Re: multiple-graph example in the Primner

On 12/7/13 7:54 AM, Sandro Hawke wrote:
> Pat, I agree with you about the situation except I believe there's a way out, which is why I stopped objecting back when we were making these decisions.  The way out is to define some vocabulary which communicates from Alice to Bob what kind of dataset semantics Alice is using.   That vocabulary doesn't need to be defined in a W3C recommendation to work.  So the primer just needs to posit that such vocabulary might exist, and give the example as a hypothetical.  Alternatively, we could define that vocabulary (non rec track) right now and use it in the primer with a caution that this is only one of many possible ways to use datasets.
>
>       - Sandro

Yes, a vocabulary can be used to solve the problem. Net effect, we still 
don't need a confusing and contradictory example in the spec :-)

Kingsley
>
> Pat Hayes <phayes@ihmc.us> wrote:
>> On Dec 5, 2013, at 4:53 AM, Guus Schreiber <guus.schreiber@vu.nl>
>> wrote:
>>
>>> In the telecon yesterday there were some flames about the graph
>> metadata examples in the Primer.
>>> My position:
>>> - There needs to be at least one example triple in the Primer in
>> which a graph name is being used. Dropping this completely is for the
>> editors a no-go.
>>
>> Including such an example is a no-go for me. I will formally object (or
>> protest, or register a dissent, I am not sure of the exact W3C process
>> involved here) if the WG publishes any document which implies that such
>> usage is in any way supported by the RDF 1.1 specifications. That is
>> *exactly* the semantic stumbling-point at which we were unable to
>> provide any semantics for datasets. RDF 1.1 does NOT imply in any way
>> that the use of a graph-name in an RDF triple can or should be
>> understood to refer to the graph. On the contrary, it explicitly denies
>> the validity of such an assumption.
>>
>>> - We are happy to consider other examples. Please suggest.
>>> - We're happy to include other/updated caveats
>>>
>>> Current phrasing included below. Text suggestions very much
>> appreciated!
>>> Guus
>>>
>>> From
>> https://dvcs.w3.org/hg/rdf/raw-file/default/rdf-primer/index.html#subsection-multiple-graphs
>> :
>>> [[
>>> We can write down triples that include a graph name, for example:
>>>
>>>   <http://example.org/bob> <is published by> <http://example.org>.
>>>   <http://example.org/bob> <has license>
>>>       <http://creativecommons.org/licenses /by/3.0/>.
>>>
>>> These two triples could be interpreted as license and provenance
>> information of the graph http://example.org/bob.
>>> NOTE
>>> RDF does not define the way in which the graph name and the graph are
>> related. It is therefore up to application developers to decide how to
>> interpret such triples.
>>
>> That does not deal with the central difficulty. RDF is intended for use
>> in publishing data on the open Web. The issue involved here is, if
>> Alice publishes an RDF dataset, and Bob reads it, how can Bob know
>> whether a graph name used in RDF in the datset should be interpreted as
>> referring to the graph it names? And the clear, unambiguous answer
>> given by our RDF specs is, Bob cannot know this. There is no way
>> specified to record or transmit this information through RDF or any
>> means usable by an RDF engine. Alice might conform to the metadata
>> useage needed by PROV, and Bob might read this and interpret it
>> differently, without failing in any way to conform to RDF. So as far as
>> RDF is concerned, this usage is invisible. Vague references to
>> "application developers" does not deal with this issue.
>>
>> Pat
>>
>>> ]]
>>>
>>>
>>>
>>>
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>
>
>


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