Collusion-Resilient Truly Combinatorial Auctions, Player-Knowledge Benchmarks, and Equilibrium-Less Solution Concepts

We put forward a new mechanism achieving a high benchmark for (both revenue and) the sum of revenue and efficiency in truly combinatorial auctions. Notably, our mechanism guarantees its performance • in a very adversarial collusion model; • for any profile of strategies surviving the iterated elimination of dominated strategies; and • by leveraging the knowledge that the players have about each other (in a non-Bayesian setting). Our mechanism also is computationally efficient, and preserves the players’ privacy to an unusual extent.