Frame by frame completion probability of an American football pass

• Autor(a) principal: Silva, Gustavo Pompeu da
• Data de Publicação: 2022
• Tipo de documento: Dissertação
• Idioma: eng
• Título da fonte: Biblioteca Digital de Teses e Dissertações da USP
• Texto Completo: https://www.teses.usp.br/teses/disponiveis/11/11134/tde-07042022-155700/
• topic: Aprendizado de máquinas; Machine learning; National Football League; National Football League; R Software; Random forest; Random forest; Software R

American football is an increasingly popular sport, with a growing audience in many countries in the world. The most watched American football league in the world is the United States’ National Football League (NFL), where every offensive play can be either a run or a pass, and in this dissertation, it is the pass that matters. Not all pass plays in the NFL are created equal, many factors can affect the probability of a pass completion, such as receiver separation from the nearest defender, distance from receiver to passer, offensive formation, game score, among many others. When predicting the completion probability of a pass, it is essential to know who the target of the pass is. By using distance measures between players and the ball, it is possible to calculate empirical probabilities and predict very accurately who the target will be. The big question is: how likely is it for a pass to be completed in an NFL match while the ball is in the air? We develop a machine learning algorithm to answer this based on the aforementioned predictors. Using data from the 2018 NFL season, we obtained conditional and marginal predictions for pass completion probability based on a random forest model. This is based on a two-stage procedure: firstly, we calculate the probability of each offensive player being the pass target, then conditional on the target, we predict completion probability based on the random forest model. Finally, the general completion probability can be calculated using the law of total probability. We present animations for selected plays and show the pass completion probability frame by frame.