On monotone approximate and exact equilibria of an asymmetric first-price auction with affiliated private information.

This paper develops a new approach to investigating equilibrium existence in first-price auctions with many asymmetric bidders whose types are affiliated and valuations are interdependent and not necessarily strictly increasing in own type. We begin with studying a number of continuity-related properties of the model, which are used, in conjunction with tieless single crossing and H-convexity, to establish the existence of monotone approximate interim equilibria. Then we provide two sets of sufficient conditions for the game to have a sequence of monotone approximate equilibria whose limit points are pure-strategy Bayesian-Nash equilibria.