Using a domain for a property will only be a problem if disjoints are stated. Even more, someone else could add further domains to trigger further rdfs:type inferences.
We should be careful, nonetheless, when using domains.
I'm saying this cause the word "constraint" does not quite represent what a domain is, and we should avoid it, since it creates confusion on OWL newcomers.
Very good point though.
On og., 2011.eko apiren 28a 22:14, Bob Morris wrote:
I´ve been in Ecuador for two weeks with only a few hours of internet contact. Flying from Quite tonight. So I´ve only scanned the Design Document and may have done so too hastily. I´ll have more time next week to look at it and the ontology. However, meanwhile, I´ve posted the following unsurprizing comment there, and hope that anyone who responds here will also respond there.
It´s a little hard to understand why DSW object properteries should have domains but data properties should not. Keep in mind that the formal semantics of rdfs:domain is that if rdfs:domain P C then any use a P x forces a to have rdfs:type C. This constrains the extensibility of P and probably of the use of other ontologies where P might be useful. Specifying domains tends to close the world somewhat, and I see no advantage to that....Indeed, this is more naughty than anti'naughty sensu Bob Morris.
--Bob Morris
On Wed, Apr 27, 2011 at 9:01 PM, Steve Baskauf steve.baskauf@vanderbilt.edu wrote:
Dear colleagues,
With the exciting development of Semantic Web technologies, many of us already need a way to consistently express DwC in RDF. In particular, we need it to meet the requirements for GUID resolution (as expressed in the TDWG applicability guide) and to be able to share and aggregate diverse kinds of biodiversity metadata in the Linked Open Data world.
After several months of development, stimulated by the tdwg-content discussions of last Fall, we would like to offer an ontology for consideration, based on Darwin Core terms:
Darwin-SW: General site: http://code.google.com/p/darwin-sw/ Using namespace dsw = "http://purl.org/dsw/"
It is a candidate for general usage, but we do not claim it is _the_ solution, and greatly respect the efforts by others to develop similar ontologies, from which we have learned much. However, for DSW, we wanted to use existing DwC terms for classes and data properties whenever possible and only create new terms when there were no existing terms that would do the job. We did feel that there was a need for clarity in how resources should be typed (i.e. rdf:type property) and for object properties that expressed the relationships among classes unambiguously. Please see the Rationale, DesignPrinciples and ClassesAndTypes wiki pages at the above address.
In the ontology, we sought to embody relationships among classes based on our perception of the community consensus of what the classes represent and how they are related to each other, as expressed in posts to the tdwg-content list. Thus each class is documented carefully on the wiki with hyperlinked references to specific tdwg-content posts. We also sought to clarify or resolve issues that were raised in the list discussion, most notably the relationship among Occurrences and the evidence that documents them (i.e. tokens), and the role of "individuals". See wiki pages for the Token, Occurrence, and IndividualOrganism classes.
The ontology is now in use at http://bioimages.vanderbilt.edu/, and we intend to use it more widely. We would value your opinions on the fitness of this ontology as a general solution for consistently expressing DwC concepts in RDF.
Sincerely,
Steve Baskauf and Cam Webb steve.baskauf@Vanderbilt.Edu cwebb@oeb.harvard.edu
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