Re: OWL 2 Profiles and Horn-SHIQ

Dear Christian,

When discussing fragments (now called profiles) the OWL Working Group  
decided that having too many different profiles might be confusing to  
potential users of OWL, and that  we should therefore try to limit  
the number of profiles and only describe those for which (a) there is  
a clear user requirement; (b) there is sufficient implementer  
support; (c) there are significant distinguishing characteristics  
(e.g., computational or implementational) w.r.t. other profiles. The  
WG is not aware of strong user requirements or implementer support  
for Horn-SHIQ, and it's characteristics seem to be quite similar to  
those of the OWL-R profile.

If you would like the WG to reconsider, could you provide additional  
information about Horn-SHIQ that addresses the above points.

Regards,
Ian Horrocks
Co-Chair, W3C OWL Working Group


On 30 May 2008, at 18:14, Christian Halaschek-Wiener wrote:

> Greetings,
>
> I’m with an investment firm currently using OWL for a variety of  
> purposes internally within our company (some of you know me  
> previously from my time spent in Jim’s Mindswap research group at  
> UMD). We’re very interested in the work the group is doing on  
> defining tractable subsets/profiles of OWL 2, as performance  
> guarantees are very important for our usage. I recently happened to  
> notice that one of the original member submissions related to  
> tractable fragments [1] included Horn-SHIQ. While being  
> syntactically restricted and having intractable taxonomic  
> complexity, this fragment is interesting to us because it provides  
> modeling constructs not possible with the current profiles defined  
> in [2] (e.g., simultaneous usage of existential quantification,  
> inverse & transitive roles, etc.) and still has tractable data  
> complexity. I was wondering if there were specific reasons why this  
> profile is not currently included in the latest working draft?  
> Thanks for any insight or clarity the group can provide.
>
> Cheers,
> Chris
>
> [1] http://www.w3.org/Submission/owl11-tractable/
> [2] http://www.w3.org/TR/owl2-profiles/
>
> --
> Christian Halaschek-Wiener, Ph.D.
> Chief Technology Officer
> Clados Management LLC