Re: a view of SPIN constraints

Hi,

@Peter: are you referring to what is commonly referred to as "non-standard use" of the RDFS vocabulary?
Cf. http://books.google.at/books?id=Ah_pAwAAQBAJ&pg=PA105 Def.5.5


@Holger: While I agree that non-standard use can lead to unintuitive behavior, I don't agree 
with the general statement, that 

>>  RDFS doesn't have intuitive semantics, esp rdfs:domain and range are a source of
>> frequent user pain.


I think that the semantics of subclassOf,subPropertyOf, domain, and range is very 
straightforward...
Can you explain in more detail what you mean by "frequent user pain" here, or was it 
only non-standard use you were referring to here?

best,
Axel

--
Prof. Dr. Axel Polleres
Institute for Information Business, WU Vienna
url: http://www.polleres.net/  twitter: @AxelPolleres

On 04 Nov 2014, at 04:37, Peter F. Patel-Schneider <pfpschneider@gmail.com> wrote:

> Well not only subproperties of rdf:type but also subproperties of rdfs:subClassOf.
> 
> peter
> 
> 
> On 11/03/2014 12:58 PM, Holger Knublauch wrote:
>> 
>> On 11/4/14, 3:06 AM, Peter F. Patel-Schneider wrote:
>>> One aspect of this definition is that SPIN does not completely abide by the
>>> RDFS definition of the instances of classes.
>> 
>> Could you clarify - do you mean sub-properties of rdf:type?
>> 
>> And in general, it is not the goal of SPIN to have full RDFS support. RDFS
>> doesn't have intuitive semantics, esp rdfs:domain and range are a source of
>> frequent user pain.
>> 
>> Thanks
>> Holger
>> 
>> 
>>> 
>>> peter
>>> 
>>> On 10/31/2014 01:04 PM, Holger Knublauch wrote:
>>>> Yeah that looks right. I think we only need to define the semantics of the
>>>> CONSTRUCT case and treat ASK as syntactic sugar with default values for the
>>>> constructed ConstraintViolations.
>>>> 
>>>> Holger
>>>> 
>>>> 
>>>> On 11/1/14, 4:05 AM, Peter F. Patel-Schneider wrote:
>>>>> Here is my reconstruction of how SPIN constraints work, based on my reading
>>>>> of various SPIN documents and various presentations about SPIN constraints.
>>>>> Please let me know if anything is wrong.
>>>>> 
>>>>> Conceptually a SPIN constraint system takes in two inputs:
>>>>> 1/ an RDF graph
>>>>> 2/ a set of SPIN constraints
>>>>> 
>>>>> Each SPIN constraint is attached to a class and provides a constraint in the
>>>>> form of a SPARQL query fragment plus an optional SPARQL construct clause.
>>>>> The surface syntax may not always look like query fragments and construct
>>>>> clauses, but the only things that determine the meaning of a SPIN
>>>>> constraint are the query fragment and construct clause that can be generated
>>>>> from the surface syntax.
>>>>> 
>>>>> A constraint with SPARQL query fragment F on class C is satisfied if the
>>>>> SPARQL query
>>>>>   ASK {
>>>>>     ?this rdf:type/rdfs:subClassOf* C .
>>>>>     F }
>>>>> returns no bindings for the graph G
>>>>> 
>>>>> If there is a construct clause X then the result of the constraint is the
>>>>> result of the SPARQL query
>>>>>   CONSTRUCT { X }
>>>>>   WHERE {
>>>>>    ?this rdf:type/rdfs:subClassOf* C .
>>>>>    F }
>>>>> evaluated against the graph G.
>>>>> 
>>>>> 
>>>>> peter
>>>>> 
>>>> 
>>>> 
>> 
>> 
>

Received on Tuesday, 4 November 2014 06:41:36 UTC