University of Pennsylvania ScholarlyCommons Statistics Papers Wharton Faculty Research 6-2016 Estimating an NBA Player’s Impact on is Team’s Chances of Winning Sameer K. Deshpande University of Pennsylvania Shane T. Jensen University of Pennsylvania Follow this and additional works at: https://repository.upenn.edu/statistics_papers Part of the Physical Sciences and Mathematics Commons Recommended Citation Deshpande, S. K., & Jensen, S. T. (2016). Estimating an NBA Player’s Impact on is Team’s Chances of Winning. Journal of Quantitative Analysis in Sports, 12 (2), 51-72. http://dx.doi.org/10.1515/ jqas-2015-0027 This paper is posted at ScholarlyCommons. https://repository.upenn.edu/statistics_papers/85 For more information, please contact
[email protected]. Estimating an NBA Player’s Impact on is Team’s Chances of Winning Abstract Traditional NBA player evaluation metrics are based on scoring differential or some pace-adjusted linear combination of box score statistics like points, rebounds, assists, etc. These measures treat performances with the outcome of the game still in question (e.g. tie score with five minutes left) in exactly the same way as they treat performances with the outcome virtually decided (e.g. when one team leads by 30 points with one minute left). Because they ignore the context in which players perform, these measures can result in misleading estimates of how players help their teams win. We instead use a win probability framework for evaluating the impact NBA players have on their teams’ chances of winning. We propose a Bayesian linear regression model to estimate an individual player’s impact, after controlling for the other players on the court.