Who chokes on a penalty kick? Social environment and individual performance during Covid-19 times
利用新冠疫情导致球场空场的自然实验，分析法德意西英顶级足球联赛2019/20赛季点球数据，发现主队点球命中率下降而客队提高，且赛前上座率越高影响越明显，说明观众规模对技能任务表现有重要作用。
We use hand-collected data on penalty kicks in the top-level football competitions across France, Germany, Italy, Spain, and the United Kingdom over the 2019/2020 season to analyse how social environment affects the performance of individuals. We exploit the Covid-19 outbreak to induce a plausible source of variation in the supporters' attendance. We find that for home teams the probability of missing a penalty increases when matches are forced to be played behind closed doors, while visiting teams are less likely to choke on a penalty kick, with these effects being more pronounced when the level of attendance (measured before the pandemic) was high. Taken together, these findings indicate that not only a supportive audience, but also the size of the support plays a key role for success of skill tasks.