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Re: PROV-ISSUE-239 (TLebo): is wasGeneratedBy(e) meaningful? [prov-dm]

From: Paolo Missier <Paolo.Missier@ncl.ac.uk>
Date: Tue, 07 Feb 2012 13:01:19 +0000
Message-ID: <4F31209F.2080906@ncl.ac.uk>
To: Daniel Garijo <dgarijo@delicias.dia.fi.upm.es>
CC: Timothy Lebo <lebot@rpi.edu>, "public-prov-wg@w3.org" <public-prov-wg@w3.org>
Daniel,

ok no objection in principle, in line with the incomplete nature of provenance -- but then 'wasGeneratedBy' is misleading, it should 
simply be 'wasGenerated'  or 'generation' -- some may have proposed this already and I may have missed it. I know Luc discussed this 
at least privately.
But note that this would then apply to use as well? I may know when something was used but not by whom, so "used" as in "a used e" 
would be misleading, and 'usage' more appropriate.
We just need to agree and then be consistent.

-Paolo

On 2/7/12 10:12 AM, Daniel Garijo wrote:
> Hi Paolo,
> what if instead of the time, I just knew the location (it was generated in Madrid),
> or the role of the activity (i.e., creator), but not the activity itself?
>
> Maybe we are running into a corner case, but as Stian suggested I don't see any reason
> why wasGeneratedBy([],e) should be forbidden.
>
> Now that I realize, we are not supporting this in prov-o!
>
> Daniel
>
> 2012/2/7 Paolo Missier <Paolo.Missier@ncl.ac.uk <mailto:Paolo.Missier@ncl.ac.uk>>
>
>     Tim
>
>     what I meant is that the def. should not make it optional.
>
>     wasGeneratedBy([],e) seems uninformative.
>
>     The argument that you could have a timestamp brings us back to the F2F discussion on separating "at" from "by" everywhere:
>
>     wasGeneratedAt(), wasGeneratedB(),
>     wasStartedAt(), wasStartedBy()
>     ...
>
>     -Paolo
>
>
>
>      On 2/7/12 1:20 AM, Timothy Lebo wrote:
>>     /
>>     /
>>
>>
>>
>>     On Feb 6, 2012, at 5:57 PM, Paolo Missier wrote:
>>
>>>     The activity should not be optional, surely?
>>
>>     But it is!
>>
>>
>>     All of the components except entity are optional, so DM lets me say "wasGeneratedBy(e)"
>>     /wasGeneratedBy(id,e,a,t,attrs)/
>>
>>       * /id/: an /optional/ identifier id identifying the generation record;
>>       * /entity/: an identifier e identifying an entity record that represents the entity that is created;
>>       * /activity/: an /optional/ identifier a identifying an activity record that represents the activity that creates the entity;
>>       * /time/: an /optional/ "generation time" t, the time at which the entity was created;
>>       * /attributes/: an /optional/ set of attribute-value pairs attrs that describes the modalities of generation of this entity
>>         by this activity.
>>
>>
>>     so the activity _must_ be there, and if it's not named then we _must_ name one?
>>
>>     If so, then how do we tell the difference between that kind of optional and the truly optional references?
>>
>>
>>
>>     -Tim
>>
>>
>>
>>
>>>
>>>     -Paolo
>>>
>>>     On 2/6/12 9:19 PM, Provenance Working Group Issue Tracker wrote:
>>>>     PROV-ISSUE-239 (TLebo): is wasGeneratedBy(e) meaningful? [prov-dm]
>>>>
>>>>     http://www.w3.org/2011/prov/track/issues/239
>>>>
>>>>     Raised by: Timothy Lebo
>>>>     On product: prov-dm
>>>>
>>>>     Everything but entity is OPTIONAL in wasGeneratedBy.
>>>>
>>>>     If I say only wasGeneratedBy(e), what did I say? And why was I allowed to say it?
>>>>
>>>>     from WD3:
>>>>
>>>>
>>>>     A generation record, written wasGeneratedBy(id,e,a,t,attrs) in PROV-ASN, has the following components:
>>>>
>>>>         id: an optional identifier id identifying the generation record;
>>>>         entity: an identifier e identifying an entity record that represents the entity that is created;
>>>>         activity: an optional identifier a identifying an activity record that represents the activity that creates the entity;
>>>>
>>>>
>>>>
>>>
>>>
>>>     -- 
>>>     -----------  ~oo~  --------------
>>>     Paolo Missier - Paolo.Missier@newcastle.ac.uk <mailto:Paolo.Missier@newcastle.ac.uk>, pmissier@acm.org <mailto:pmissier@acm.org>
>>>     School of Computing Science, Newcastle University,  UK
>>>     http://www.cs.ncl.ac.uk/people/Paolo.Missier
>>>
>>>
>>>
>>
>
>
>     -- 
>     -----------  ~oo~  --------------
>     Paolo Missier -Paolo.Missier@newcastle.ac.uk  <mailto:Paolo.Missier@newcastle.ac.uk>,pmissier@acm.org  <mailto:pmissier@acm.org>
>     School of Computing Science, Newcastle University,  UK
>     http://www.cs.ncl.ac.uk/people/Paolo.Missier
>
>


-- 
-----------  ~oo~  --------------
Paolo Missier - Paolo.Missier@newcastle.ac.uk, pmissier@acm.org
School of Computing Science, Newcastle University,  UK
http://www.cs.ncl.ac.uk/people/Paolo.Missier
Received on Tuesday, 7 February 2012 13:08:08 GMT

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