Augmenting the User’s Knowledge via Comparison

The process of learning is an incremental exploration of a domain; we do not learn the concepts in a domain in an isolated manner, but instead augment our existing knowledge with new concepts. Consequently, when teaching a new concept to a student, her existing knowledge should be employed in a way which facilitates the process of learning. In describing a new concept to a hearer, it is often beneficial to compare the concept to other concepts with which the hearer is familiar. In particular, comparisons are often used in descriptions in order to reduce the cognitive load on the hearer. This paper outlines three types of comparison found in encyclopædia descriptions, and describes how a model of the user’s knowledge can be employed to produce descriptions which introduce new concepts by comparison, thus grounding descriptions in the hearer’s existing knowledge. The results are illustrated in the PEBA–II natural language generation system.