- From: Dave Reynolds <dave.e.reynolds@gmail.com>
- Date: Fri, 09 Nov 2012 12:09:31 +0000
- To: public-gld-wg@w3.org
Hi João Paulo, On 09/11/12 10:38, João Paulo Almeida wrote: > Hi Dave, > >>> org:Post is a subclass of org:Organization >>> >>> org:Organization is a subclass of foaf:Person >>> >>> Thus, org:Post is a subclass of foaf:Agent. >> >> Correct. >> >>> This means that the union in the domain and range would be unnecessary >>> (as >>> foaf:Agent would cover all the possibilities). >> >> Yes but foaf:Agent is a more general statement than the current union. >> That generalization wouldn't do any harm but the current approach makes >> the fact that an organization can hold a post more explicit, which is >> desirable. > > I was talking about "reportTo", whose domain and range is owl:unionOf > (foaf:Agent and org:Post). This seems unnecessary to me, if you assume > that org:Post is a subclass of foaf:Agent. [which I argue against, but I > will have to elaborate on this some other time.] Ah, sorry for misunderstanding. You are correct that the union is redundant, though not wrong. We could modify the domain/range statements to be foaf:Agent and explain that you can reportTo an org:Post in the prose. I'll log that possibility as an issue. >>> And >>> what about foaf:birthday (a property of foaf:Agent)Š This would also be >>> an >>> unusual >>> property of an org:Post. >> >> True but just because a property exists doesn't mean it can be applied >> blindly to any particular instance. There is no cardinality constraint >> that makes foaf:birthday a required property. Equally I wouldn't use >> foaf:birthday on an org:Organization even though that is not explicitly >> banned. > > This is some kind of highly informal constraint on the ontology that in my > opinion should be avoided. If you say that org:Post and org:Organization > are subclasses of foaf:Agent than all statements about foaf:Agent ought to > be meaningful for org:Organization and org:Post, which is not the case > here. First, note that ORG does not import foaf, it merely refers to it. Second, that is not a constraint. Like all properties in foaf foaf:birthday is optional, to be used where appropriate. For a government department I personally wouldn't use it. However, there are times when it could be appropriate. For example, I work for a small company which started trading three years ago today, we did indeed say "now we are three years old" as if it were a birthday. So I would be happy using foaf:birthday on an org:Organization resource that represented us. >>>>> The semantics of "reportTo" between foaf:Agents >>>>> is that the agents have some kind of reporting relationship in the >>>>> scope of some (undetermined) organization. In this case, it would be >>>>> unreasonable to expect that "reportsTo" is acyclic between >>>>> foaf:Agents... >>>>> In contrast, the semantics of "reportsTo" between foaf:Posts is that >>>>> there exists some kind of reporting relation in the scope of a >>>>> specific organization. In this case, "reportsTo" may as well be >>>>> acyclic, as suggested (?) in the current document in a usage note for >>>>> "headOf". >>>> >>>> That's a different issue. It is possible that the comment on acyclic >>>> relationships is too strong. >>> >>> Ok, so how should this be processed into the current draft? (Sorry for >>> the >>> question, I am new to this!) do we track these issues somehow? >> >> If the working group agrees that that is an issue that should be >> addressed then it gets logged on the issue tracker [2]. >> >> That would be a small editorial change and would not affect Last Call so >> I'd be happy to see that logged as an issue. I've also logged that as an issue. Dave
Received on Friday, 9 November 2012 12:10:05 UTC