suppliers. We show that an importer country sometimes helps producer countries organize and enforce collusion to advance ….g., the Soviet Union). Moreover, using this practice, a powerful importer country can immediately share the cost of collusion … with other importers (including allies). Thus, a powerful importer country may see collusion as a superior strategy to …

basis of suspicious bidding patterns and cartels can adapt to the statistical screens used by regulators. We emphasize the …, regardless of the underlying economic environment. Our main result establishes that screening for collusion with safe tests is a …

observing online behavior and conducting experiments is difficult without direct access to the user base and software of …