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Re: PROV-ISSUE-19: is this observable or not observable?

From: Khalid Belhajjame <Khalid.Belhajjame@cs.man.ac.uk>
Date: Tue, 07 Jun 2011 19:32:06 +0100
Message-ID: <4DEE6EA6.2060606@cs.man.ac.uk>
To: Paolo Missier <Paolo.Missier@ncl.ac.uk>
CC: public-prov-wg@w3.org
Hi Paolo

>
> it's a good start, in that it subsumes observing value of data, and 
> therefore the state of a database, for example.
> But we also need to observe /events/, don't we. For example, data that 
> moves along a communication channel that connects two processors. 
> Someone forwarding an online post. Or  responding to the post.

  I was wondering if, instead, 'events' can be seen as a means for 
observing (or monitoring) changes, in particular changes in state.
Would that be fair?

khalid

>
> Also, in abstract, consider a state machine, "how did the machine 
> reach state S" is a legitimate provenance query (methinks). Then I 
> guess you may want to observe state transitions?
>
> I see two possible complications:
>  - not all transitions are observable (completeness of provenance)
>  - observers may be unreliable (correctness of provenance)
>
> --Paolo
>
> On 6/7/11 7:51 AM, Carl Reed wrote:
>> For what its worth, the following definitions are from several ISO 
>> documents
>> for Observations and Measurements - which relate directly to the 
>> semantics
>> of observable properties, such as for sensors.
>>
>> observation
>>
>> act of observing a property
>>
>> NOTE          The goal of an observation may be to measure or otherwise
>> determine the value of a property
>>
>> property
>>
>> facet or attribute of an object referenced by a name
>>
>> [ISO 19143:2010, definition 4.21]
>>
>> EXAMPLE                              Abby's car has the colour red, 
>> where
>> "colour red" is a property of the car instance
>>
>> And the one I enjoy: Observable - ability to be observed, possible to
>> observe, and so forth. The use of "observable" in physics and quantum
>> mechanics is very specific but essentially a sub-class of the general
>> definition.
>>
>> Anyway, observables are properties such as "temperature", "height",
>> "colour", "material".
>>
>> Cheers
>>
>> Carl
>>
>> ----- Original Message -----
>> From: "Paul Groth"<pgroth@gmail.com>
>> To: "Luc Moreau"<L.Moreau@ecs.soton.ac.uk>
>> Cc:<public-prov-wg@w3.org>
>> Sent: Tuesday, June 07, 2011 1:11 AM
>> Subject: Re: PROV-ISSUE-19: is this observable or not observable?
>>
>>
>>> Hi All,
>>>
>>> Can someone attempt to provide a clean notion of what observable and
>>> non-observable mean in this context.
>>>
>>> Thanks,
>>> Paul
>>>
>>> On Tue, Jun 7, 2011 at 9:00 AM, Luc Moreau<L.Moreau@ecs.soton.ac.uk>
>>> wrote:
>>>> Dear all,
>>>>
>>>> When we discussed the notion of 'Invariant View or Perspective on a
>>>> Thing,
>>>> there were
>>>> suggestions that it should be observable, and counter-suggestions 
>>>> that it
>>>> should not be.
>>>>
>>>> It would be good to discuss both sides of the argument, in an 
>>>> attempt to
>>>> reach consensus.
>>>>
>>>> Best regards,
>>>> Luc
>>>>
>>>>
>>>>
>>>>
>>>
>>
>
>
Received on Tuesday, 7 June 2011 18:32:50 GMT

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