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arXiv · 0901.1427

An Online Multi-unit Auction with Improved Competitive Ratio

Sourav Chakraborty·Nikhil Devanur
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Abstract

We improve the best known competitive ratio (from 1/4 to 1/2), for the online multi-unit allocation problem, where the objective is to maximize the single-price revenue. Moreover, the competitive ratio of our algorithm tends to 1, as the bid-profile tends to ``smoothen''. This algorithm is used as a subroutine in designing truthful auctions for the same setting: the allocation has to be done online, while the payments can be decided at the end of the day. Earlier, a reduction from the auction design problem to the allocation problem was known only for the unit-demand case. We give a reduction for the general case when the bidders have decreasing marginal utilities. The problem is inspired by sponsored search auctions.

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Sourav Chakraborty, Nikhil Devanur. 2009-01-11. An Online Multi-unit Auction with Improved Competitive Ratio. https://arxiv.org/abs/0901.1427

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