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Re: Even more Fuzzy about FunctionalProperty!

From: Mike Dean <mdean@bbn.com>
Date: Wed, 05 Mar 2003 05:57:14 -0800
Message-Id: <200303051357.FAA21079@escher.SD.BBN.COM>
To: "Roger L. Costello" <costello@mitre.org>
cc: www-rdf-logic@w3.org

> I am not real comfortable that you have completely
> answered my question, so let me followup with the example that you
> presented.

Other folks can probably express this more formally, but my
take is that #Joseph and #Joe are equivalent (i.e.
owl:sameIndividualAs).  An implementation could probably
then "merge" them, but it would often be preferable to link
the instances and follow the equivalence arcs during lookup.

> Since "hasFather" has been declared to be a FunctionalProperty can we
> infer that this:
> 
>         <Person rdf:ID="Joe">
>             <age>56</age>
>         </Person>
>
> is equivalent to this:
> 
>         <Person rdf:ID="Joseph">
>             <address>101 Curl Drive, Columbus, OH</address>
>         </Person>

#Joe is equivalent to #Joseph.  We haven't said anything
about the equivalence (e.g. owl:equivalentProperty) of #age
and #address.
 
> Thus, when inferencing do we treat the values of "hasFather" as a "black
> box", or must we "reconcile" the values?

I'm not sure what you mean by reconcile.  Remember that
these are all graphs rather than XML structure.

It would also be reasonable to conclude

  <Person rdf:ID="Joe">
    <age>56</age>
    <address>101 Curl Drive, Columbus, OH</address>
  </Person>

  <Person rdf:ID="Joseph">
    <age>56</age>
    <address>101 Curl Drive, Columbus, OH</address>
  </Person>

i.e. "merging" the statements about the instances.  This is
in fact implemented by the DAML+OIL layer in Jena.

	Mike
Received on Wednesday, 5 March 2003 08:57:18 GMT

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