that
>>> graph means RDF rather than RDF being an option for graph based data
>>> representation
>>> 3. Linked Data -- to the RDFer Linked Data and RDF are one and the same
>>> 4. JSON-LD -- Linked Data is either a subset of RDF or its used to
>>> represent directed graphs.
>>>
>>> Sincerely hoping these comments are digested. I have but a single goal:
>>> kill off conflation so we can make progress re. InterWeb scale Linked
>>> Data without forcing syntax or data serialization formats on anyone.
>>> Openness isn't as easy as folks assume. To be truly open you have to
>>> invest heavily in the significant costs associated with choice.
>>>
>>>
>>> --
>>>
>>> Regards,
>>>
>>> Kingsley Idehen
>>> President&    CEO
>>> OpenLink Software
>>> Web: http://www.openlinksw.com
>>> Weblog: http://www.openlinksw.com/blog/~kidehen
>>> Twitter/Identi.ca: kidehen
>>>
>>>
>>>
>>>
>>>
>>>
>>
>>
>


-- 

Regards,

Kingsley Idehen	
President&  CEO
OpenLink Software
Web: http://www.openlinksw.com
Weblog: http://www.openlinksw.com/blog/~kidehen
Twitter/Identi.ca: kidehen

Received on Tuesday, 5 July 2011 18:08:13 UTC