Re: transparency and entailment

Aah, yes, I see how a modal semantics would violate your criterion.

But what about rolling up the CG semantics, something along the lines of

I(a b <<s p o>>) = true  iff
   < I(a), IQ(<<s p o>>) > in EXT(I(b))
   and < IQ(<<s p o>>), I("s"^^xsd:string) > in EXT(rdf:subject) if s is an IRI
   and ...

This seems to match your criterion but is not transparent.

Admittedly it is a strange semantics, but you haven't ruled out strange semantics.

peter



On 2/19/24 07:57, Franconi Enrico wrote:
> I don’t know why named graphs should play a role in my characterisation.
> Given a /_model_/ of a RDF graph, if an IRI or a bnode or a literal is 
> interpreted in the same way regardless of where it does appear in the graph, 
> then that IRI or bnode or literal has a transparent interpretation.
> I stick with that.
> —e.
> 
>> On 19 Feb 2024, at 13:48, Peter F. Patel-Schneider <pfpschneider@gmail.com> 
>> wrote:
>>
>> It appears to me that a modal semantics using named graphs would fit your 
>> characterization but not be transparent.
>>
>> peter
>>
>> On 2/19/24 06:52, Franconi Enrico wrote:
>>>> On 17 Feb 2024, at 20:18, Peter F. Patel-Schneider 
>>>> <pfpschneider@gmail.com> wrote:
>>>>
>>>> I think that this characterization is not sufficient for transparency. 
>>>> Consider the CG semantics, which is a macro-expansion that then uses the 
>>>> usual RDF semantics, which does satisfy your criterion.  But the CG 
>>>> version of quoted triples is not transparent.
>>> My characterisation is sufficient whenever RDF has a direct model-theoretic 
>>> semantics, which the CG semantics is not (it is based on a translation).
>>> RDF-star will have a direct model theoretic semantics, if I am going to 
>>> remain in the WG :-)
>>> —e.
>>>>
>>>> peter
>>>>
>>>> PS:  I suspect that you would want to include literals as well.
>>>>
>>>> On 2/17/24 10:12, Franconi Enrico wrote:
>>>>> To me, transparency means:
>>>>> given a graph G, II is the set of all IRIs appearing in G and BB is the 
>>>>> set of all bnode symbols appearing in G.
>>>>> Then, ∀ i∈II and b∈BB, i and b have the same denotation non matter where 
>>>>> they appear within the graph.
>>>>> I guess that your definition below is somehow different, but probably it 
>>>>> boils down to mine, which is more clear, I guess.
>>>>> —e.
>>>>>> On 16 Feb 2024, at 18:04, Pierre-Antoine Champin <pierre-antoine@w3.org> 
>>>>>> wrote:
>>>>>>
>>>>>> Peter,
>>>>>>
>>>>>> On 09/02/2024 20:24, Peter F. Patel-Schneider wrote:
>>>>>>> There was some discussion of transparency in the semantics call today, 
>>>>>>> with disagreement over just what transparency means.
>>>>>>>
>>>>>>> My view is that transparency (for well-formed graphs) means that 
>>>>>>> entailments are exactly the same if a subject, predicate, or object in 
>>>>>>> a quoted triple is replaced by a semantically identical identifier.  So 
>>>>>>> if an option for << e | s p o >> is transparent in D-entailment then
>>>>>>>
>>>>>>> << :e | :s :p "4"^^xsd:integer >> :a :b .
>>>>>>>
>>>>>>> entails
>>>>>>>
>>>>>>> << :e | :s :p "04"^^xsd:integer >> :a :b .
>>>>>>>
>>>>>>> in that option.
>>>>>>
>>>>>> that's also my interpretation of "transparency".
>>>>>>
>>>>>> (and I assume that the entailment in your example above works both ways)
>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> peter
>>>>>>>
>>>>>> <OpenPGP_0x9D1EDAEEEF98D438.asc>
>

Received on Monday, 19 February 2024 13:13:33 UTC