- From: Drew McDermott <drew.mcdermott@yale.edu>
- Date: Tue, 1 Apr 2003 10:58:42 -0500 (EST)
- To: www-rdf-logic@w3.org
[Marty Hagenston] Maybe I read too much into the OWL Guide about how "high up" the = articulation should occur. ... Here's my example:=20 Here's my example: I have a class 9mm Automatic Pistol that has instances Beretta 92FS; Browning Highpower; SigSauer P226 and Glock 17. All specific 9mm pistols much like your specific horse types. Actually, I meant specific _horses_, but the same point is valid for subclasses as for instances (but see caveat below). I also have another class, Beretta 92 Series Pistol, in a separate ontology that has instances FS, MFS, DS, D all of which are more specific types of the Beretta 92 Series. Originally I was trying to declare the 9mm Automatic Pistol Class an equivalentClass of the Beretta 92 Series class. While both are SIMILAR, they are NOT equivalent because they do not have precisely the same instances. I don't know anything about guns, but it sounds like the Beretta 92 Series is a subclass of 9mm Automatic Pistol. Is every instance of Beretta 92 also an instance of 9mm Automatic Pistol? So my solution was to take the instance Beretta 92FS from the Automatic Pistol Class and the FS instance from the Beretta 92 Series Class and articulate at that level: <Auto_Pistol rdf:ID="Beretta 92FS"> <owl:sameIndividualAs rdf:resource="&Beretta;FS"/> (I had the proper ns defined to make this shorthand work) </Auto_Pistol> Is there a better way? Not that I know of. Is it true that if the articulation is done at the instance level, since in most cases this is the most granular level, granularity and consistency problems are avoided? That's an awfully sweeping generalization. One caveat: It's not clear why Beretta 92FS is an individual rather than a class. It seems that you will regret this choice if you ever need to talk about subclasses of the Beretta 92FS (different models, for instance), or about particular guns. However, there's no logical inconsistency in viewing the lowest-level classes as individuals, and it might even be the right thing in some contexts. -- -- Drew McDermott
Received on Tuesday, 1 April 2003 10:58:44 UTC