PrecisionTree: Calculation Algorithm for Decision Trees

End node values are path sums; probabilities are product of branch probabilities; decision nodes use TRUE branch; chance nodes use weighted averages.

Title

Answer

Applies to: PrecisionTree 5.x and Up

The value of an end node is the sum of the values along the path from the root.

The probability (percentage) of an end node is the product of the branch probabilities along that path, counting TRUE as 1 and FALSE as 0.
Working from right to left, the value of a chance node is the weighted average of its child nodes, and the value of a decision node is the value of the node on its TRUE branch.

For more detail, see Appendix A in the PrecisionTree user manual (Help » Documentation » Manual).

Attachments:
PrecisionTree_AppendixA

URL Name

calculation-algorithm-for-decision-trees

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