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arXiv · 1902.04635

Optimal Budget-Feasible Mechanisms for Additive Valuations

Nick Gravin·Yaonan Jin·Pinyan Lu·Chenhao Zhang
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Abstract

In this paper, we show a tight approximation guarantee for budget-feasible mechanisms with an additive buyer. We propose a new simple randomized mechanism with approximation ratio of $2$, improving the previous best known result of $3$. Our bound is tight with respect to either the optimal offline benchmark, or its fractional relaxation. We also present a simple deterministic mechanism with the tight approximation guarantee of $3$ against the fractional optimum, improving the best known result of $(2+ \sqrt{2})$ for the weaker integral benchmark.

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Nick Gravin, Yaonan Jin, Pinyan Lu, Chenhao Zhang. 2019-02-12. Optimal Budget-Feasible Mechanisms for Additive Valuations. https://arxiv.org/abs/1902.04635

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