This research examines the impact of defensive coordinators and head coaches on team defensive performance in the National Football League (NFL). We find that elite and very poor defensive coordinators and head coaches can have meaningful impacts on their teams’ defensive performances. A team’s defensive performance is shown to improve with increased defensive coordinator tenure. Similarly, defensive coordinators and head coaches who were NFL players contribute to improved defensive performance compared to coaches without experience as NFL players. In addition, a 3-4 defensive alignment is found to be associated with improved defensive performance compared to a 4-3 defensive alignment.

中文翻译：

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防守协调员和主教练对国家足球联赛球队防守表现的影响

这项研究研究了防守协调员和主教练对国家橄榄球联盟（NFL）球队防守表现的影响。我们发现，精英且非常差劲的防守协调员和主教练会对他们的球队的防守表现产生有意义的影响。事实证明，随着防守协调员任期的增加，球队的防守表现也会提高。同样，与没有NFL球员经验的教练相比，作为NFL球员的防守协调员和主教练对提高防守表现也有贡献。此外，与4-3防御路线相比，发现3-4防御路线与改善的防守表现相关。