The Default Model Structure window shows a tree structure demonstrating the formation of unique Performance Classes chosen by the agency to have their own deterioration models.
Each limb-node's unique path from left to right on the tree represents a unique Performance Class.
the decision tree that determines what deterioration model to use for a particular type of road. "Type of road" means not only the type of road and how the road section is constructed, but also the condition attributes associated with that road section. Decision trees consist of parent nodes, child nodes, and the branches between them. The nodes are shown as boxes and the branches are the lines connecting the boxes. A parent node requires a user-selected decision variable and user-defined values to distinguish, and branch to, the parent's child nodes. The decision variables that may be used are selected in the Perf Class Variable column in the Setup PMS Analysis Columns window.
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