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Re: PROV-ISSUE-222 (used-objectproperty): Datatype property for used? [Ontology]

From: Timothy Lebo <lebot@rpi.edu>
Date: Mon, 16 Apr 2012 13:45:29 -0400
Cc: Stian Soiland-Reyes <soiland-reyes@cs.manchester.ac.uk>, public-prov-wg@w3.org, Luc Moreau <l.moreau@ecs.soton.ac.uk>
Message-Id: <0B703059-E894-4A39-820D-6BD99473A49B@rpi.edu>
To: Stephan Zednik <zednis@rpi.edu>

On Apr 16, 2012, at 1:31 PM, Stephan Zednik wrote:

> 
> On Apr 16, 2012, at 11:15 AM, Timothy Lebo wrote:
> 
>> 
>> On Apr 16, 2012, at 11:44 AM, Stian Soiland-Reyes wrote:
>> 
>>> prov:value can specialize rdf:value ( and standards say so), but for is it would not really add any meaning beyond anything given by its domain (say prov:Entity).
>>> 
>> 
>> I don't see the need to mirror it when rdf:value works just fine and already recognized by so many tools.
> 
> While rdf:value is recognized by tools, it has no defined meaning on its own (according to http://www.w3.org/TR/rdf-schema/#ch_value).

Thanks for pointing this out.
"rdf:value is an instance of rdf:Property that may be used in describing structured values."
is NOT how rdf:value has come to be used in the wild.

Funny that the example that they cite doesn't use rdf:value …. http://www.w3.org/TR/2004/REC-rdf-primer-20040210/#example16

So then I'd propose we make prov:value a DatatypeProperty and provide a better definition than what the RDF spec provided.


>  I also believe direct usage without restricting its type to owl:ObjectProperty or owl:DatatypeProperty also puts an ontology into OWL Full.

Another huge reason to define our own :-)

> 
>> 
>>> But we want string activities as well?
>>> 
>>> 
>> 
>> That's impossible. (and one says that, it means they should make an axiom…. prov:value rdfs:domain prov:Entity (which is disjoint with Activity))
>> But worth it's weight of another property?
> 
> It seems to me we are conflating simple descriptions of activities and entities with the actual activity and entity resource.

I agree that this conflation is bad, but I can't say that I'm seeing it.
Perhaps it's because there isn't an example on this issue yet.

> 
> Why not just have an annotation that provides a human-readable description of the activity or entity?
> 
> To replace Activity/Entity individuals with string descriptions of said individuals would be a mistake.

