Re: Official OWL version outdated

Hi Holger

That makes sense as far as you make pretty clear that this is an
adaptation/translation, whatever you want to call it, from the original
schema.org RDFa, with slightly different semantics, not just a change of
format.

And the second topic - which is indeed larger - should not be hidden behind
this adaptation. The "loose" attachment of properties to classes proposed
by schema.org should be somehow clarified and specified. I've proposed a
first approach of such a specification in the OLCA vocabulary :
http://www.lingvoj.org/olca

Best regards

Bernard


2013/5/14 Holger Knublauch <holger@topquadrant.com>

>  Hi Bernard,
>
> the goal of my schema.org version was to be as friendly as possible to
> existing OWL/RDF tools. These existing tools have no idea what the
> properties schema:domain or schema:domainIncludes mean. Therefore I am
> using rdfs:domain. The topbraid version is not intended to be a 1:1 mapping
> of the official schema.org RDFa version - that already exists and people
> can use it if they prefer. I have left the schema:domain/range triples in
> my OWL version so that tools can consult those in addition to the rdfs:
> properties.
>
> Note that it's a different topic whether something like
> schema:domainIncludes should be standardized and used more widely - I agree
> that these might be more intuitive and extensible than the OWL work-around
> of owl:unionOf. But that's a larger topic...
>
> Regards,
> Holger
>
>
>
> On 5/14/2013 2:00, Bernard Vatant wrote:
>
>    Hi Holger
>
>  Nice try :)
>
>  I have comments on the redundant use of rdfs:domain, schema:domain.
> rdfs:range, schema:range.
> As explained quite a while ago by Dan and others, the way schema.orgbinds properties to classes is over-specified by rdfs:domain and
> rdfs:range, that's why the RDFa expression uses schema:domain and
> schema:range instead,
> But actually those properties themselves are not defined, but
> schema:domainIncludes and schema:rangeIncludes are defined.
>
>  So, seems to me all redundant declarations of rdfs:domain and
> schema:domain should be replaced by a single schema:domainIncludes, and all
> redundant declarations of rdfs:range and schema:range should be replaced by
> a single schema:rangeIncludes.
>
> For example instead of ...
>
> <owl:ObjectProperty rdf:about="http://schema.org/editor">    <rdfs:range rdf:resource="http://schema.org/Person"/>    <rdfs:domain rdf:resource="http://schema.org/CreativeWork"/>    <schema:range rdf:resource="http://schema.org/Person"/>    <schema:domain rdf:resource="http://schema.org/CreativeWork"/></owl:ObjectProperty>
>
>  declare the following ...
>
> <owl:ObjectProperty rdf:about="http://schema.org/editor">    <schema:rangeIncludes rdf:resource="http://schema.org/Person"/>    <schema:domainIncludes rdf:resource="http://schema.org/CreativeWork"/></owl:ObjectProperty>
>
>
>
> 2013/5/11 Holger Knublauch <holger@topquadrant.com>
>
>>  I have posted an up to date OWL version of schema.org at
>>
>>     http://topbraid.org/schema/
>>
>> which follows different OWL encoding conventions than the other RDF/OWL
>> version(s) that I have come across. The page above explains these
>> conventions and their motivation.
>>
>> Feedback appreciated - this is just a first version (with the RDFa file
>> as its starting point).
>>
>> Thanks,
>> Holger
>>
>>
>>
>> On 5/8/2013 11:43, Kingsley Idehen wrote:
>>
>> On 5/7/13 9:22 PM, Holger Knublauch wrote:
>>
>> On 5/8/2013 10:44, Dan Brickley wrote:
>>
>>
>>
>> On Wednesday, May 8, 2013, Holger Knublauch wrote:
>>
>>> Looking at the OWL version of schema.org at
>>>
>>>     http://schema.org/docs/schemaorg.owl
>>>
>>> I notice that this seems to be a rather old version, while the RDFa
>>> version
>>>
>>>     http://schema.org/docs/schema_org_rdfa.html
>>>
>>> seems to be more recent. (When) will the OWL version be fixed?
>>
>>
>>  Is it useful? what do you prefer? The use of OWL is pretty weak since
>> we're so flexible.
>>
>>
>> It's not very useful in its current form, yet I believe it can be made
>> very useful with a few changes. You guys are probably wasting an
>> opportunity to get more "semantic web" people on board. My guess is that
>> most OWL people look at both prominent online versions (the official one
>> and the one of rdfs.org) and walk away because they are rather unusable.
>>
>> Specifically, I would do the following transformations (and as an
