Re: PROV-ISSUE-122: Constraint on wasGeneratedBy (PROV-DM and PROV-OM) [Conceptual Model]

Hi all,
There is an issue with the second constraint on wasGeneratedBy, hence I am
combining this with the first constraint on wasGeneratedBy.

Constraint (in PEOV-DM document on Oct 10, 2011):
"An entity e may be generated before the end of pe, for example a
manufacturing PE can generate multiple entities before terminating."

Issue: An entity e may be generated before the end of pe, for example a
manufacturing PE can generate multiple entities before terminating.

Thanks.

Best,
Satya

On Sun, Oct 9, 2011 at 7:36 PM, Provenance Working Group Issue Tracker <
sysbot+tracker@w3.org> wrote:

>
> PROV-ISSUE-122: Constraint on wasGeneratedBy (PROV-DM and PROV-OM)
>  [Conceptual Model]
>
> http://www.w3.org/2011/prov/track/issues/122
>
> Raised by: Satya Sahoo
> On product: Conceptual Model
>
> The following constraint is defined on wasGeneratedBy in the PROV-DM
> document (as on Oct 9, 2011):
> "Given a process execution pe, entity e, role r, and optional time t, if
> the assertion wasGeneratedBy(e,pe,r) or wasGeneratedBy(e,pe,r,t) holds, the
> values of some of e's attributes are determined by the activity denoted by
> pe and the entities used by pe. Only some (possibly none) of the attributes
> values may be determined since, in an open world, not all used entities may
> have been asserted."
>
> Issue: This constraint seems to be self-contradictory due to the two
> phrases "...the values of some of e's attributes are determined by the
> activity denoted by pe..." and "Only some (possibly none) of the attributes
> values may be determined...".
>
> In addition, this constraint cannot be enforced, since which attributes
> will be determined are not specified and given the use of open world
> assumption, there be always some attribute that is not currently associated
> with the entity.
>
> Overall, this constraint does not help either in inferring new knowledge
> from existing information or allow "validation/checking" of existing
> knowledge - which are the standard uses of rules/constraints. Hence, the
> suggestion is to remove this constraint.
>
>
>
>