It is known that A* is optimal with respect to the expanded nodes (Dechter and Pearl 1985) (D&P). The exact meaning of this optimality varies depending on the class of algorithms and instances over which A* is claimed to be optimal. A* does not provide any optimality guarantees with respect to the generated nodes. However, such guarantees may be critical for optimally solving instances of domains with a large branching factor. In this paper, we introduce two new variants of the recently introduced Enhanced Partial Expansion A* algorithm (EPEA*) (Felner et al. 2012). We leverage the results of D&P to show that these variants possess optimality with respect to the generated nodes in much the same sense as A* possesses optimality with respect to the expanded nodes. The results in this paper are theoretical. A study of the practical performance of the new variants is beyond the scope of this paper.
|Number of pages||9|
|State||Published - 1 Dec 2013|
|Event||6th Annual Symposium on Combinatorial Search, SoCS 2013 - Leavenworth, WA, United States|
Duration: 11 Jul 2013 → 13 Jul 2013
|Conference||6th Annual Symposium on Combinatorial Search, SoCS 2013|
|Period||11/07/13 → 13/07/13|