Regression Tree For (0,2,Unknown) vs. Optimal Solution

This regression tree was generated as the result of running Matlab's treefit function. The input variables were the states of the arcs and the value of the optimal solution based on the arc states. The arc states could take on one of 3 possible values:(zero, two, unknown), where zero and two represent possible arc costs for arcs that have been examined, and unknown is used to indicate that the arc cost is not known. If an arc were in the unknown state, it was also assigned an arc cost of 2.

All possible arc state combinations were generated, mapped to an arc cost vector and solved optimally. The list of arc cost states and the corresponding list of optimal solutions were regressed to generate this tree.

The nodes of the tree predict the actual solution generated by having gone down a branch.