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Next: Inferential Knowledge Up: Approaches to Knowledge Representation Previous: Simple relational knowledge

Inheritable knowledge

Relational knowledge is made up of objects consisting of

We extend the base more by allowing inference mechanisms:

Fig. 8 Property Inheritance Hierarchy

The algorithm to retrieve a value for an attribute of an instance object:

  1. Find the object in the knowledge base
  2. If there is a value for the attribute report it
  3. Otherwise look for a value of instance if none fail
  4. Otherwise go to that node and find a value for the attribute and then report it
  5. Otherwise search through using isa until a value is found for the attribute.