The DTREE Procedure

The VPI statement causes PROC DTREE to compute the value of perfect information. The value of perfect information is the benefit of resolving an uncertain stage before making a decision. This value is the upper limit on the improvement that can be expected for any information gathering effort. Only the name of a chance stage can be used to calculate the value of perfect information. The procedure evaluates the decision tree, if it has not already done so, before computing this value.