Improved Truthful Mechanisms for Combinatorial Auctions with Submodular Bidders

A longstanding open problem in algorithmic mechanism design is to truthful mechanisms that are computationally efficient and (approximately) maximize welfare combinatorial auctions with submodular bidders. The first such was obtained by Dobzinski, Nisan, Schapira [Proceedings of the 37th Annual ACM Symposium on Theory Computing, Baltimore, MD, ACM, New York, 2005, pp. 610–618] who gave an -approximation, where number items. This has been studied extensively since, culminating -approximation Dobzinski 48th SIGACT STOC 2016, Cambridge, MA, 940–948]. We present a computationally-efficient approximation ratio improves upon state-of-the-art exponential factor. In particular, our achieves expectation, uses only demand queries, universal truthfulness guarantee. settles question whether best this setting negative.