Decision making involving imperfect knowledge

The human capability of making complex decisions is one of the most fascinating facets of human intelligence, especially if vague, judgemental, default, or uncertain knowledge is involved. This paper focuses on the automation of this capability. It advocates treating rule-based decision making as a problem of evidence combination: Rules are considered to provide evidence for or against a certain decision; after the rules have been processed, the evidence associated with the individual decisions is combined and the best decision is selected. Advantages and problems of this approach are discussed and experiences the authors had in applying this approach in a Computer Bridge project are surveyed. Finally, a language construct, called a decision block, that facilitates the automation of rule-based decision making involving imperfect knowledge is introduced. The benefits of decision blocks for writing complex decision support systems are evaluated, and their integration with a rule-based forward chaining language is discussed