Re: question on constraint 47 (3) - wasAssociatedWith-ordering

Hi Paul,

Constraint 47 is looking at the ordering constraints between
an activity a and an agent ag, considering
- ag is an entity (cases 1 and 2)
- ag is an activity (cases 3 and 4)

Case 3 says that the agent (an activity) must have ended after the start of
the activity a, ensuring some overlap between the two.

Luc

On 01/16/2013 09:44 AM, Paul Groth wrote:
> Hi All,
>
> Can someone clarify the following in the spec (Constraint 47 - 3)
>
> IFwasAssociatedWith(_assoc; a,ag,_pl,_attrs) and wasStartedBy(start1; 
> a,_e1,_a1,_t1,_attrs1) and wasEndedBy(end2; 
> ag,_e2,_a2,_t2,_attrs2)THENstart1precedes 
> <http://www.w3.org/TR/prov-constraints/#dfn-precedes>end2.
>
>
> From my reading, this is saying that the start of activity a, must 
> happen after the end of activity, a2 if the the agent, ag, ended 
> activity a2.
>
> This doesn't make sense to me. An agent can  potentially end one 
> activity and start another...
>
> Can someone clarify this for me?
>
> Thanks
> Paul

-- 
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
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