Team-bounded DEA efficiency scores: The case of UEFA Champions League Players

Each player puts in time and effort to achieve results during a game, which can contribute to the team?s overall score. However, the combined effort of the whole team is a hidden factor that impacts a player?s outcomes. With this in mind, the aim of this study is to improve the DEA methodology by considering team performance when calculating efficiency scores. In this study, we introduce a new way to estimate efficiency using data envelopment analysis, which takes into account how the team performs. To achieve this, we use a single mathematical model that limits the player?s efficiency score based on the team performance. This ensures that the efficiency score cannot be more than ? times the average team efficiency score. The results from applying this new model to the UEFA Champions League 2021/22 season indicate that inefficient teammates significantly impact efficiency scores. However, when the entire team performs well, any decrease in efficiency scores is not substantial. The key advantage of these new efficiency scores is that they help pinpoint weak links within each team and identify areas that need improvement to enhance individual efficiency. Consequently, coaches and managers can utilize this model to identify areas for team enhancement, as well as players to improve their performance.