- From: Graham Klyne <GK@ninebynine.org>
- Date: Tue, 12 Jul 2011 17:02:23 +0100
- To: Simon Miles <simon.miles@kcl.ac.uk>
- CC: Provenance Working Group WG <public-prov-wg@w3.org>
Simon Miles wrote: > To understand the consequences of the above points, I suggest > alternative definitions at the link below: > http://www.w3.org/2011/prov/wiki/Talk:F2F1ConceptDefinitions#Entity_and_IVP_of +1 I think this is a big improvement over what we have. #g -- Simon Miles wrote: > Hello, > > I raised a point with Luc and Jim (McC) at the F2F1, but did not have > time to mention it in discussion. It primarily concerns the definition > of Thing/Stuff/Entity/Entity State/BOB. > > I think complexity and confusion arises from talking about "modelling" > and "representing" in the model itself. The concepts comprising a > model should be just whatever is modelled, e.g. "process execution", > not how the model is used, e.g. "representation of a process > execution". > > It should already be clearly understood by users, but can be stated > explicitly, that in using any model you are asserting something about > whatever is modelled using some representation of it. We may also add > that any assertion is by necessity from some perspective, of which > there may be many, and not necessarily objectively true. These points > are separate from any concept definition. > > A connected point is that definitions in models will use colloquial > synonyms to get across what a concept is, and these do not need to be > defined, e.g. we do not define "activity" even though we say "a > process execution is an activity..." > > I think we got the above wrong for Thing, in saying: > "things represent real-world stuffs and have properties modeling > aspects of stuff states" > changed to: > "BOBs represent real-world entities and have properties modeling > aspects of entity states" > > First, this definition uses terms "represent" and "modeling", implying > it is about the use of the model not what is modelled. Second, the F2F > discussion ended up with "entity", the replacement of "stuff", being > treated as a concept in the model itself rather than a colloquial > synonym used for the purpose of definition, e.g. we discussed whether > an agent is an entity or an entity state (or a BOB). > > I argue we should be clear that there is only one concept being > defined here not two, and it is something in the world not a > representation of it. If we need to, we can say how users should apply > the model in accompanying notes. > > A similar problem may affect the IPV-of definition, where properties > are referred to having "corresponding" values. I think they have the > *same* values, which may be represented in different ways. The former > is a constraint of the model, while the latter is a given truth about > the use of any model. > > To understand the consequences of the above points, I suggest > alternative definitions at the link below: > http://www.w3.org/2011/prov/wiki/Talk:F2F1ConceptDefinitions#Entity_and_IVP_of > > Thanks, > Simon >
Received on Tuesday, 12 July 2011 16:03:09 UTC