重新考虑双向启发式搜索
Bidirectional Heuristic Search Reconsidered
摘要：
自25年前首次发表以来，对双向启发式搜索的评估一直是不正确的。长期以来，这种搜索策略并没有达到预期的效果，而且人们对它背后的原因存在着很大的误解，虽然人们仍然普遍认为双向启发式搜索存在搜索边界相互穿越的问题，但我们证明了这种猜想是错误的。基于这一发现，我们提出了一个新的通用方法，双向启发式搜索和一个新的方法来动态地提高启发式值，是可行的双向搜索。这些方法与传统的和最近提出的方法相结合，以促进更好的全面理解。我们的新方法的实验结果表明，双向启发式搜索可以非常有效地进行，也与有限的内存。这些结果表明，双向启发式搜索似乎是更好地解决某些困难的问题比相应的单向搜索。这为长期被忽视的搜索策略的有用性提供了一些证据。总之，我们表明，双向启发式搜索是可行的，因此建议重新考虑。
英文摘要：
The assessment of bidirectional heuristic search has been incorrect since it was first published more than a quarter of a century ago. For quite a long time, this search strategy did not achieve the expected results, and there was a major misunderstanding about the reasons behind it. Although there is still wide-spread belief that bidirectional heuristic search is afflicted by the problem of search frontiers passing each other, we demonstrate that this conjecture is wrong. Based on this finding, we present both a new generic approach to bidirectional heuristic search and a new approach to dynamically improving heuristic values that is feasible in bidirectional search only. These approaches are put into perspective with both the traditional and more recently proposed approaches in order to facilitate a better overall understanding. Empirical results of experiments with our new approaches show that bidirectional heuristic search can be performed very efficiently and also with limited memory. These results suggest that bidirectional heuristic search appears to be better for solving certain difficult problems than corresponding unidirectional search. This provides some evidence for the usefulness of a search strategy that was long neglected. In summary, we show that bidirectional heuristic search is viable and consequently propose that it be reconsidered.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
