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Re: EARL Schema resorted and with OWL constraints

From: Charles McCathieNevile <chaals@opera.com>
Date: Fri, 10 Jun 2005 18:33:12 +0200
To: shadi@w3.org
Cc: public-wai-ert@w3.org
Message-ID: <op.sr5xlmezwxe0ny@widsith.local>

More comments inline (some stuff deleted where I think we are in agreement)

On Fri, 10 Jun 2005 11:17:42 +0200, Shadi Abou-Zahra <shadi@w3.org> wrote:

> Charles McCathieNevile wrote:
>> Assertor:
>>  I am not sure that we should be setting a maximum cardinality on the   
>> properties of Assertor. We might want to block certain pairwise or  
>> n-ary  combinations, but I think there are good use cases for being  
>> able to have  more than one of many properties.
>
> Do you have suggestions for these combinations?

Hmm. I wrote about some in a mail on putting things together. I am not  
able to sit down and enumerate the combinations exhaustively at the moment  
- and I am not sure that we should try to do that.

>> I don't think we should make OWL constraints on foaf:Person.
>
> Had a tough time with this one so as to not redefine foaf:Person. It say  
> an earl:Assertor is either an earl:Tool a foaf:Person *with* specific  
> attributes, not that a foaf:Person *has* specific attributes. Were do  
> you see foaf:Person being redefined?

   <owl:Thing rdf:about="&foaf;Person">
       <rdfs:subClassOf rdf:resource="&rdfs;Resource"/>
       <rdfs:subClassOf>
         <owl:Restriction>
           <owl:onProperty rdf:resource="&foaf;name"/>
           <owl:minCardinality  
rdf:datatype="&xsd;nonNegativeInteger">1</owl:minCardinality>
         </owl:Restriction>

I think this is making statements about foaf:Person - if the owl:Thing  
were anonymous, of rdf:type foaf:Person then we would be OK.

As a new comment, we should only insist on at least one of foaf:mbox or  
foaf:mbox_sha1

>> Tool:
>>  I don't think we should have maxcardinality on versioning info, and   
>> probably not mincardinality either. In some cases we will want to have  
>> a  tool which just has a name, and other cases we will want a tool the   
>> isVersionOf that tool...
>
> Agree with the minCardinality part (version info should be optional).  
> However, how can a tool have more than one version?

Well, Hera has 2 versions. Microsoft Word has dozens. Opera has hundreds...

>> Again, we should not specify domain/range constraints on DCs terms. I   
>> don't think we need to make our own. In the spec we should just have   
>> examples of how thesee ought to be used in EARL.
>
> We agreed in the requirements to formalize EARL so this rules out  
> relying on descriptions in the spec... Having said that, we should try  
> to minimize the requirements on EARL parsers/processors.

There is a question about what we require of EARL processors. If we simply  
require them to be RDF processors then there is no problem if they deal  
with arbitrary RDF, so anything optional from another spec doesn't need to  
be defined. If we want to specify what terms a tool must recognise even if  
it is not an RDF processor and allow that tool to claim to be a valid EARL  
processor then we need to do it in a seperate conformance requirement.

Anyway, we should not define domain/range for dc properties, which the  
current proposed schema does in the Tool section.

>> TestMode:
>>  I am happy if the instance values are only defined in OWL, since that  
>> is  (IIRC) inheritable via RDFS.
>
> Down-side is compatibility with plain RDFS. I'm still working on that  
> one.

Well, IIRC OWL provides (in this case) compatibility with plain RDFS.

>> The label on heuristic should be "inference" since that is what it   
>> actually is.
>
> So that one too. Why not have heuristic *and* inference?

IMHO, because heuristic is just a complicated way of saying automated :-)

>> I think it is reasonable to have it for dc:description as well. We  
>> should  not ahve a maxCardinality - for example in teh development plan  
>> of Hera we  will be putting multiple descriptions on automated tests,  
>> to label in  different languages (since it is a multilingual tool).
>
> dc:description only has a minCardinality, not maxCardinality.

Right. I think it is important to keep that. I also think the  
mincardinality should be 0, not 1.

cheers

Chaals

-- 
Charles McCathieNevile                              chaals@opera.com
          hablo español - je parle français - jeg lærer norsk
   Here's one we prepared earlier:   http://www.opera.com/download
Received on Friday, 10 June 2005 16:33:21 GMT

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