The expected value of possession in professional rugby league match-play |
| |
Authors: | Thomas Kempton Nicholas Kennedy Aaron J Coutts |
| |
Institution: | 1. Sport &2. Exercise Discipline Group, Faculty of Health, University of Technology (UTS), Sydney, Australia;3. Panthers Rugby League Football Club, Sydney, Australia |
| |
Abstract: | This study estimated the expected point value for starting possessions in different field locations during rugby league match-play and calculated the mean expected points for each subsequent play during the possession. It also examined the origin of tries scored according to the method of gaining possession. Play-by-play data were taken from all 768 regular-season National Rugby League (NRL) matches during 2010–2013. A probabilistic model estimated the expected point outcome based on the net difference in points scored by a team in possession in a given situation. An iterative method was used to approximate the value of each situation based on actual scoring outcomes. Possessions commencing close to the opposition’s goal-line had the highest expected point equity, which decreased as the location of the possession moved towards the team’s own goal-line. Possessions following an opposition error, penalty or goal-line dropout had the highest likelihood of a try being scored on the set subsequent to their occurrence. In contrast, possessions that follow an opposition completed set or a restart were least likely to result in a try. The expected point values framework from our model has applications for informing playing strategy and assessing individual and team performance in professional rugby league. |
| |
Keywords: | Team sport performance analysis tactics analytics |
|
|