Friday, December 4th, 2020, 6pm EST
Julien Guyon (Bloomberg, NYU, Columbia)
(1) Risk of Collusion: Will Groups of Three Ruin the FIFA World Cup?
(2) “Choose Your Opponent”, a New Tournament Design
Please find a recording of the presentation below.
In 2026, the FIFA World Cup will for the first time gather 48 men’s national teams. It will consist of a group stage made of 16 groups of three, with the best two teams in each group advancing to the knockout stage. Using groups of three raises several fairness issues, including risk of match fixing and schedule imbalance. In this article we examine the risk of collusion. The two teams who play the last game in the group know exactly what results will let them advance to the knockout stage. Suspicion of match fixing occurs when a result qualifies both of them at the expense of the third team of the group, and can seriously tarnish the tournament. We quantify how often this is expected to happen and explain how to build the match schedule so as to minimize the risk of collusion. We also quantify how the risk of collusion depends on competitive balance. Moreover, we show that forbidding draws during the group stage (a rule considered by FIFA) does not eliminate the risk of match fixing, and that surprisingly when draws are forbidden the 3-2-1-0 point system does not do a better job at decreasing the risk of collusion than the 3-0 point system. Finally we describe alternate formats for a 48 team World Cup that would eliminate or strongly decrease the risk of collusion. Then, we present a new knockout format for sports tournaments, that we call “choose your opponent”, where the teams that have performed best during a preliminary group stage can choose their opponents during the subsequent knockout stage.