- From: Johnson, Matthew C. (LNG-HBE) <Matthew.C.Johnson@lexisnexis.com>
- Date: Wed, 21 May 2008 17:10:29 -0400
- To: <semantic-web@w3.org>
- Message-ID: <0FE5E87C5F0AE84B8C667FDC5224F6DA0229EFA2@LNGDAYEXCP01VC.legal.regn.net>
Hi, I'm slowing soaking in what OWL can and cannot do and after reading the "Lessons For Ontology Writers" post [1] by Ian Davis, I thought I'd go ahead and ask this capabilities question here. In OWL, can you directly define a property that says that something does not occur. My current use-case is in determining hyper-linking relationships between various publications. The following: mysch:Pub a rdfs:Class . mysch:linksTo a rdf:Property . mypubs:p1 a mysch:Pub . mypubs:p2 a mysch:Pub . mypubs:p3 a mysch:Pub . mypubs:p1 mysch:linksTo mypubs:2 . mypubs:p3 mysch:linksTo mypubs:2 . Lets me say that pub 1 links to pub 2 and that pub 3 links to pub 2. However, if I understand the open-world assumption, I cannot assume that pub 2 does not link to pub 3. I would need to define something like: mysch:notLinksTo a rdf:Property . to explicitly state this fact that pub 2 does not link to pub 3. My question is whether it is possible in OWL to define a property whose range of acceptable instances is the list of instances that do not exist as an object in a mysch:linksTo statement (for a given publication)? While statically stating that pub 2 does not link to pub 3 is technically possible for me, it seems unfortunate. This is because when a new pub comes along (e.g. mysch:p4), I then have to update all the statements I've already made. This is the part that Ian Davis agreed would cause an explosion of triples. I would really like to only state the things that I can programmatically find by parsing the raw syntax of a publication (e.g. I can find a <a href...> element which provides the mysch:linksTo assertion) and would rather the system infer that the lack of a <mysch:linksTo> relationship really means a <mysch:notLinksTo>. Perhaps the answer is really through SPARQL. I hope I've made my question(s) clear. Please let me know if I haven't. Thanks for the advice! Matt [1] http://blogs.talis.com/nodalities/2008/05/lessons-for-ontology-writers.p hp
Received on Wednesday, 21 May 2008 21:11:18 UTC