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

Re: feedback sought on ISSUE-529, ISSUE-524, ISSUE5-519, ISSUE-523

From: Khalid Belhajjame <Khalid.Belhajjame@cs.man.ac.uk>
Date: Tue, 23 Oct 2012 09:37:06 +0100
Message-ID: <CAANah+GdtL6-UMQe+3tiSj+orSCEjRzDDy_nrMqCKEj6ucxkLw@mail.gmail.com>
To: Luc Moreau <l.moreau@ecs.soton.ac.uk>
Cc: "public-prov-wg@w3.org" <public-prov-wg@w3.org>
I am happy with the responses made to answer the three issues.

Thanks, khalid

On 9 October 2012 12:02, Luc Moreau <l.moreau@ecs.soton.ac.uk> wrote:
>
> Dear all,
>
> I drafted a response to ISSUE-529, ISSUE-524, ISSUE5-519, ISSUE-523.
> It can be found at
> http://www.w3.org/2011/prov/wiki/ResponsesToPublicComments#PROV-DM_issues_involving_inheritance,
> and is copied below for information.
>
> Feedback welcome!
> Cheers,
> Luc
>
> --
> 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
>
>
> PROV-DM issues involving inheritance
>
> [edit]ISSUE-529 (Empty Collection)
>
> Original email:
> http://lists.w3.org/Archives/Public/public-prov-wg/2012Sep/0119.html
> Tracker: http://www.w3.org/2011/prov/track/issues/529
> Group Response:
>
> In an open world context, absence of the relation hadMember(c,e) does not
> imply that a collection c is empty. Hence, the group introduced a class
> EmptyCollection to indicate when a collection is empty.
> Figure 11, like UML diagrams, is informative. It shows that Collection and
> EmptyCollection are linked with Entity, by means of a Generalization
> association. Therefore, a Collection and EmptyCollection are also entities
> with an id and attributes.
> Concretely, prov-dm (prov-n) sees all the sub-types (e.g.
> prov:type='prov:Collection' ) as type information is expressed by the
> prov:type attribute.
> The handling of these subtypes is consistent with other subtypes in the
> model, e.g. revision, softwareAgent, etc
> Prov-dm, as a conceptual model, leaves the implementation of these inherited
> types to concrete serializations.
>
> References:
> Implemented changes:
>
> Changed the text to indicate that PROV defines no collection specific
> attributes.
> http://dvcs.w3.org/hg/prov/diff/9fb92e012cec/model/prov-dm.html
>
> Original author's acknowledgement:
>
> [edit]ISSUE-524 (Bundle/Collection)
>
> Original email:
> http://lists.w3.org/Archives/Public/public-prov-wg/2012Sep/0114.html
> Tracker: http://www.w3.org/2011/prov/track/issues/524
> Group Response:
>
> The group has already addressed ISSUE-504, explaining that Bundles are not
> Collections.
>
> References:
>
> ISSUE-504:
> http://www.w3.org/2011/prov/wiki/ResponsesToPublicComments#ISSUE-504_.28collection.2Fbundle.29
>
> References:
> Proposed changes:
>
> Changed the text to indicate that PROV defines no collection/bundle specific
> attributes.
> http://dvcs.w3.org/hg/prov/diff/9fb92e012cec/model/prov-dm.html
>
> Original author's acknowledgement:
>
> [edit]ISSUE-519 and ISSUE-523 (Influence Inheritance)
>
> Original email:
> http://lists.w3.org/Archives/Public/public-prov-wg/2012Sep/0109.html
> Original email:
> http://lists.w3.org/Archives/Public/public-prov-wg/2012Sep/0113.html
> Tracker: http://www.w3.org/2011/prov/track/issues/519
> Tracker: http://www.w3.org/2011/prov/track/issues/523
> Group Response:
>
> First, a reminder that UML diagrams are informative.
> The prov-constraints document provides normative information about
> Influence. See Inference 15.
> For instance, the following inference is permitted, allowing to infer a
> wasInfluencedBy statement from a wasGeneratedBy statement.
>
> IF wasGeneratedBy(id; e,a,_t,attrs) THEN wasInfluencedBy(id; e, a, attrs).
>
> Whatever appears as id/attributes in wasGeneratedBy becomes also
> id/attributes in wasInfluencedBy
> Whatever appears as entity (e) in wasGeneratedBy becomes influencee in
> wasInfluencedBy
> Whatever appears as activity (a) in wasGeneratedBy becomes influencer in
> wasInfluencedBy
> Given this, prov-dm should define the minimalist characteristics for
> wasInfluencedBy in a technology agnostic way.
> Inheritance is a way of implementing Inference 15 of prov-constraints (and
> this approach was successfully followed by prov-o), but it does not have to
> be implemented that way. For instance, a rule based system could simply
> implement Inference 15 without requiring inheritance. The current prov-xml
> schema does not define WasGeneratedBy as an extension if Influence. A record
> based system may not rely on inheritance.
> As the author suggests, inheritance would imply that attributes are
> inherited by the children relation. It is not the case that wasGeneratedBy
> has influencer/influencee attributes, but instead, we want to show that they
> correspond to activity/entity in that case.
> Given this, the document should be changed as follows:
>
> The UML diagram in Figure 8 should not show a Generalization association
> between WasGeneratedBy (and others) and WasInfluencedBy.
> A table should be introduced showing which attributes in
> Generation/Usage/etc are influencer or influencee.
>
> With these changes, the issue raised by the author is no longer applicable:
> it is no longer the case that wasGeneratedBy etc can be used anywhere
> between agent/activity/entity.
> For the comment "The notion of influence is useful for the PROV model, but
> it is unclear whether this is intended to represent an extension point for
> adopters of the spec. How should it be implemented?", we have shown with
> prov-o, prov-n, and prov-xml various ways of implementing Influence.
> According to Section 6, Influence is not seen as an extensibility point of
> the model, instead, it is seen as a means to express influence in PROV
> without being specific about its nature. We note the following, quoted from
> the specification:
>
> It is recommended to adopt these more specific relations when writing
> provenance descriptions. It is anticipated that the Influence relation may
> be useful to express queries over provenance information.
>
> References:
>
> Inference 15:
> http://www.w3.org/TR/2012/WD-prov-constraints-20120911/#influence-inference
> Current xml schema:
> http://dvcs.w3.org/hg/prov/file/f0e8bc2ae457/xml/schema/prov.xsd
> Extensibility section: http://www.w3.org/TR/prov-dm/#extensibility-section
>
> Implemented changes:
>
> Changed figure 8, removing Generalization relation between
> WasGeneratedBy,etc and WasInfluencedBy
> Added table 7.
> http://dvcs.w3.org/hg/prov/diff/9fb92e012cec/model/prov-dm.html
>
> Original author's acknowledgement:
>
> [edit]
>
Received on Tuesday, 23 October 2012 08:37:33 UTC

This archive was generated by hypermail 2.3.1 : Tuesday, 6 January 2015 21:58:20 UTC