3 research outputs found
A paradox of tournament seeding
A mathematical model of seeding is analysed for sports tournaments where the
qualification is based on round-robin contests. The conditions of
strategyproofness are found to be quite restrictive: if each team takes its own
coefficient (a measure of its past performance), only one or all of them should
qualify from every round-robin contest. Thus the standard draw system creates
incentives for tanking in order to be assigned to a stronger pot as each team
prefers to qualify with teams having a lower coefficient. Major soccer
competitions are shown to suffer from this weakness. Strategyproofness can be
guaranteed by giving to each team the highest coefficient of all teams that are
ranked lower in its round-robin contest. The proposal is illustrated by the
2020/21 UEFA Champions League.Comment: 23 pages, 3 table