- From: Simon Miles <simon.miles@kcl.ac.uk>
- Date: Wed, 14 Dec 2011 10:46:13 +0000
- To: Provenance Working Group WG <public-prov-wg@w3.org>
+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. 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. 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 >>> >> > -- Dr Simon Miles Lecturer, Department of Informatics Kings College London, WC2R 2LS, UK +44 (0)20 7848 1166 Handling Mitigating Circumstances for Electronic Contracts: http://eprints.dcs.kcl.ac.uk/1283/
Received on Wednesday, 14 December 2011 10:46:42 UTC