Choosing an ontology: OAC

Part of Pelagios' first Workpackage is to decide on a Common Ontology for Place References (COPR). In doing so we are not attempting to reinvent the wheel - far from it. Good Linked Open Data practice is to reduce, reuse and recycle. To that end we have been investigating a variety of options and are now basing our approach on the Open Annotation Collaboration ontology.

The OAC is also a work in progress but, as luck would have it, they are holding their workshop in Chicago on exactly the same dates as ours (we now have a great line-up, btw, so register soon as places are filling up). Their fundamental principles seem to be exactly what we are looking for though: the ability to connect a target web document with some information about it (in our case, an ancient place).

The basics should look something like this:

ex:ann1 oac:Annotation
       oac:hasBody "http://pleiades.stoa.org/places/423025"
       oac:hasTarget <some resource identifying the text + fragment>


But a number of interesting issues remain - should we use Blank Nodes for the annotations themselves (especially in RDFa)? If not, where do we store them? Should we subclass the OAC ontology to specify that it is a geographic annotation? If so should it be the oac:Annotation or oac:hasBody that we subclass, and where should that ontology be hosted? We are fortunate to have the assistance of Bernhard Haslhofer and Robert Sanderson in this discussion, who are both involved with OAC and look forward to them reporting back from OAC's workshop. In the meantime Mathieu D'Aquin is putting together our own SPARQL demonstrator to see how useful this approach may be in practice.


If you have any thoughts on this do let us know and you can follow the discussion itself over on our Google Group.