# The Test Ontology

Title
  The Test Ontology
URI
  http://purl.org/net/p-plan#
Version
  1.0

The following evaluation results have been generated by the RESTFul web service provided by OOPS! (OntOlogy Pitfall Scanner!).

It is obvious that not all the pitfalls are equally important; their impact in the ontology will depend on multiple factors. For this reason, each pitfall has an importance level attached indicating how important it is. We have identified three levels:

Critical
  It is crucial to correct the pitfall. Otherwise, it could affect the ontology consistency, reasoning, applicability, etc.
Important
  Though not critical for ontology function, it is important to correct this type of pitfall.
Minor
  It is not really a problem, but by correcting it we will make the ontology nicer.

## Evaluation results

#### P38. No OWL ontology declaration ontology *Important

The owl:Ontology tag aims at gathering metadata about a given ontology as version information, creation date, etc. It is also used to declare the inclusion of other ontologies. Not declaring this tag is consider as a bad practice for owl ontologies as it is a symptom of not providing useful metadata as proposed in LDV2. An example of this pitfall (at 29th June, 2012) could be found at the "Creative Commons Rights Expression Language (cc)" ontology, which URI is http://creativecommons.org/ns, that does not have any owl:Ontology declaration in its RDF file even though there are other OWL elements used as, for example, owl:equivalentProperty.

*This pitfall applies to the ontology in general instead of specific elements

#### P39. Ambiguous namespace ontology *Critical

In the case of not having defined the ontology URI nor the xml:base namespace, the ontology namespace is matched to the file location. This situation is not desirable as the location of a file might change while the ontology should remain stable as proposed in LDV1. An example of this pitfall (at 29th June, 2012) could be found at the "Basic Access Control ontology (acl)" with URI http://www.w3.org/ns/auth/acl has no owl:Ontology tag nor xml:base def-inition.

*This pitfall applies to the ontology in general instead of specific elements

References:

- [1] Gómez-Pórez, A. Ontology Evaluation. Handbook on Ontologies. S. Staab and R. Studer Editors. Springer. International Handbooks on Information Systems. Pp: 251-274. 2004.
- [2] Noy, N.F., McGuinness. D. L. Ontology development 101: A guide to creating your first ontology. Technical Report SMI-2001-0880, Standford Medical Informatics. 2001.
- [3] Rector, A., Drummond, N., Horridge, M., Rogers, J., Knublauch, H., Stevens, R.,; Wang, H., Wroe, C. ''Owl pizzas: Practical experience of teaching owl-dl: Common errors and common patterns''. In Proc. of EKAW 2004, pp: 63-81. Springer. 2004.
- [4] Hogan, A., Harth, A., Passant, A., Decker, S., Polleres, A. Weaving the Pedantic Web. Linked Data on the Web Workshop LDOW2010 at WWW2010 (2010).
- [5] Archer, P., Goedertier, S., and Loutas, N. D7.1.3 - Study on persistent URIs, with identification of best practices and recommendations on the topic for the MSs and the EC. Deliverable. December 17, 2012.
- [6] Heath, T., Bizer, C.: Linked data: Evolving the Web into a global data space (1st edition). Morgan & Claypool (2011).