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arXiv · 1906.06217

Matroidal Approximations of Independence Systems

Sven de Vries·Rakesh V. Vohra
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Abstract

Milgrom (2017) has proposed a heuristic for determining a maximum weight basis of an independence system ${\mathcal I}$ given that we want an approximation guarantee only for sets in a prescribed ${\mathcal O}\subseteq {\mathcal I}$. This ${\mathcal O}$ reflects prior knowledge of the designer about the location of the optimal basis. The heuristic is based on finding an `inner matroid', one contained in the independence system. We show that even in the case ${\mathcal O}={\mathcal I}$ of zero additional knowledge the worst-case performance of this new heuristic can be better than that of the classical greedy algorithm.

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Sven de Vries, Rakesh V. Vohra. 2019-06-14. Matroidal Approximations of Independence Systems. https://arxiv.org/abs/1906.06217

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