Moving-Target Searchの完全性 : 評価関数が一貫性を欠く場合

抄録

We discuss the effect of inconsistent heuristics on the completeness property of the Moving-Target Search (MTS), a real-time search algorithm for changing goals. Although MTS can be considered as a natural extension of the stationary-goal real-time search algorithm LRTA, it is augmented with an extra operation to force the consistency of heuristic estimates. We argue that this extra operation, which ensures the updating of the heuristic estimates is carried out only when it increases the current value, can be safely eliminated from MTS as well. We also show that the completeness is preserved even if the heuristic function is inadmissible (and hence inconsistent). These results elucidate the nature of the MTS algorithm, and broaden the class of heuristic functions that can be used with MTS without violating the completeness.