- From: Mike Bergman <mike@mkbergman.com>
- Date: Mon, 23 Feb 2009 15:24:18 -0600
- To: David Baxter <retxabd@gmail.com>
- CC: "public-lod@w3.org" <public-lod@w3.org>
David, Thanks for the guts to stroll into the lion's den. David Baxter wrote: > Hi all, > > We at Cycorp have been publishing owl:sameAs links from our OpenCyc > concepts to WordNet synsets, e.g. > > <http://sw.opencyc.org/2008/06/10/concept/en/India> owl:sameAs > <http://www.w3.org/2006/03/wn/wn20/instances/synset-India-noun-1> > > We've done so with the idea that the WordNet synset represents the same > concept as the OpenCyc term (i.e. the South Asian country in this case), > and contains further relevant information that complements what is > available in OpenCyc, e.g. > > "is a member of OPEC" (OK, this one's of dubious value, but it might be > useful if it were true) > "is a member of the British Commonwealth" > "is a part of Asia" > > However, WordNet also contains assertions about the "India" synset that > seem strange to assert about the country, e.g. > > "is an instance of NounSynset" > "contains WordSense 'Republic of India 1'" > > We'd like to know what the general feeling in the LOD community is about > these links. Is there any precedent or consensus about the best way to > link from ontologies such as OpenCyc's to WordNet? Is anyone finding > these links useful and/or harmful? > > Thanks for any input. I've rolled back to your starting message since intervening comments have unfortunately snipped out the essence of your question about owl:sameAs. Let me also again add this link from over the weekend that I think is also germane: http://i9606.blogspot.com/2009/02/semantic-dissonance-in-uniprot.html As I understand the current OWL, "an owl:sameAs statement indicates that two URI references actually refer to the same thing: the individuals have the same 'identity.'" [1]. In logical terms, I understand this to represent complete and total identity, equivalent to the '=' relationship, or something pretty doggone close to it. I also understand this property to perhaps have the strongest entailment of any OWL property. The inference from your use case and the similar issue with Ben's uniprot example are all too typical of sameAs problems once disparate datasets actually get pulled together. I appreciate the rdf:seeAlso suggestion; it is the most common fallback. But the issue with that one, which is why you went to sameAs in the first place, is that seeAlso is way too weak to convey the nature of the relationship. Sure, we could do a subPropertyOf but we could at best capture only the very weak semantics that seeAlso presently provides; we could not strengthen it. I think the real issue is that we don't have a readily available (or at least accepted) predicate. I would suggest, though, that the issue at hand is very much captured by the concept of "relative identity": http://plato.stanford.edu/entries/identity-relative/ esp. Section 3 (though there are some wonderful paradoxes throughout). What I like about 'relative identity' is that we can still infer and reason over the relationship (but *how* and weak or strong still is up for grabs). I think the considerable experience of Cycorp in such matters could be invaluable in severing this Gordian knot. Care to stroll deeper into the den? A hasRelativeIdentity B ?? Thanks, Mike [1] http://www.w3.org/TR/owl-ref/
Received on Monday, 23 February 2009 21:25:09 UTC