Assumptions in Model-based Diagnosis

Mostly, papers on problem-solving methods focus on the description of reasoning strategies and discuss their underlying assumptions as a side aspect. We take a complementary point of view and focus on these underlying assumptions as they play three important roles: first, assumptions are necessary to characterise the precise competence of a problem-solving method in terms of the tasks that can be solved by it, and in terms of the domain knowledge that is required by it. Second, assumptions are necessary to enable tractable problem solving for complex problems. Third, assumptions are necessary for appropriate interaction of the problem solver with its environment. Their introduction and refinement can be used to develop new problem-solving methods, or to adapt existing ones according to task and domain-specific circumstances of a given application. For this purpose, one requires a framework for dealing with these assumptions. This paper makes a step in this direction by summarising the assumptions that can be found in the literature on diagnosis with component-oriented device models. The main contribution of the paper is to collect these assumptions, to make their role in the reasoning process explicit, and to classify them.