Re: Asset as superclass of Policy / Asset not superclass of Policy. Asset same as Thing.

And I must apologize for my inexperience at writing in mailing lists.
Do you read me well if I use formatted text? Should I stop using HTML in 
the mailing list?

Regarding the "rdfs:range", this time the specification is clear:
http://www.w3.org/TR/rdf-schema/#ch_range

(but one learns it rather with experience).
The red font in the quotation below is mine (if you manage to read 
formatted text...).

Regards,
Víctor


            3.1 rdfs:range

    |rdfs:range|is an instance of|rdf:Property|
    <http://www.w3.org/TR/rdf-schema/#ch_property>that is used to state
    that the values of a property are instances of one or more classes.

    The triple

        P rdfs:range C

    states that P is an instance of the class|rdf:Property|
    <http://www.w3.org/TR/rdf-schema/#ch_property>, that C is an
    instance of the class|rdfs:Class|
    <http://www.w3.org/TR/rdf-schema/#ch_class>and *that the resources
    denoted by the objects of triples whose predicate is P are instances
    of the class C*.






El 29/07/2013 11:02, Mo McRoberts escribió:
> On  2013-Jul-29, at 09:50, V?ctor Rodr?guez Doncel <vrodriguez@fi.upm.es>
>   wrote:
>
>> My answer below...
>>
>> El 27/07/2013 9:51, Mo McRoberts escribi?:
>>> On 26 Jul 2013, at 14:36, V?ctor Rodr?guez Doncel <vrodriguez@fi.upm.es>
>>>   wrote:
>>>
>>>
>>>> Well, of course Asset must exist. But your sentence...
>>>> The act of associating a policy with it is what defines it as an ODRL asset.
>>>> ...can be represented very simply and elegantly, with just three statements:
>>>>
>>>> <Asset> rdf:type owl:Class .
>>>> <vocab:target> rdf:type owl:ObjectProperty ;
>>>>            rdfs:range <Asset> .
>>>>
>>>> Everything that is related to with a "vocab:target" is automatically inferred to be an Asset.
>>>>
>>> That does not infer that, though, does it?
>>>
>> Yes, it does :)
>>> That says that everything related with vocab:target *must be defined as* an Asset; to specify a vocab:target being an instance which was not explicitly stated as being an Asset would be a violation of the schema.
>>>
>> No, it isn't :) . Whatever it is, the instance will be classified as an Asset. Without you to declare it, without clashing with your previous class declarations.
> I must confess I'm not entirely understanding that: how does specifying that the range of vocab:target cause that inference? Isn't a range a constraint, rather than an implication?
>
>
>>>> Or even more exactly:
>>>>
>>>> <Asset> rdf:type owl:Class ;
>>>>           owl:equivalentClass [ rdf:type owl:Restriction ;
>>>>                                 owl:onProperty [ owl:inverseOf <vocab:target> ] ;
>>>>                                 owl:someValuesFrom owl:Thing
>>>>                               ] .
>>>>
>>>> Which can be read: "Everything that is range of a vocab:target, and only what is in range of a vocab:target, is an Asset".
>>>> At your choice.
>>>>
>> This alternative declares that Assets are only such if bound through the vocab:target. I'd say this is over-restrictive and we don't need this.
> Hm, as above: I don't quite follow how declaring a *restriction* brings about an *implication*?
>
> I'll cheerfully confess I'm no OWL guru, but I'd like to get my head around how this works!
>
> M.
>


-- 
Víctor Rodríguez-Doncel
D3205 - Ontology Engineering Group (OEG)
Departamento de Inteligencia Artificial
Facultad de Informática
Universidad Politécnica de Madrid

Campus de Montegancedo s/n
Boadilla del Monte-28660 Madrid, Spain
Tel. (+34) 91336 3672
Skype: vroddon3