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arXiv · 2211.12431

Finding Almost Tight Witness Trees

Dylan Hyatt-Denesik·Afrouz Jabal Ameli·Laura Sanità
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Abstract

This paper addresses a graph optimization problem, called the Witness Tree problem, which seeks a spanning tree of a graph minimizing a certain non-linear objective function. This problem is of interest because it plays a crucial role in the analysis of the best approximation algorithms for two fundamental network design problems: Steiner Tree and Node-Tree Augmentation. We will show how a wiser choice of witness trees leads to an improved approximation for Node-Tree Augmentation, and for Steiner Tree in special classes of graphs.

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Dylan Hyatt-Denesik, Afrouz Jabal Ameli, Laura Sanità. 2022-11-22. Finding Almost Tight Witness Trees. https://arxiv.org/abs/2211.12431

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