to various components of the decision model. Insight may also result from discussion of the key aspects of the reasoning that led to the formal decision model (i.e., by justifying the model). Possible actions following the appraisal stage include implementing the recommended course of action, revising the formal model and reevaluating it, or abandoning the analysis and doing something else. Justifying a decision model entails exploring and explaining the reasoning that led to the formulation of particular aspects of the decision model. Mining a decision model entails extracting information (e.g., sensitivity, value of prediction, and value of revelation) from a given decision model. Refinement Refinement is the fourth and most critical stage in using formal decision methods. The refinement stage responds to the insights obtained during the Appraisal stage. Effective refinement activities include opportunities to test possible decision model changes to see their implications and suggest better ways to modify the decision model. See also Decision engineering Decision-making models Decision Model and Notation Decision support Enterprise decision management References Holtzman, S. 1989. Intelligent Decision Systems. Addison-Wesley. Decision theory Management cybernetics