- From: Steve Harris <swh@ecs.soton.ac.uk>
- Date: Wed, 9 Jul 2008 13:38:44 +0100
- To: public-lod@w3.org, semantic-web at W3C <semantic-web@w3c.org>
On 9 Jul 2008, at 13:04, Bijan Parsia wrote: > > On 9 Jul 2008, at 12:53, Yves Raimond wrote: > >>> If the best data / tools you have suggest that two docs/datasets are >>> describing the selfsame entity, using owl:sameAs seems fine, even >>> if you >>> have a secret hunch you're only perhaps 95% confident of the data >>> quality or >>> tool reliability. If the best information you have instead is >>> telling you >>> "these two documents seem to be talking about more or less the >>> same notion", >>> then owl:sameAs probably isn't for you: it doesn't communicate >>> what you >>> know. Which of these situations you're in might be something of a >>> judgement >>> call, but it should be a judgement call grounded in clarity about >>> what a use >>> of owl:sameAs is claiming. >> >> Just jumping on that part. My particular use-case is that I have an >> algorithm to automatically derive owl:sameAs between two datasets >> [1]. >> This algorithm gives a really low-rate of false-positives after >> evaluation. However, whenever this tool publish an owl:sameAs >> statement, it has a "confidence" associated with it. Is there any >> "standard" way to publish this confidence, as well as the sameAs >> statement? > > No. OWL2 allows for axiom annotations, but these tend to look fairly > ugly in RDF (due to reification). > > If you wanted to support some inference with those, you may want to > try Pronto: > http://pellet.owldl.com/pronto > > Pavel and I are looking for test data. > > We also used axiom annotations to associate probabilities with > assertions, see: > http://www.w3.org/2007/OWL/wiki/Annotation_System > esp. > http://www.w3.org/2007/OWL/wiki/Annotation_System#Probabilistic_extension That looks interesting, but I can't read OWL(2) syntax, so can't imagine what the interpretation in triples would look like. Yves' problem could be solved with "hand-reification" (I'm sure there's a proper term for it), a la: <http://example.org/a> :similarToConfidence [ :similarTo <http://example.org/b> ; :confidence 0.4 ; ] . That doesn't have any strict interpretation of course, but it is at least more convenient to work with at an RDF level. > You might also look at my reificaiton table: > http://www.w3.org/2007/OWL/wiki/Reification_Alternatives I like the data URI one, though it has some issues, possibly not as many as the other schemes. Named Graphs are somewhat blessed by the SPARQL GRAPH operator - it's doesn't give all of the named graphs idea but gives enough. Probably not useful for annotations on small units of RDF though. - Steve
Received on Wednesday, 9 July 2008 12:39:43 UTC