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Re: Proposals to vote on related to 'event': deadline Dec 14th midnight GMT

From: Luc Moreau <L.Moreau@ecs.soton.ac.uk>
Date: Wed, 14 Dec 2011 12:16:17 +0000
Message-ID: <EMEW3|7f96742c02e67032a62866fd094c88e1nBDCGN08L.Moreau|ecs.soton.ac.uk|4EE89391.6090709@ecs.soton.ac.uk>
To: public-prov-wg@w3.org
Dear all,
Thanks to those who have already voted.
This email acts as a reminder.
Cheers,
Luc

On 12/09/2011 06:36 PM, Luc Moreau wrote:
> Dear all,
>
> Several of you, including Satya, Tim and Jim have raised various
> concerns about events.  Here are some proposals to tackle these
> concerns in prov-dm WD3. Can you express your support in the usual
> way, we will confirm the outcome at the next teleconference.
>
> CONTEXT:
>
> 1. The concept of event as defined in prov-dm is instantaneous. On the
>    other hand, other ontologies define the concept of event, e.g. LODE
>    [1], as not instantaneous. This causes confusion, and risks
>    hampering adoption.
>
> 2. The prov-dm document (WD2) is defining 'generation' in a
>    conflicting manner.  On the one hand, in [2], it states that
>    generation is an event, so is instantaneous.  On the other hand, in
>    [3], it states that completion of generation is the event.
>
> In a generation, what we care about is the point at which the entity
> becomes available for consumption by others.  Before that, it's not an
> entity yet (or it is not this entity being generated).  So, calling
> the whole of generation an event (forget the choice of word for now)
> is not what was intended.  The event is the point at which generation
> is complete.
>
> This is actually nice reflected in Olaf and Jun's provenance
> vocabulary [4], where they have a similar concept, called Data
> Creation defined as:
>
>     DataCreation is a class that represents the completed creation of 
> a data item.
>
>
> Note the choice of word *completed*.
>
> PROPOSALS:
>
>
> We therefore propose to change the definition of Generation [2] as
> follows.
> - With proposals 1 and 2, resolve the conflicting definitions around 
> generation (and use) in prov-dm.
> - With proposal 3, adopt another name for event.
>
>
>
> PROPOSAL 1. Adopt the following Definition for generation.
> /In PROV-DM, a generation record is a representation of a
> world event, the completed creation of a new entity by an
> activity. This entity did not exist before this event; this entity is
> available for usage after this event./
>
>
> Comment: With this, we are not saying that creation of an entity is
> the event, it's the completed creation that is an event.  It's also
> also fine, I believe, to regard this as instantaneous.  Also, if
> somebody wants to model the actual creation, it is also fine, they can
> use activities for that.
>
> For usage, we would take a similar approach. In the provenance
> vocabulary, they use the completed access to a data structure, but
> this is not right for what we want. Instead:
>
> PROPOSAL 2. Adopt the following Definition for usage.
> /In PROV-DM, a usage record is a representation of a world
> event: the start of an entity consumption by an activity. Before this
> event, this entity was not consumed or used in any form or shape by
> the activity, totally or partially.
> /
> Comment: These definitions are now exactly in line with those in [3].
>
>
> /PROPOSAL 3. Replace the word event by action./
>
> Comment: So, prov-dm would define four actions: entity
> generation/entity usage/activity start/activity end, which are all
> instantaneous.  These actions would have "effects" on the system in
> the sense that they change the entities and activities it contains.
>
> Assuming proposal 3 is adopted, obviously, the text of proposals 1 and
> 2 would use the word 'action'.
>
>
> Can you express your support, or counter-proposals, by Wednesday 
> midnight GMT.
> Assuming there is support, we would incorporate all these changes 
> before XMas.
>
> Best regards,
>
>
> Luc
>
> [1] http://linkedevents.org/ontology/
> [2] 
> http://dvcs.w3.org/hg/prov/raw-file/default/model/ProvenanceModel.html#dfn-Generation
> [3] 
> http://dvcs.w3.org/hg/prov/raw-file/default/model/ProvenanceModel.html#types-of-events
> [4] http://trdf.sourceforge.net/provenance/ns.html#sec-DataCreationClasses
>

-- 
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 Wednesday, 14 December 2011 12:16:48 GMT

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