Types of Explanations.

Abstract : Many people in AI want to use explanations in their work, but nobody (including us) knows enough about them. Although explanation has been the foundation of much AI research, little attention has been paid to two fundamental questions one would like to be able to answer about explanation: What are the kinds of things that need to be explained and what are the types of explanations? This report is an attempt to map out that territory by developing a categorization scheme that covers a substantial variety of anomalies and explanations. We have collected a large group of real-world explanations and studied their similarities in order to understand what categories they fall into. In this paper the anomalies which need to be explained are divided into three broad classes: intentional, social and material anomalies. We discuss the three classes, and present the different kinds of explanations that can apply to each. Keywords: Explanation, Categorization, Anomaly types, Story understanding.