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Re: PROV-ISSUE-471 (wrong-wasAttributedTo-constraints): wasAttributedTo constraints not sensical [prov-dm-constraints]

From: Luc Moreau <l.moreau@ecs.soton.ac.uk>
Date: Mon, 03 Sep 2012 14:52:24 +0100
Message-ID: <EMEW3|b79faf0f3593d6d456f645d9fde5a002o82EqS08l.moreau|ecs.soton.ac.uk|5044B618.5020709@ecs.soton.ac.uk>
To: public-prov-wg@w3.org
Hi Stian,

Re-reading the prov-constraints document, I think I disagree with one 
of  your suggestions.



On 06/08/12 16:37, Provenance Working Group Issue Tracker wrote:
> PROV-ISSUE-471 (wrong-wasAttributedTo-constraints): wasAttributedTo constraints not sensical [prov-dm-constraints]
>
> http://www.w3.org/2011/prov/track/issues/471
>
> Raised by: Stian Soiland-Reyes
> On product: prov-dm-constraints
>
> I find the wasAttributedTo constraint 48 wrong
>
> >From Stian's review http://lists.w3.org/Archives/Public/public-prov-wg/2012Aug/0021.html
>
> http://dvcs.w3.org/hg/prov/raw-file/default/model/releases/ED-prov-constraints-20120723/prov-constraints.html#wasAttributedTo-ordering_text
>
>> An entity that was attributed to an agent must have some overlap with the agent.
> Why??
>
>
>> The agent is required to exist before the entity invalidation.
> I don't agree with that. First of all, why has the attribution need to
> have anything to do with the invalidation of an entity? If you
> contribute to an entity, all of that has to happen *before* the entity
> is generated. It does not matter what happens after that.
>

Why should this be *before* the entity exist?

I believe one can use attribution as follows:
wasAttributedTo(painting,Bob,[prov:type="ownership"])

I don't see why Bob should exist before the painting was created.

So, to me, it makes sense that attribution relates the agent to the 
invalidation of the entity.


>> Likewise, the entity generation must precede the agent destruction.
> This also means it is not valid to attribute a book to an author if
> the book was published after the author's death. (For instance The
> GIrl with the Dragon Tattoo).
>
> By our inferences, it is only a requirement that the agent was
> associated with an activity that eventually gave birth to the entity.
> The agent is not required to be there till the end of the activity,
> that sounds like an artificial constraint to me. Thus I would remove
> constraint 48.
>

OK, I think we can relax this constraint as you suggest.

Luc

> What you can instead say that an agent's association with that
> activity must precede an entity's generation, because otherwise he
> can't be associated with its generating activity. This does not
> directly follow from constraint 47 and Inference 15
> (attribution-inference), so we need a constraint to force the
> generation to be after the *association* started, the first would then
> follow. Association don't have time, unfortunately, but we can use
> same reasoning as in constraint 47:
>
> IF wasAttributedTo(_at;e,ag,_attrs) and
> wasGeneratedBy(genE;e,_a1,_t1,_attrs1) and
> wasGeneratedBy(genAg;ag,_a1,_t1,_attrs1) THEN genAg precedes genE
>
>
> We can't say anything about the entity's invalidation; attribution
> relates to association with the generation, not invalidation. The
> agent's invalidation after the start of the activity a1 (which does
> not affect e) is covered by constraint 47+ inference 15.
>   
>
>
>

-- 
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, 3 September 2012 13:53:03 GMT

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