INFS3101/7100 Ontology and the Semantic Web

Exercises from Week 5

For discussion in tutorial week 6

Key concepts from lecture: Common to represent things as objects in classes. Objects have properties. Superclass subsumes subclass, superproperty subsumes subproperty. Properties have metaproperties rigid, essential, identity, unity which govern subsumption. Subclasses can be defined or declared.

1.           (relevant to points 7 and 8 of the assignment) Consider the rental accommodation exchange from the week 2 tutorial and the representation in the solution to the week 4 tutorial and following.

a.          Describe the classes in the ontology. Give their rigid properties, indicating whether the rigid properties are lexical or logical, and their essential properties. Show a system of subclasses for each class, inventing a plausible system if necessary.  Each subclass is either defined or declared. If it is defined, give the defining predicates. If it is declared, tell how objects are classified into the subclass and by which role. Show that the identifying and unifying relations are preserved in the subclass structure. Make plausible additions to the system if necessary.

b.           Describe a property (relationship, association) involving at least one of the classes from a. This property should have a subproperty structure. Invent a plausible structure if necessary. Show a population of property instances, including at least one instance of each subproperty.