W3C home > Mailing lists > Public > public-prov-wg@w3.org > December 2011

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

From: Stephan Zednik <zednis@rpi.edu>
Date: Wed, 14 Dec 2011 10:05:22 -0700
Cc: Provenance Working Group WG <public-prov-wg@w3.org>
Message-Id: <ADF79728-4CC4-4A75-8B4A-176261550BB7@rpi.edu>
To: Luc Moreau <L.Moreau@ecs.soton.ac.uk>
1: + 0.5 ( I am not sure about saying that the entity "did not exist" before the generation milestone, it seems to imply that the entity generation is instantaneous when all we are trying to say is that the milestone of entity generation is instantaneous.  Perhaps that the entity record is only accurate after the generation milestone?)
2: + 1
3: Use "milestone"

-- Stephan

On Dec 9, 2011, at 11:36 AM, 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.
> 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*. 
> 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

Received on Wednesday, 14 December 2011 17:08:23 UTC

This archive was generated by hypermail 2.4.0 : Friday, 17 January 2020 16:51:05 UTC