This article documents spillover effects using participation in an elite international football tournament as a laboratory. Using a novel dataset from top 5 European football leagues, we find that participation in highly selective UEFA Champions League (UCL) generates large performance gains to participating teams in their domestic leagues. More precisely, UCL participation improves goal difference (goals scored minus goals conceded) by approximately 0.3 goals per game and probability margin (probability of winning minus probability of losing) by approximately 10 percentage points. By investigating causal channels through which participation in the UCL might affect performance, we argue that our results suggest the importance of spillover effects in sports.

中文翻译：

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与星共舞：参加精英锦标赛会影响成绩吗？

本文以参加精英国际足球锦标赛作为实验室，记录了溢出效应。使用来自欧洲前 5 大足球联赛的新数据集，我们发现参加高度选择性的欧洲冠军联赛 (UCL) 可以为参加国内联赛的球队带来巨大的绩效提升。更准确地说，参加 UCL 可以使每场比赛的净胜球（进球数减去失球数）提高大约 0.3 个球，概率差（获胜的概率减去失败的概率）提高大约 10 个百分点。通过调查参与 UCL 可能影响表现的因果渠道，我们认为我们的结果表明溢出效应在体育运动中的重要性。