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Re: PROV-ISSUE-337 (agent-and-entity): agent should not be a subclass of entity [prov-dm]

From: Curt Tilmes <Curt.Tilmes@nasa.gov>
Date: Mon, 16 Apr 2012 06:13:11 -0400
Message-ID: <4F8BF0B7.90905@nasa.gov>
To: <public-prov-wg@w3.org>
Ok, I can see with your example that tying one activity to
another is useful.

That still doesn't convince me that the activity itself is
the agent.

Is there some other way we could tie an activity to another
activity that wouldn't require making the activity itself
an agent?

If the simplest way to model that would be to make the
activity an agent, I would support it.  (i.e. If other
ways to model that relationship add too much complexity,
I'd rather keep it simple and just say an activity can
be an agent.)

Curt

On 04/15/2012 11:13 AM, Miles, Simon wrote:
> Hello Curt,
>
> I think it may be more than that (though I realise I didn't convey this well). Yes, saying that an action is responsible for something does imply that the action was performed by a hidden entity that was 'really' responsible. But it also says more: that it is that particular action that was responsible, and not anything else the entity did.
>
> With all agents being entities, I can say:
>
> touchFileX wasAssociatedWith UnknownPerson
> backupFileX wasInformedBy touchFileX
> and maybe also
> backupFileX wasAssociatedWith UnknownPerson
>
> But what this does not express is that UnknownPerson did touchFileX so that backupFileX would happen. UnknownPerson might have done many things and, while backupFileX was caused by touchFileX, that might be coincindental.
>
> If I can say:
>
> backupFileX wasAssociatedWith touchFileX
>
> then it's clear that touchFileX was responsible for backupFileX occurring, i.e. the intent was behind touchFileX.
>
> I share your wariness about activities being agents and I'm not completely convinced myself, even given my examples. However, I also think that by allowing agents to be activities we are not, as with some past debates, getting influenced by contrived corner use cases, but rather just being less restrictive on how people model things when there's no benefit to doing so.
>
> thanks,
> Simon
>
> Dr Simon Miles
> Senior Lecturer, Department of Informatics
> Kings College London, WC2R 2LS, UK
> +44 (0)20 7848 1166
>
> Mapping Dublin Core to the Open Provenance Model:
> http://eprints.dcs.kcl.ac.uk/1386/
> ________________________________________
> From: Curt Tilmes [Curt.Tilmes@nasa.gov]
> Sent: 15 April 2012 15:34
> To: public-prov-wg@w3.org
> Subject: Re: PROV-ISSUE-337 (agent-and-entity): agent should not be a subclass   of entity [prov-dm]
>
> On 04/15/2012 10:17 AM, Miles, Simon wrote:
>> Curt:
>>> I'm suggesting that agents should be just entities and not activities.
>>> I'd like to see a good case where an activity is an agent.
>>
>> Maybe when the activity is an action with an intention behind it and
>> we don't wish to model who held the intention and performed the
>> action, just the action itself. Doing "touch file.x" was responsible
>> for "file.x being backed up", not just a cause of it. "Saying 'shut
>> the window'" was responsible for the activity of the window being
>> shut. regardless of who said it. Modelling the activities as agents
>> and using wasAssociatedWith allows the responsibility to be
>> expressed and so blame to later be ascribed.
>
> So the activity performed or directed by a 'hidden agent' is a
> modelled as a proxy for that agent, in place of actually expressing
> that agent.
>
> You still aren't suggesting that the activity *is* the agent, just
> that we use it as an agent in place of one we don't know about yet.
>
> I guess that is ok, but I really don't see the problem with just
> making up a largely undescribed agent as a placeholder to describing
> that agent more fully in the future.
>
> Curt
Received on Monday, 16 April 2012 10:13:43 GMT

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