+100

-Tim


> 
> --Stephan
> 
>> 
>> 
>>> We should be careful not to overlap rdfs:label...
>>> 
>>> 
>> 
>> Who proposed using rdfs:label?
>> Agreed, this should be left out of the discussion.
>> 
>> -Tim
>> 
>> 
>> 
>> 
>>> On Apr 16, 2012 4:36 PM, "Timothy Lebo" <lebot@rpi.edu> wrote:
>>> 
>>> On Apr 16, 2012, at 10:49 AM, Luc Moreau wrote:
>>> 
>>> > Hi Tim,
>>> >
>>> > Just a word to say that it's a problem that is not specific to the ontology.
>>> > The problem is similar in other serializations.
>>> > Should we have a statement about this in the dm?
>>> 
>>> That makes sense. Would you life to reserve prov:value?
>>> PROV-O will not define prov:value in favor of rdf:value.
>>> I think the rest of the PROV-O solution (content in RDF vocab) would fall outside of DM's control, as we've done before.
>>> 
>>> -Tim
>>> 
>>> > Luc
>>> >
>>> > On 04/16/2012 02:18 PM, Timothy Lebo wrote:
>>> >> Paul (and Graham),
>>> >>
>>> >> The prov-o team discussed this last week and agreed that this topic is more appropriate in the best practices document.
>>> >> We also outlined the recommended patterns.
>>> >>
>>> >> I put a stub entry at
>>> >>
>>> >> http://dvcs.w3.org/hg/prov/raw-file/1a7d883e143e/bestpractices/BestPractices.html#using-strings
>>> >>
>>> >> that says:
>>> >>
>>> >> * If you want to break RL and any tools built around PROV-O, just use a string.
>>> >> * If you want to follow the datatype/objectproperty distinction, use a resource with rdf:value OR
>>> >> * use content in rdf http://www.w3.org/TR/Content-in-RDF10/
>>> >>
>>> >> 1)
>>> >> Can we move this issue to the best practices product?
>>> >> http://www.w3.org/2011/prov/track/products/7
>>> >>
>>> >> 2)
>>> >> Can you put a "string-heavy" example into http://www.w3.org/2011/prov/wiki/PROV_examples to motivate further development of the best practice?
>>> >>
>>> >> 3)
>>> >> Can we close ISSUE-248 http://www.w3.org/2011/prov/track/issues/248 as a duplicate of this issue?
>>> >>
>>> >>
>>> >> On Jan 19, 2012, at 4:36 AM, Graham Klyne wrote:
>>> >>
>>> >>
>>> >>> Paul,
>>> >>>
>>> >>> This problem is, IMO, an atifact of the arguably arbitrary restrictions of description logic and OWL-DL.  If you don't need to be consrainted to OWL-DL then the problem does not arise.  Just saying.
>>> >>>
>>> >> The problem does arise practically, too. If the range of prov:used is a rdfs:Resource, then tools will handle it as such (and not a string).
>>> >> So tools will choke while reading your account, even if they don't care about reasoning.
>>> >>
>>> >>
>>> >>
>>> >>> Staying with the object/datatype property distinction, I think either of your suggested approaches can work, but I don't know about semantics of entity here - it seems to me that it should be possoible to formulate the semantics around two properties as well as one, even if the formulation is more complex.
>>> >>>
>>> >>
>>> >>
>>> >>> The second approach avoids the semantic uncertainties at the costof some added complexity in RDF representation.
>>> >>>
>>> >>
>>> >> @Graham, could you elaborate this approach, so that we can articulate it in the best practices document?
>>> >>
>>> >> Thanks,
>>> >> Tim
>>> >>
>>> >>
>>> >>
>>> >>
>>> >>> I'm not sure this helps :(
>>> >>>
>>> >>> #g
>>> >>> --
>>> >>>
>>> >>> On 18/01/2012 09:40, Provenance Working Group Issue Tracker wrote:
>>> >>>
>>> >>>> PROV-ISSUE-222 (used-objectproperty): Datatype property for used? [Ontology]
>>> >>>>
>>> >>>> http://www.w3.org/2011/prov/track/issues/222
>>> >>>>
>>> >>>> Raised by: Paul Groth
>>> >>>> On product: Ontology
>>> >>>>
>>> >>>> Currently, prov-o:used is defined as an objectproperty. This is fine. However, we've be doing some modeling here at the VU where the parameter to a program is a string. Currently, this is not modelled using a prov-o:used edge but it seems like it should be. Is there anyway we can support this?
>>> >>>>
>>> >>>> My first inclination is to define a corresponding datatype property but this make break the semantics of entity...
>>> >>>>
>>> >>>> Another option might be to suggest using a blank node with the string attached using an application specific predicate.
>>> >>>>
>>> >>>> Suggestions?
>>> >>>>
>>> >>>>
>>> >>>>
>>> >>>>
>>> >>>>
>>> >>>
>>> >>>
>>> >>
>>> >>
>>> >
>>> > --
>>> > Professor Luc Moreau
>>> > Electronics and Computer Science   tel:   +44 23 8059 4487
>>> > University of Southampton          fax:   +44 23 8059 2865
>>> > Southampton SO17 1BJ               email: l.moreau@ecs.soton.ac.uk
>>> > United Kingdom                     http://www.ecs.soton.ac.uk/~lavm
>>> >
>>> >
>>> >
>>> 
>>> 
>> 
> 
Received on Monday, 16 April 2012 17:46:50 GMT

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