Limits on the Social Welfare of Maximal-In-Range Auction Mechanisms

Many commonly-used auction mechanisms are "maximal-in-range". We show that any maximalin-range mechanism for n bidders and m items cannot both approximate the social welfare with a ratio better than min(n, m ) for any constant < 1/2 and run in polynomial time, unless NP P/poly. This significantly improves upon a previous bound on the achievable social welfare of polynomial time maximal-in-range mechanisms of 2n/(n + 1) for constant n. Our bound is tight, as a min(n, 2m1/2 ) approximation of the social welfare is achievable.

• Type: Conference
• Year: 2010
• Where: SODA
• Authors: Dave Buchfuhrer, Chris Umans
• Keywords: Achievable Social Welfare, Commonly-used Auction Mechanisms, Discrete Algorithms, Polynomial Time, SODA 2010