W3C home > Mailing lists > Public > public-prov-wg@w3.org > November 2012

Re: Draft comments for the Organization Ontology LC (Deadline Midnight GMT November 24)

From: Jun Zhao <jun.zhao@zoo.ox.ac.uk>
Date: Sun, 25 Nov 2012 09:44:24 +0000
Message-ID: <50B1E878.7030703@zoo.ox.ac.uk>
To: pgroth@gmail.com
CC: Provenance Working Group WG <public-prov-wg@w3.org>
Thanks Paul, and Luc for his offline support.

The comments are now sent back to public-gld-comments@w3.org.

Many thanks!

-- Jun

On 11/23/12 11:44 AM, Paul Groth wrote:
> I'm fine with this.
> Paul
> On Fri, Nov 23, 2012 at 10:22 AM, Jun Zhao <jun.zhao@zoo.ox.ac.uk> wrote:
>> Dear all,
>> Please find below the draft response that Luc and I prepared for the
>> last call for comments by the eGov WG regards to the Organization
>> Ontology (http://www.w3.org/News/2012.html#entry-9606).
>> It will become the group response unless we hear objections by Saturday
>> Midnight GMT, November 24th.
>> Many thanks!
>> -- Jun
>> ====================================================================================
>> Dear Organization Ontology Editors,
>> The PROV WG reviewed the part of the document about extension to PROV.
>> Generally speaking we agree with your following extensions:
>>    - org:originalOrganization as a subproperty of prov:used,
>>    - org:resultedFrom as a subproperty of prov:wasGeneratedBy
>>    - org:ChangeEvent as a subclass of prov:Activity
>> In addition, we would like to draw your attention to the concept of
>> derivation [1] in PROV, which refers to a transformation of an entity
>> into another, an update of an entity resulting in a new one, or the
>> construction of a new entity based on a pre-existing entity. Based on
>> some general knowledge, one might expect that a new organization should
>> be a derivation of the old one, by some sort of transformation or update
>> or simply setting up a new entity. But does this indeed make sense with
>> the use cases that you consider?
>> This is a strong albeit useful assertion, enabling you to trace the
>> history of an organization. However, the semantics of the PROV model
>> does not let you infer this relationship by the combination of
>> generation and usage, i.e.,  from the following triples:
>> ex:o2  org:resultedFrom          ex:a1
>> ex:a1  org:originalOrganization  ex:o1
>> The PROV model regards ex:o1 and ex:o2 as totally unrelated, unless
>> their relationship is explicitly stated otherwise. If the definition of
>> derivation does fit your use case,  making use of this relationship in
>> your ontology will make it much more in line with the upcoming
>> provenance recommendation. So it is a matter to have a think about what
>> you intend to achieve by using the prov:used and prov:wasGeneratedBy
>> properties. If you want to include derivation in your ontology, then we
>> make the following to suggestions:
>> 1. We RECOMMEND that ex:o2 prov:wasDerivedFrom ex:o1 be explicitly
>> asserted. (or a subproperty in the org: namespace)
>> 2. Alternatively, you could add a property chain
>>         org:resultedFrom followed by org:originalOrganization =>
>> prov:WasDerivedFrom
>> The second point is that the PROV model comes with a set of implicit
>> semantics constraints (in its constraint document [2]). Although these
>> constraints are not reflected in the PROV-O, we expect that a provenance
>> validator, compliant with  this document, will validate provenance
>> statements on the Web. Therefore, it might be worthwhile to take a pause
>> and think whether the intention behind your ontology might lead to any
>> violation to relevant constraints.
>> For example, the generation-precedes-usage constraint [3] requires that
>> the event when a new organization was generated must precede the event
>> when the same organization was used in the process of generating another
>> organization.
>> Finally, we would also like to bring your attention to the concept of
>> invalidation. In the PROV data model we say that an entity can have a
>> lifetime. And the invalidation is the start of the destruction,
>> cessation, or expiry of an existing entity by an activity [4].
>> If this concept is adopted in the Organization Ontology, then you will
>> be able to specify more precisely that the cease-to-exist of the old
>> organization when a new organization was built up. Might this be helpful
>> to your use cases?
>> Please be aware that by using this concept, there are several related
>> constraints to bear in mind. An example is the
>> usage-precedes-invalidation constraint [5], which means that the event
>> when an old organization ceased to exist must follow the event when it
>> was used in the org:ChangeEvent activity.
>> We, the WG as a whole, will be happy to help you with any other issue
>> related to PROV.
>> Hope this helps.
>> Jun, on behalf of the PROV WG
>> [1] http://www.w3.org/TR/prov-dm/#term-Derivation
>> [2] http://www.w3.org/TR/2012/WD-prov-constraints-20120911/
>> [3]
>> http://www.w3.org/TR/2012/WD-prov-constraints-20120911/#generation-precedes-usage
>> [4] http://www.w3.org/TR/prov-dm/#term-Invalidation
>> [5]
>> http://www.w3.org/TR/2012/WD-prov-constraints-20120911/#usage-precedes-invalidation
Received on Sunday, 25 November 2012 09:44:47 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Sunday, 25 November 2012 09:44:47 GMT