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Re: PROV-ISSUE-447: subactivity relation [prov-dm]

From: Paul Groth <p.t.groth@vu.nl>
Date: Tue, 4 Sep 2012 17:42:57 +0100
Message-ID: <CAJCyKRpRDAhH9YNmkX1uKYkNV5_yEQTDBh6H_MRSJ0Mf=f8Tcw@mail.gmail.com>
To: Luc Moreau <l.moreau@ecs.soton.ac.uk>
Cc: Khalid Belhajjame <Khalid.Belhajjame@cs.man.ac.uk>, "public-prov-wg@w3.org" <public-prov-wg@w3.org>
Hi,

There seems to be some beginning of a consensus that the furtherest we
would go would be to define a "place-holder" relationship that does
not require us to revisit constraints. The question then is to whether
such a place-holder relationship would be in the prov namespace or
exist outside of it such as dc:partof.

We do have some backing for defining such a place holder relationship
in prov namely prov:hasMember. On the other hand, it may be odd to
have such a relation without having more specifics given the work that
went into prov:specializationOf.

cheers
Paul

On Tue, Sep 4, 2012 at 5:31 PM, Luc Moreau <l.moreau@ecs.soton.ac.uk> wrote:
> Hi Khalid,
>
> I am opposed to introduce wasSubactivityOf without studying
> constraints/inferences/etc...
>
> I don't think this example makes much sense:
>
> activity(a1,2011-11-16T00:00:00,2011-11-17T00:00:00) // in 2011
> activity(a2,2012-11-16T00:00:00,2012-11-17T00:00:00)  // in 2012
> wasSubactivity(a1,a2)
>
> As indicated previously, it's a whole complete new design that
> we have to undertake, for which we don't have enough experience.
>
> Cheers,
> Luc
>
>
> On 04/09/12 17:23, Khalid Belhajjame wrote:
>> I would go for option 1 provided that we dont say anything from the
>> point of view of ordering sub activities, with  respect to the parent
>> activity. If the only requirement is to have a means to know that one
>> activity is a child activity of another then I dont see a problem in
>> introducing the relation sub-activity. We did some thing similar with
>> collections to a certain degree, when we choose to keep in the DM the
>> membership relation, so why not do the same for activities.
>>
>> Thanks, khalid
>>
>> On 4 September 2012 14:57, Luc Moreau <l.moreau@ecs.soton.ac.uk> wrote:
>>>
>>> Dear all,
>>>
>>> I would like to kickstart discussion on this public comment.
>>> This has already been asked on several occasions, and this has previously
>>> been raised on the mailing list.
>>>
>>> I essentially see two options:
>>> 1. We change the model and add a sub-activity relation.
>>> 2. We don't change the model, but we come with a good justification for not
>>>      changing it.  In particular, we previously said this was out of scope.
>>> Perhaps,
>>>      we could point to some vocabularies already doing this.
>>>
>>> What are your views?
>>> Regards,
>>> Luc
>>>
>>>
>>> On 06/07/12 18:12, Provenance Working Group Issue Tracker wrote:
>>>> PROV-ISSUE-447: subactivity relation [prov-dm]
>>>>
>>>> http://www.w3.org/2011/prov/track/issues/447
>>>>
>>>> Raised by: Timothy Lebo
>>>> On product: prov-dm
>>>>
>>>> There is a thread discussing the issue raised by Sutra at
>>>> http://www.w3.org/mid/CAJCyKRqtC47OWc_rDRhFcQGdJ-yy2toQBCguUywFGZpHO5Q8Jw@mail.gmail.com
>>>>
>>>> The original email:
>>>>
>>>> On Fri, Jul 6, 2012 at 2:45 PM, Satrajit Ghosh <satra@mit.edu> wrote:
>>>> hello,
>>>>
>>>> i was discussing this with luc and based on his feedback thought it might
>>>> be
>>>> useful to bring this up on the list.
>>>>
>>>> ----
>>>> question:
>>>> how do you encode that a certain activity "emailing a letter" happened
>>>> during another activity "a meeting"?
>>>>
>>>> for example we conduct research studies/projects.
>>>>
>>>> activity(p1, [prov:type='ex:Project'])
>>>> activity(p2, [prov:type='ex:MRIScanning', ex:session=1])
>>>> activity(p3, [prov:type='ex:MRIScanning', ex:session=2])
>>>>
>>>> how would i encode that this activity p2 and p3 were conducted during p1?
>>>> how would i encode p3 followed p2?
>>>>
>>>>
>>>> luc's response:
>>>> Regarding your question, there may be a few options:
>>>> you could add time information to your activities. This will help you
>>>> understand their ordering.
>>>>
>>>> Alternatively, if you want an explicit dependency in your graph, then p2
>>>> may
>>>> generate something
>>>> that starts p3, and/or is consumed by p3
>>>>
>>>> Finally, prov doesn't have relations between activities, to express their
>>>> nesting, etc. It's important
>>>> but we felt this is not specific to provenance, but to process executions.
>>>> ----
>>>>
>>>> it's the last point on this response that i was not completely sure about.
>>>> why "relations between activities" is "not specific to provenance, but to
>>>> process executions."
>>>>
>>>> in the above example, one could say:
>>>>
>>>> wasSubtaskOf(p2, p1)
>>>> wasSubtaskOf(p3, p1)
>>>> wasFollowedBy(p2, p3)
>>>>
>>>> any clarification as to why such relations would be outside the realm of
>>>> provenance would be much appreciated.
>>>>
>>>> cheers,
>>>>
>>>> satra
>>>>
>>>>
>>>>
>>> --
>>> 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
>>>
>>>
>
> --
> 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
>
>



-- 
--
Dr. Paul Groth (p.t.groth@vu.nl)
http://www.few.vu.nl/~pgroth/
Assistant Professor
- Knowledge Representation & Reasoning Group |
  Artificial Intelligence Section | Department of Computer Science
- The Network Institute
VU University Amsterdam
Received on Tuesday, 4 September 2012 16:43:30 GMT

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