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

From: Stian Soiland-Reyes <soiland-reyes@cs.manchester.ac.uk>
Date: Mon, 3 Sep 2012 16:33:13 +0100
Message-ID: <CAPRnXtm5GGZ96TcPA3eeppx5Db3cnvXvwF=AF3XuLVCJs7qFnw@mail.gmail.com>
To: Luc Moreau <l.moreau@ecs.soton.ac.uk>
Cc: public-prov-wg@w3.org
On Mon, Sep 3, 2012 at 2:52 PM, Luc Moreau <l.moreau@ecs.soton.ac.uk> wrote:
>> 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 disagree.

The DM spec (my highlights):

Attribution ◊ <http://www.w3.org/TR/prov-dm/#concept-attribution> is the
ascribing of an entity to an agent.

When an entity e is attributed to agent ag, entity e was generated by some
unspecified activity that in turn was associated to agent ag. Thus, this
relation is useful when the activity is not known, or irrelevant.

An attribution ◊ <http://www.w3.org/TR/prov-dm/#dfn-wasattributedto>
 relation, written wasAttributedTo(id; e, ag, attrs) in PROV-N, has:

   - id: an *optional* identifier for the relation;
   - entity: an entity identifier (e);
   - agent: the identifier (ag) of the agent whom the entity is ascribed to,
   and therefore bears some responsibility for its existence;
   - attributes: an *optional* set (attrs) of attribute-value pairs
   representing additional information about this attribution.

Although attribute
(v)<http://www.oed.com/view/Entry/12933?rskey=xWNM2z&result=3&isAdvanced=false#eid>in
the wider sense does cover ownership:
*a.* To assign, bestow, give, concede, yield *to* any one, as his right
(property, title, authority, worship, honour).*arch.* or *Obs.
(..)
* *3.* To ascribe *to* as belonging or proper; to consider or view as
belonging or appropriate *to*.
the DM highlights "ascribe", as in:
 *6.* To ascribe, impute, or refer, as an effect *to* the cause; to reckon
as a consequence of.
 *7.* To ascribe *to* an author as his work.

This narrower understanding of 'ascribe' and 'attribute' was what I had
understood we are using, as we have not talked about ownership as a kind of
attribution before. We have been talking about a kind of "why" or "who"
made something appear - a book was written by an author, a car was
manufactured by a factory, a law was passed by its parliament. There are
many other definitions on "ascribe" and "attribute" that I likewise don't
think cover our intention with wasAttributedTo, like: *ascribe great
importance to or To ascribe as a quality or ‘attribute’ belonging.*

If I own an old and dangerous car, I am not responsible for why it *exists*,
the car manufacturer is. I might bear responsibility for why it has not yet
been *invalidated* as it is not road worthy, but that has to do with
potential future actions, intentions and plans, and I don't see how *
wasAttibutedTo* in PROV would be suitable for that.

We have said that PROV is provenance about the past. Describing that kind
of ownership would to me simply be an attribute on the entity, just like
it's location, colour, road worthiness status, insurance status, who has
access to the car keys, etc. Ownership would not in my mind imply an
activity (the "owning" activity? "purchasing"?), just like having the
colour red does not imply a "being red" activity. This is about entity vs
activity, state vs. change.

If you want to broaden the definition of *wasAttributedTo* to cover mere
'ownership' kind of attribution, I think we need to add clear examples that
show the value of this and guides the understanding of PROV-DM, and
possibly reconsider the implied activity. I don't remember us discussing
this at a WG level.

-- 
Stian Soiland-Reyes, myGrid team
School of Computer Science
The University of Manchester
Received on Monday, 3 September 2012 15:34:06 GMT

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