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arXiv · 2602.18049

Optimal Competitive Ratio of Two-sided Online Bipartite Matching

Zhihao Gavin Tang
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Abstract

We establish an optimal upper bound (negative result) of $\sim 0.526$ on the competitive ratio of the fractional version of online bipartite matching with two-sided vertex arrivals, matching the lower bound (positive result) achieved by Wang and Wong (ICALP 2015), and Tang and Zhang (EC 2024).

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Zhihao Gavin Tang. 2026-02-20. Optimal Competitive Ratio of Two-sided Online Bipartite Matching. https://arxiv.org/abs/2602.18049

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