URIs in my predicates for others' properties

I have some questions about URIs to use when representing properties whose
names and URI status are out of my control.

Let's say that there's a metadata standard called xyz, and they've
declared a schema somewhere. My document at
http://www.snee.com/docs/mydoc1.xml, which uses this standard, starts like
this:

  <document ns:xyz="http://www.xyz.org/schemas/docmetadata/">
    <xyz:header>
      <xyz:foo bar="56H">northwest</xyz:foo>
    </xyz:header>

I feel confident that the following triple makes sense:

  <http://www.snee.com/docs/mydoc1.xml>
  <http://www.xyz.org/schemas/docmetadata/foo>
  "northwest".

Confident, that is, unless xyz:foo shows up in another context in the same
document with a different value, in which case I want two different
triples to distinguish the two values.

A somewhat related issue: bar is not in any namespace, so it doesn't feel
right to create a predicate for it that begins with
http://www.xyz.org/schemas/docmetadata/.

Is the best practice for defining URIs for such information to just make
up my own URI for its predicate around a domain name that I have control
over, e.g. http://www.snee.com/ns/xyz/bar, and then use OWL to define an
equivalence if the xyz.org people (or anyone else) define their own URI
and triples for bar and I want to aggregate their triples with mine?

I'm guessing that this is the case based on the output of the MIT Simile
RDFizer project's RDF version of a sample MODS document. The MODS URI
http://www.loc.gov/mods/v3 doesn't show up anywhere in the RDFizer
representation of the MODS data, and most properties are in the namespace
http://simile.mit.edu/2006/01/ontologies/mods3#.

(I just made up xyz.org as I wrote this, and just now looked at
it--they're concerned with bigger issues than namespace URIs, such as the
Knights Templar and the Secrets of the Bible.)

thanks,

Bob

Received on Thursday, 4 January 2007 22:17:01 UTC