Re: shapes as classes

On 12/28/2014 02:16 PM, Eric Prud'hommeaux wrote:
> * Johnston, Patrick - Hoboken <pjohnston@wiley.com> [2014-12-28 14:26-0500]
[...]
>> The soapbox bit
>> ===============
>>
>> I am not sufficiently well-versed in the theory to understand why a shape
>> cannot always be a class in the pure RDF schema sense. I just want a Thing
>
> One issue is that some data doesn't have type arcs and pretty much no
> data has type arcs that fully enumarate all of the shapes that it
> might fit. For example, your system might use foaf:Person in a couple
> ways with different constraints on what properties must or may
> appear. You can attach one schema to foaf:Person for one use but as
> soon as you have two, you have mutually inconsistency and effectively
> a truth maintenance system.

OWL and OWL constraints (Stardog ICV) and even RDFS do not need any type arcs 
in the input graph.  It is perfectly reasonable to use RDFS domains and ranges 
to infer type information.  It is also perfectly reasonable to use OWL defined 
classes to infer type information.  This inferred type information can then be 
used in OWL constraints.

SPIN can also work perfectly well without any type arcs in the input graph, 
even without doing any RDFS or OWL inferencing.


It is also not the case that there is necessarily a 1-1 map between ontologies 
and sets of OWL constraints or SPIN constraints.  Both OWL constraints and 
SPIN can be run with a separate argument providing the consraints, as in 
"verify that the constraints in C are validated in the RDF graph G under the 
ontology O".  This lets the same graph and ontology be run with different 
constraint sets.

peter

[...]

Received on Monday, 29 December 2014 16:24:24 UTC