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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 12:52:06 +0000
Message-ID: <EMEW3|a55727b11c32b55d17d6136759dba295nBDCqA08L.Moreau|ecs.soton.ac.uk|4EE89BF6.9080508@ecs.soton.ac.uk>
To: public-prov-wg@w3.org
Hi Simon,

Response interleaved.

On 12/14/2011 10:46 AM, Simon Miles wrote:
> +1 for Proposal 1
> +1 for Proposal 2
> -1 for Proposal 3, as I find "event" a lot clearer than "action"
>
> Reasons why I think Proposal 3 is unnecessary:
>
> As far as I understood from earlier discussion, the problem with the
> term "event" was that an event is not intuitively instantaneous,
> outside of special usage in process algebra etc. I also argued on a
> separate thread on Prov-O that "being instantaneous" was something
> that could never be honestly asserted, as what is instantaneous for
> one asserter may be decomposed by another. We cannot force asserters
> to give the time an event occurs to a second if they only know it at
> the granularity of a day, and even if they could, many other events
> may be separately asserted to happen at different points during that
> second.
>    

I think you are mixing imprecision in the measure and the fact that
an event is instantaneous.

> Proposals 1 and 2 seem to remove the requirement that the events be
> instantaneous, so Proposal 3 seems unnecessary. You did say, "It's
> also also fine, I believe, to regard this as instantaneous", but I
> take this to imply it is also fine to regard an event as
> non-instantaneous? I can't see we lose anything by this flexibility.
>
>    
I didn't mean this to be optional. I think that proposal 1 and 2 make
it clear that it's instantaneous.

Satya's alternative suggestion of an 'instantaneous event' is also
good for me. (Easier to implement, and closer to the orignal proposal)

Luc

> Thanks,
> Simon
>
> On 14 December 2011 10:20, Daniel Garijo<dgarijo@delicias.dia.fi.upm.es>  wrote:
>    
>> +1 for proposals 1 and 2.
>> +1 for proposal 3. As long as we agree on what we are dealing with, I don't
>> have anything against using another name.
>> And if we can avoid confusion with other ontologies, then even better.
>>
>> Best,
>> Daniel
>>
>>
>> 2011/12/10 Satya Sahoo<satya.sahoo@case.edu>
>>      
>>> +1 for proposal 1
>>> +1 for proposal 2
>>> -1 for proposal 3 (I believe explicitly stating instantaneousEvent is
>>> better option than re-labeling as action. Action, similar to event, has
>>> multiple connotations including instantaneous and long running)
>>>
>>> Best,
>>> Satya
>>>
>>>
>>> On Sat, Dec 10, 2011 at 12:50 AM, Reza B'Far (Oracle)
>>> <reza.bfar@oracle.com>  wrote:
>>>        
>>>> +1 on Proposal 1.  I think this actually resolves 2 other issues I
>>>> brought up a couple of months ago (but let go) -- providing an "origination
>>>> time" which is important in legal/financial applications as well as making a
>>>> distinction between the very first time something is created vs. the
>>>> subsequent times (for example, ratification of a law).  Anyways, great
>>>> proposal.  I realize the nuance in the comment is a bit different than what
>>>> I'm saying, but it doesn't matter.  There is now some mechanism to solve
>>>> what I need :)
>>>>
>>>> +0 on Proposal 2.  Clear semantics and good proposal to understand, but I
>>>> think the verbiage is awkward for beginners.  I could change to +1 if the
>>>> verbiage is made easier.
>>>>
>>>> +1 on Proposal 3 conditional on going through Prov-DM and assuring that
>>>> we don't use the words "actions" or "action" in any other context in the
>>>> examples, etc. [hope that makes sense]
>>>>
>>>>
>>>>
>>>> On 12/9/11 10:36 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.
>>>>
>>>> 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 12:55:08 GMT

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