- From: Jim Hendler <hendler@cs.umd.edu>
- Date: Tue, 24 Sep 2002 21:57:24 -0400
- To: "Smith, Michael K" <michael.smith@eds.com>
- Cc: webont <www-webont-wg@w3.org>
Mike - as a way to review the OWL in the guide document, I decided to
use it to explain OWL to my graduate semantic web class (explaining
to them we were reviewing the document which was very much in
progress). Short summary is we found tons of syntax errors, but
overall found it a useful document and an improvement on the previous
walkthru in some ways.
This review was of the September 18th version [1], apologies if there
is one later than this.
Meta comments-
History - problematic as is - Peter's changes, my changes to his
changes, and Leo's changes to my changes to his changes should all be
mentioned (OML doesn't actually need to be included - it never
actually got implemented, but XOL did)
Wine thread -
the students and I all liked the fact the example ran through the
document, However, those cases where it didn't (property
characteristics and restrictions, for example) were somewhat jarring
- probably be better to find examples for those we can (not that
important, but improves readability).
owl:individual -
With due respect, there's no such thing -- in the features document
individual is there as a descriptive term - as I understand OWL, we
do not say:
><owl:Individual ID="CENTRAL-COAST">
> <type rdf:resource="#CALIFORNIA-REGION"/>
> </owl:Individual>
but rather
<CALIFORNIA-REGION rdf:id="CENTRAL-COAST" />
(and when the definition contains other properties it looks like)
<CAL-REGION rdf:about="http://foo.bar.baz#CAL-COAST">
<cal-location>WEST</cal-location>
</CAL-REGION>
(see [2] for other, more complex examples of an individual.)
Consistency
there's a lot of inconsistency in capitalization (owl:ontology and
owl:Ontology for example) and also some typos like:
> <owl:Class rdf:ID="CABERNET-SAUVIGNON">
> <rdfs:subClassOf>
> <rdfs:subClassOf rdf:about="#WINE"/>
> </rdfs:subClassOf>
which is incorrect - you don't need the extra subclass level.
When this document is further along, it will need a VERY thorough
scrub of the RDF/OWL (Ora Lassila is great at this - maybe we could
recruit him?)
OneOf
I think the use of owl:thing in your OneOf example is legal, but I
think the preferred form is to reflect the property name -- that is,
in the DAML walkthru the example
><daml:Class rdf:ID="Height">
> <daml:oneOf rdf:parseType="daml:collection">
> <Height rdf:ID="short"/>
> <Height rdf:ID="medium"/>
> <Height rdf:ID="tall"/>
> </daml:oneOf>
></daml:Class>
is the preferred way.
Again, sorry to pick so many nits - overall the document is a good
contrbution, shows off the key language features and has a better mix
of instances and classes than the DAML walkthru did.
[1]
http://lists.w3.org/Archives/Public/www-webont-wg/2002Sep/att-0257/01-Guide.html
[2] http://www.cs.umd.edu/~hendler/jhendler.daml
--
Professor James Hendler hendler@cs.umd.edu
Director, Semantic Web and Agent Technologies 301-405-2696
Maryland Information and Network Dynamics Lab. 301-405-6707 (Fax)
Univ of Maryland, College Park, MD 20742 240-731-3822 (Cell)
http://www.cs.umd.edu/users/hendler
Received on Tuesday, 24 September 2002 21:57:32 UTC