Several sports tournaments establish restrictions on the draw of the group stage. In this case, the usual mechanism to assign the teams into groups is unevenly distributed: the valid allocations are not equally likely. We show by two illustrative examples how the lack of randomisation in the size of the groups and the inflexible treatment of a sophisticated draw constraint can increase unfairness. Based on these ideas, the draw of the European Qualifiers for the 2022 FIFA World Cup could have been closer to uniform distribution without any negative effects. Our recommendation for a careful relabelling of the pots from which the teams are drawn has a decent chance to be implemented in practice.
翻译:几个运动比赛设定了分组阶段的限制。在这种情况下,分配团队到组中的通常机制不均匀分布:有效的分配并不是同样可能的。我们通过两个说明性例子展示了当组大小的随机化缺失以及复杂的抽签限制的不灵活处理导致不公平性增加。基于这些想法,欧洲区2022年世界杯预选赛的抽签可能更接近均匀分布,而不会产生任何负面影响。我们建议对团队抽签来源进行重新标记,以在实践中得以实施。