PersonUsingTool implicit vs explicit

Hi,

In the current EARL 1.0 Schema [1], we implicitly define the "PersonUsingTool" class by the combination of the following:

 * it is one type of the "Assertor" class
 * it is the domain of the "UsingTool" property
 * it is the domain of the "user" property

[1] <http://www.w3.org/WAI/ER/EARL10/WD-EARL10-Schema-20050628.html#schema-rdf>

Besides leading to the fact that this construct allows several "user" and "UsingTool" properties to be used within a single "PersonUsingTool" class, the restrictions on FOAF:Person are defined twice making the schema rather confusing and ugly.

Please find below a proposal for discussion, here summary of the idea behind it:

 * an "Assertor" can either be a "Human" or a "Software" (dropped "PersonUsingTool" here)
 * a "Human" has exactly one "Person" property (I hear CMN and JL scream now)
 * a "Human" has any number of "UsingTool" property (thus, no need for another class to define people without tools)
 * property "UsingTool" remains unchanged
 * property "user" is to become "Person" with the range restrictions unchanged

Here is the code in RDF/XML:

  <rdfs:Class rdf:about="http://www.w3.org/WAI/ER/EARL/nmg-strawman#Assertor">
    <rdfs:label xml:lang="en">Assertor Class</rdfs:label>
    <rdfs:comment xml:lang="en">Person or evaluation tool that claims assertions</rdfs:comment>
    <owl:oneOf rdf:parseType="Collection">
      <owl:Thing rdf:type="http://www.w3.org/WAI/ER/EARL/nmg-strawman#Human"/>
      <owl:Thing rdf:type="http://www.w3.org/WAI/ER/EARL/nmg-strawman#Software"/>
    </owl:oneOf>
  </rdfs:Class>

  <rdfs:Class rdf:about="http://www.w3.org/WAI/ER/EARL/nmg-strawman#Human">
    <rdfs:label xml:lang="en">Person Assertor</rdfs:label>
    <rdfs:comment xml:lang="en">A person that can perform tests</rdfs:comment>
    <rdfs:subClassOf rdf:parseType="Collection">
      <owl:Restriction>
        <owl:onProperty rdf:resource="http://www.w3.org/WAI/ER/EARL/nmg-strawman#Person"/>
        <owl:minCardinality rdf:datatype="http://www.w3.org/2001/XMLSchema#nonNegativeInteger">1
          </owl:minCardinality>
        <owl:maxCardinality rdf:datatype="http://www.w3.org/2001/XMLSchema#nonNegativeInteger">1
          </owl:maxCardinality>
      </owl:Restriction>
      <owl:Restriction>
        <owl:onProperty rdf:resource="http://www.w3.org/WAI/ER/EARL/nmg-strawman#UsingTool"/>
        <owl:minCardinality rdf:datatype="http://www.w3.org/2001/XMLSchema#nonNegativeInteger">0
          </owl:minCardinality>
      </owl:Restriction>
    </rdfs:subClassOf>
  </rdfs:Class>

  <rdf:Property rdf:about="http://www.w3.org/WAI/ER/EARL/nmg-strawman#usingTool">
    <rdfs:label xml:lang="en">Using the tool </rdfs:label> 
    <rdfs:domain rdf:resource="http://www.w3.org/WAI/ER/EARL/nmg-strawman#Human"/> 
    <rdfs:range rdf:resource="http://www.w3.org/WAI/ER/EARL/nmg-strawman#Software"/> 
  </rdf:Property>

  <rdf:Property rdf:about="http://www.w3.org/WAI/ER/EARL/nmg-strawman#Person">
    <rdfs:label xml:lang="en">Using the tool </rdfs:label> 
    <rdfs:domain rdf:resource="http://www.w3.org/WAI/ER/EARL/nmg-strawman#Human"/> 
    <rdfs:range>
      <owl:Thing rdf:type="http://xmlns.com/foaf/0.1/Person">
        <rdfs:subClassOf rdf:parseType="Collection">
          <owl:Restriction>
            <owl:onProperty rdf:resource="http://xmlns.com/foaf/0.1/name"/>
            <owl:minCardinality rdf:datatype="http://www.w3.org/2001/XMLSchema#nonNegativeInteger">0
              </owl:minCardinality>
          </owl:Restriction>
          <owl:Restriction>
            <owl:onProperty rdf:resource="http://xmlns.com/foaf/0.1/mbox"/>
            <owl:minCardinality rdf:datatype="http://www.w3.org/2001/XMLSchema#nonNegativeInteger">0
              </owl:minCardinality>
          </owl:Restriction>
          <owl:Restriction>
            <owl:onProperty rdf:resource="http://xmlns.com/foaf/0.1/mbox_sha1sum"/>
            <owl:minCardinality rdf:datatype="http://www.w3.org/2001/XMLSchema#nonNegativeInteger">0
              </owl:minCardinality>
          </owl:Restriction>
        </rdfs:subClassOf>
      </owl:Thing>
    </rdfs:range>
  </rdf:Property> 


Regards,
  Shadi


-- 
Shadi Abou-Zahra,     Web Accessibility Specialist for Europe 
Chair and Team Contact for the Evaluation and Repair Tools WG 
World Wide Web Consortium (W3C),           http://www.w3.org/ 
Web Accessibility Initiative (WAI),    http://www.w3.org/WAI/ 
WAI-TIES Project,                 http://www.w3.org/WAI/TIES/ 
Evaluation and Repair Tools WG,     http://www.w3.org/WAI/ER/ 
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Received on Monday, 11 July 2005 09:42:43 UTC