This is the archive of the goodrelations dicussion list

Note: All readers of this list who are not interested in the  
computational complexity of reasoning with GoodRelations in controlled  
settings can safely ignore this e-mail. GoodRelations will work for  
you and there is no need to unsubscribe from this list; such topics  
are a rare exception.


Dear all:

Based on very valuable input from Thorsten Liebig from derivo.de, we  
evaluated whether GoodRelations could be made fit into the OWL 2 RL  
profile, instead of just OWL 1 DL, as currently.

It turns out that this would require modifications that we cannot  
implement right now:

1. GoodRelations needs the xsd:time datatype for opening hours  
(gr:opens and gr:closes), but xsd:time is not an OWL 2 datatype. We  
could use a proprietary datatype, but that would remove the  
possibility to used xsd:time datatype validators, which have, in the  
past, spotted quite some bugs in markup.

2. The owl:unionOf constructs for the domain definition of several  
object and datatype properties cannot be replaced without introducing  
"ugly" top-level classes. For example, gr:validFrom and  
gr:validThrough can currently be attached to gr:Offering,  
gr:PriceSpecification, and gr:OpeningHoursSpecification. The  
alternative modeling would be defining a common superclass "entities  
with temporary validity", which would make the conceptual model ugly  
and would also never be used for annotating data.

In my opinion, the unionOf constructs don't really harm, since  --  
except for some validation tools -- they can be safely ignored by any  
GoodRelations-aware client. The xsd:time datatype is widely supported  
by RDF repositories and validators and is thus also safe to use.

Conclusion: For the moment, GoodRelations stays within the OWL 1 DL  
fragment.

Again, thanks to Thorsten Liebig for bringing up these issues.

Best wishes

Martin Hepp




--------------------------------------------------------
martin hepp
e-business & web science research group
universitaet der bundeswehr muenchen

e-mail:  hepp at ebusiness-unibw.org
phone:   +49-(0)89-6004-4217
fax:     +49-(0)89-6004-4620
www:     http://www.unibw.de/ebusiness/ (group)
          http://www.heppnetz.de/ (personal)
skype:   mfhepp
twitter: mfhepp

Check out GoodRelations for E-Commerce on the Web of Linked Data!
=================================================================
* Project Main Page: http://purl.org/goodrelations/
* Quickstart Guide for Developers: http://bit.ly/quickstart4gr
* Vocabulary Reference: http://purl.org/goodrelations/v1
* Developer's Wiki: http://www.ebusiness-unibw.org/wiki/GoodRelations
* Examples: http://bit.ly/cookbook4gr
* Presentations: http://bit.ly/grtalks
* Videos: http://bit.ly/grvideos