Database Reference
In-Depth Information
the ontology will be put; for application ontologies, these are typically the use cases
of the application (e.g., monitoring the health of a habitat).
Competency questions are used to test whether the ontology meets its scope and
purpose and effectively provide test cases for the ontology. There are two forms of
question; the first tests for the completeness of the ontology; the second provides
the basis to generate tests of the correctness of specific aspects of the ontology that
can be translated into SPARQL or DL (Description Logic) queries. For the Spatial
Relations ontology, a competency question to test completeness could be: Does the
ontology contain all the RCC8 relationships and only these relations?
A test for correctness could be a test of the transitive nature of “contains” by
specifying the expected behavior of the property. Specifically, the test could com-
prise the following:
Given:
A contains B.
B contains C.
D disjoint A.
D disjoint B.
D Disjoint C.
Then the test:
A contains ?x.
Should return B and C but not D.
They enable testing of the connectedness of the ontology. Ideally, the competency
questions should be defined as early in the process as possible. It may be easier for
the domain expert to couch the competency questions in terms of the application
requirements; “Find all Parishes that contain Hospitals,” for example.
10.3.3 l
lexicon
The lexicon is constructed to build a list of the terms that need to be described within
the ontology and that form the vocabulary. Typically, this is done by analyzing the
content of documents related to the domain or application of interest and interview-
ing experts within the field. If there is doubt whether a term should be included in
the lexicon, it is useful to hold the term up against the light of the scope and purpose.
10.3.4 g
lossary
The glossary stage takes each term from the lexicon and develops an informal expla-
nation expressed in natural language. This stage will also attempt to discriminate
between core and secondary concepts. Core concepts are central to the scope of
the ontology; secondary concepts are not strictly part of the domain or application
