Formalizing Dependency Directed Backtracking and Explanation Based Learning in Refinement Search

The ideas of dependency directed backtracking (DDB) and explanation based learning (EBL) have developed independently in constraint satisfaction, planning and problem solving communities. In this paper, I formalize and unify these ideas under the task-independent framework of refinement search, which can model the search strategies used in both planning and constraint satisfaction. I show that both DDB and EBL depend upon the common theory of explaining searchfailures,and regressing them to higher levels of the search tree. The relevant issues of importance include (a) how the failures are explained and (b) how many failure explanations are remembered. This task-independentunderstandingof DDB and EBL helps support cross-fertilization of ideas among Constraint Satisfaction, Planning and Explanation-Based Learning communities.

• Type: Conference
• Year: 1996
• Where: AAAI
• Authors: Subbarao Kambhampati
• Keywords: AAAI 1996, Constraint Satisfaction, Explanation Based Learning, Intelligent Agents, Problem Solving Communities