FAGAN@SUMEX-AIM.ARPA (Larry Fagan) (05/17/86)
A Decision-Theoretic Approach to Explaining Heuristic Planning Curtis P. Langlotz PhD Oral Exam Medical Information Sciences Stanford University Thursday, May 22, 1:15 PM Medical Center M-112 Many important planning problems are characterized by uncertainty about the current situation and by uncertainty about the consequences of future action. These problems also inevitably involve tradeoffs between the costs and benefits associated with possible actions. Decision theory is an extensively studied methodology for reasoning under these conditions, but has not been explicitly and satisfactorily integrated with artificial intelligence approaches to planning. Likewise, many perceived practical limitations of decision theory, such as problem solving results that are difficult to explain and computational needs that are difficult to satisfy, can be overcome through the use of artificial intelligence techniques. This thesis explores the combination of decision-theoretic and artificial intelligence approaches to planning, and shows that this combination allows better explanation of planning decisions than either one alone. In addition, the explicit representation of probabilities and utilities allows flexibility in the construction of a planning system. This means that assumptions made by such systems, which may be critical for their performance, are more easily modified than in a system that does not explicitly represent uncertainties and tradeoffs.