Re: Constraint V Refinement

Hi

I agree some more clarification or guidance would be useful in regard to
Constraints and Refinements, the distinction was one of the first
discussion points in our project.
However, which you use I suspect is domain/context dependent.

With the profile we are building at ITV, having spatial and  temporal
constraints on the Rule, i.e. as Constraints, makes a lot of sense as they
are the key indexes of the data, alongside the Action, we can narrow down
our search using just them before we get into the more complex Refinements
about the Action; which in our area can get quite complex.  We also opted
for Language being a Constraint on the Rule, which was not so clear cut but
we opted for it again as a key factor on finding appropriate permissions in
our database.

I note you also mention using 'Stream' as the Action, we have opted to have
a higher level Action i.e. Publish, and the media properties i.e. how you
publish, transmission, scheduling conditions, DRM, platforms, publishers
and so on, being restrictions as there is a long tail of these which will
continue to grow, whereas Publish is relatively stable.  This allows us a
clear split between Distribution/Selling of content (odrl:grantUse) and
Broadcast/Publish concepts.

Cheers,
James

On Fri, 8 Apr 2022 at 09:17, nicoletta.fornara@usi.ch <
nicoletta.fornara@usi.ch> wrote:

> Hi,
>
> I agree on the fact that we need a formal interpretation of the meaning of
> refinement and constraint!-)
>
>
> The fact that the delivery channel is a property of the action or a
> property of the asset depends on the application-dependent ontology that we
> want to use for representing the class of actions regulated by the policy..
>
>
> My intuition is that a video has not the property deliveryChannel.
>
> But for example the VideoObject class in Schema.org
> https://schema.org/VideoObject has the genre property that can be used to
> express the broadcast channel!
>
> Unfortunately, in Schema.org there is not a StreamAction class (but there
> is the WatchAction class with the service provider property).
>
>
> Regards
>
> Nicoletta
>
>
>
>
>
>
>
>
>
> ________________________________
> Da: Víctor Rodríguez Doncel <vrodriguez@fi.upm.es>
> Inviato: giovedì, 7 aprile 2022 16:20:27
> A: public-odrl@w3.org
> Oggetto: Re: Constraint V Refinement
>
> Hi,
>
> I do not see a great difference between refinement or constraint because
> its interpretation is not defined (cf. examples in a testbed where an
> algorithm must behave differently in each case), therefore the difference
> is only philosophical to me. And even in this case unclear: I would have
> said constraint, though, for the deliveryChannel, and if refinement,
> refinement of the action (this would be like an "adverb" modifying the
> action rather than an "adjective" qualifying the asset)
>
> Regards,
> Víctor
>
> > Is the deliveryChannel a refinement on ‘stream’ or a constraint on the
> rule?
>
> refinement on the asset i.e. the video itself? e.g., => "you can stream
> (action) videos whose deliveryChannel is YouTube (asset with
> deliveryChannel == YT)
>
> br, simon
>
> On Thu, 7 Apr 2022 at 02:42, Renato Iannella <r@iannel.la<mailto:
> r@iannel.la>> wrote:
>
> Hi all, we generally define the constraint property as a “condition on the
> rule” and the refinement property as “narrow the semantics of the action”.
>
> So, for example temporal and geospatial conditions apply to the rule, and
> printing at most 5 times is a refinement to print.
>
> My question is how to interpret this difference with other use cases, such
> as:
>  - you can stream (action) a video (asset)  on YouTube (deliveryChannel)
> only?
>
> Is the deliveryChannel a refinement on ‘stream’ or a constraint on the
> rule?
>
> Thanks…Renato
>
>
>
> --
> Víctor Rodríguez-Doncel
> D3205 - Ontology Engineering Group (OEG)
> Departamento de Inteligencia Artificial
> ETS de Ingenieros Informáticos
> Universidad Politécnica de Madrid
>
> Campus de Montegancedo s/n
> Boadilla del Monte-28660 Madrid, Spain
> Tel. (+34) 910672914
> Skype: vroddon3
> http://cosasbuenas.es
>
>
>