>> exercise I have actually implemented the required SPARQL updates based on
>> the current OWL file):
>>
>> - Clean up the owl:unionOfs with one member
>> - Convert any usage of schema.org datatypes with xsd ones
>> - Convert rdfs:range (Number or String) to xsd:float
>>
>> Along with a simple instance data converter, the ontology could be
>> changed to
>> - Replace schema:Thing with owl:Thing
>> - Replace schema:name with rdfs:label
>> - Replace schema:description with rdfs:comment
>> - Delete schema:url (as it's basically the URI of the subject)
>>
>> Manual clean up should
>> - Add cardinality restrictions
>> - Declare owl:inverseOf relationships
>> - Mark outdated properties (such as the plural forms) as owl:deprecated.
>>
>> Could this info be made available anywhere in machine readable form? I am
>> pretty sure not only the RDF/OWL mapping could use this info.
>>
>>
>> Does rdf/xml vs rdfa (or json-ld etc) matter to you? What about the
>> choice of all in one big file vs per-term?
>>
>>
>> It would be good to be able to owl:import something. The RDFa version
>> does some things better than the OWL version, but not everything is
>> perfect: properties with multiple rdfs:domains should use owl:unionOf (I
>> guess RDFa has trouble representing this?).
>>
>> And of course why not have the URIs dereferencable as true linked data...
>> This should be a trivial feature to add for an organization that large.
>> Even if just to show that the people behind schema.org do care about the
>> semantic web community.
>>
>> I am tempted to create our own copy based on the distilled RDFa version
>> on some topbraid.org address because I believe there is much more
>> potential here.
>>
>>
>> Yes, there is and I encourage you to crack on if you have the time.
>> Basically, make your tweak and then just publish the revised document at
>> URL.
>>
>> One specific use case is that many of our customers build their own
>> ontologies with concepts that are reinvented all the time - Person, Address
>> etc. While our tooling is generic and can work with any ontology, it would
>> be better to ship our product with some starter ontology and I believe
>> schema.org could become the foundation of this. For this starter
>> ontology, we would define some customized forms and views, e.g. so that
>> addresses show street address above postal code etc. We could also define
>> some out of the box web services with typical queries, reports etc. Clearly
>> there are other product ideas in this space that the schema.org effort
>> could also benefit of. The more alignment of data the better for everyone.
>> Even if RDFa and Microdata will remain the vehicles of distributing
>> schema.org instance data, these web pages may be generated by a triple
>> store.
>>
>>
>> Not may, they will, and have been :-)
>>
>>
>> Sorry if this is repeating some discussions that have already happened
>> elsewhere... I am trying to catch up.
>>
>> HTH
>> Holger
>>
>>
>>
>> --
>>
>> Regards,
>>
>> Kingsley Idehen	
>> Founder & CEO
>> OpenLink Software
>> Company Web: http://www.openlinksw.com
>> Personal Weblog: http://www.openlinksw.com/blog/~kidehen
>> Twitter/Identi.ca handle: @kidehen
>> Google+ Profile: https://plus.google.com/112399767740508618350/about
>> LinkedIn Profile: http://www.linkedin.com/in/kidehen
>>
>>
>>
>>
>>
>
>
> --
> *Bernard Vatant
> *
> Vocabularies & Data Engineering
>  Tel :  + 33 (0)9 71 48 84 59
>  Skype : bernard.vatant
> Blog : the wheel and the hub <http://bvatant.blogspot.com>
>  --------------------------------------------------------
> *Mondeca**          **                   *
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>
>


-- 
*Bernard Vatant
*
Vocabularies & Data Engineering
Tel :  + 33 (0)9 71 48 84 59
Skype : bernard.vatant
Blog : the wheel and the hub <http://bvatant.blogspot.com>
--------------------------------------------------------
*Mondeca**          **                   *
3 cité Nollez 75018 Paris, France
www.mondeca.com
Follow us on Twitter : @mondecanews <http://twitter.com/#%21/mondecanews>
----------------------------------------------------------

Mondeca is selected to present at ReInvent Law,
London<http://reinventlawlondon.com/> on
June 14th

Mondeca will be supporting its client's
presentation<http://semtechbizsf2013.semanticweb.com/sessionPop.cfm?confid=70&proposalid=5127>
at
SemTech in San Francisco

 <http://semtechbizsf2013.semanticweb.com/sessionPop.cfm?confid=70&proposalid=5127>