论文标题

最小跨越树的学习调查策略不确定性

Learning-Augmented Query Policies for Minimum Spanning Tree with Uncertainty

论文作者

Erlebach, Thomas, de Lima, Murilo Santos, Megow, Nicole, Schlöter, Jens

论文摘要

我们研究了如何在模型中使用(可能是错误的)预测,以在不确定性下进行计算,其中算法可以查询未知数据。我们的目的是最大程度地减少解决最小跨越树问题所需的查询数量,这是一个基本的组合优化问题,对可探索的不确定性研究领域也是至关重要的。对于所有积分$γ\ ge 2 $,我们提出算法是$γ$ -Robust和$(1+\ frac {1}γ)$ - 一致,这意味着它们最多可以使用$γopt$ queries,如果预测的预测最多是错误的,最多是$ $ \ frac $ \ frac \ frac $ corporties options opties n octions optivies optivion n octions op cortivies op corportive,corpor n ock oct ock ock ock ock ock ock ock ock ock ock ock {给定实例的查询。此外,我们表明这种权衡是最好的。此外,我们认为,适当定义的HOP距离是预测误差和设计算法的有用度量,其性能可以确保随着跃距距离平稳地降解。我们还表明,这些预测在我们的模型中是可pac-carnn的。我们的结果表明,不受信任的预测可以规避〜$ 2 $的已知下限,而不会降解最差的比率。为了获得我们的结果,我们为最小生成树问题提供了新的结构见解,这些洞察力在基于查询的算法的背景下可能很有用。特别是,我们通过提出新颖的全球见证人设定结构和全新的适应性使用这些结构来概括证人集的概念 - 降低最佳限制的关键。

We study how to utilize (possibly erroneous) predictions in a model for computing under uncertainty in which an algorithm can query unknown data. Our aim is to minimize the number of queries needed to solve the minimum spanning tree problem, a fundamental combinatorial optimization problem that has been central also to the research area of explorable uncertainty. For all integral $γ\ge 2$, we present algorithms that are $γ$-robust and $(1+\frac{1}γ)$-consistent, meaning that they use at most $γOPT$ queries if the predictions are arbitrarily wrong and at most $(1+\frac{1}γ)OPT$ queries if the predictions are correct, where $OPT$ is the optimal number of queries for the given instance. Moreover, we show that this trade-off is best possible. Furthermore, we argue that a suitably defined hop distance is a useful measure for the amount of prediction error and design algorithms with performance guarantees that degrade smoothly with the hop distance. We also show that the predictions are PAC-learnable in our model. Our results demonstrate that untrusted predictions can circumvent the known lower bound of~$2$, without any degradation of the worst-case ratio. To obtain our results, we provide new structural insights for the minimum spanning tree problem that might be useful in the context of query-based algorithms regardless of predictions. In particular, we generalize the concept of witness sets -- the key to lower-bounding the optimum -- by proposing novel global witness set structures and completely new ways of adaptively using those.

扫码加入交流群

加入微信交流群

微信交流群二维码

扫码加入学术交流群,获取更多资源