Explaining Exceptional Cases Focusing on Solving the Missing Data Problem

In medical practice and in knowledge-based systems too, it is necessary to consider exceptions and to deal with them appropriately. In this paper, a system is presented, which helps to explain cases that do not fit to a theoretical hypothesis. It is proposed to combine Case-Based Reasoning with a statistical model, where Case-Based Reasoning is used to explain the exceptional cases. Additionally, a method to partly solve the missing data problem was developed. This method combines general restoration techniques with domain dependent formulas provided by an expert. For the latter technique, Case-Based Reasoning is applied again.