
When Collusion Cuts Prices: The Counterintuitive Economics of Algorithmic Bidding
Most warnings about algorithmic collusion tell the same story: sellers using AI to set prices end up coordinating—without explicit communication—to keep prices higher than competition would allow. This is what regulators fear: supra-competitive prices, reduced consumer welfare, and harder-to-detect anti-competitive behavior. A new study, however, flips the narrative on its head. By analyzing multi-dimensional decision-making—where reinforcement learning (RL) agents set both prices and advertising bids on a platform like Amazon—the authors uncover a surprising outcome: in markets with high consumer search costs, algorithmic “collusion” can lower prices below competitive benchmarks. ...