论文标题
图形搜索带有预测
Graph Searching with Predictions
论文作者
论文摘要
考虑一个探索未知图的代理商以寻找某些目标状态。当它在图表周围行走时,它学习了节点及其邻居。代理只知道目标状态在达到目标状态时。我们如何在仅移动较小距离时达到这个目标?这个问题似乎是没有希望的,即使在有限程度的树上,除非我们给代理商一些帮助。使用“帮助”的设置经常出现在探索大型搜索空间(例如,巨大的游戏树)中,我们假设每个节点都可以访问某些分数/质量功能,我们用来指导我们实现目标。在我们的情况下,我们假设帮助以距离预测的形式出现:每个节点$ v $提供了与目标顶点的距离的预测$ f(v)$。自然,如果这些预测是正确的,我们可以沿着最短路径实现目标。如果预测不可靠而其中一些是错误的怎么办?我们可以得到一种与预测错误有关的算法吗? 在这项工作中,我们考虑了树木上的问题,并提供确定性算法的总动作成本仅为$ O(opt +δ\ cdot err)$,其中$ opt $是从开始到目标顶点的距离,$δ$最高学位,$ err $是预测的顶点的总数。我们显示此保证是最佳的。然后,我们考虑了该问题的“计划”版本,该版本在开始时就知道了图和预测,因此代理可以使用此全局信息来设计低成本的搜索策略。对于此计划版本,我们超越了树木,并提供了一种算法,该算法在(加权)图上具有良好的性能,并具有界限的加倍尺寸。
Consider an agent exploring an unknown graph in search of some goal state. As it walks around the graph, it learns the nodes and their neighbors. The agent only knows where the goal state is when it reaches it. How do we reach this goal while moving only a small distance? This problem seems hopeless, even on trees of bounded degree, unless we give the agent some help. This setting with ''help'' often arises in exploring large search spaces (e.g., huge game trees) where we assume access to some score/quality function for each node, which we use to guide us towards the goal. In our case, we assume the help comes in the form of distance predictions: each node $v$ provides a prediction $f(v)$ of its distance to the goal vertex. Naturally if these predictions are correct, we can reach the goal along a shortest path. What if the predictions are unreliable and some of them are erroneous? Can we get an algorithm whose performance relates to the error of the predictions? In this work, we consider the problem on trees and give deterministic algorithms whose total movement cost is only $O(OPT + Δ\cdot ERR)$, where $OPT$ is the distance from the start to the goal vertex, $Δ$ the maximum degree, and the $ERR$ is the total number of vertices whose predictions are erroneous. We show this guarantee is optimal. We then consider a ''planning'' version of the problem where the graph and predictions are known at the beginning, so the agent can use this global information to devise a search strategy of low cost. For this planning version, we go beyond trees and give an algorithms which gets good performance on (weighted) graphs with bounded doubling dimension.