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arXiv · 2610.11516

A Refined Analysis for Matroid Secretary with Submodular Objectives

Dennis Joyce
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Abstract

We study the matroid secretary problem with a nonnegative monotone submodular objective. Elements arrive in uniformly random order, and every acceptance decision is immediate and irrevocable. We give an $8.699$-competitive algorithm for arbitrary matroids. The algorithm first rejects a randomly sized initial segment of the arrival sequence as a learning set and runs submodular greedy on all elements in this set. Each later element receives a fixed weight equal to the marginal value it would have when inserted into the stored greedy sequence. On these fixed weights, the algorithm runs a linear-objective matroid secretary subroutine. The algorithm uses $O(nr)$ value queries and $O(n^2)$ independence queries, where $r$ is the matroid rank.

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Dennis Joyce. 2026-10-08. A Refined Analysis for Matroid Secretary with Submodular Objectives. https://arxiv.org/abs/2610.11516

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