🤖 AI Summary
This study investigates the computational complexity of mixed Bayesian Nash equilibria in discrete first-price auctions under relevant priors. By introducing a hypergraph discrete first-price auction model as a key intermediate step and employing techniques from computational complexity theory and game-theoretic reductions, it rigorously establishes that computing such equilibria is PPAD-complete. The primary contributions are twofold. First, it delineates the theoretical upper bound on the computational hardness of finding mixed equilibria in first-price auctions. Second, it proposes a novel normal-form game model based on hypergraph auctions and proves the PPAD-completeness of computing their approximate Nash equilibria, an achievement that offers both methodological innovation and independent theoretical value.
📝 Abstract
We show that computing an approximate mixed Bayes-Nash equilibrium in a discrete first-price auction with correlated priors is PPAD-complete. The key intermediate step in our reduction is the PPAD-completeness of computing an approximate Nash equilibrium in a new normal-form game, the hypergraph discrete first-price auction, which may be of independent interest.