Non-Metric Multidimensional Performance Indicator Scaling Reveals Seasonal and Team Dissimilarity within the National Rugby League

Woods, C. T.; Robertson, S.; Sinclair, W. H.; Collier, N. F.

Objectives:
The aim of this study was to analyze the dissimilarity of seasonal and team profiles within the National Rugby League (NRL) between the 2005 to 2016 seasons. By understanding these dynamics, the study sought to reveal the evolutionary patterns of game-play and highlight the similarity of individual team profiles.

Methods:
Total seasonal values for 15 performance indicators were collected for every NRL team over the analyzed period, resulting in 190 observations. Non-metric multidimensional scaling was utilized to uncover seasonal and team dissimilarity, providing insights into the changes in game-play over time and the distinct characteristics of each team.

Results:
Compared to the 2005 to 2011 seasons, the period from 2012 to 2016 exhibited a state of flux, with noticeable dissimilarities in the positioning of team profiles on the ordination surface. Notably, there was a significant change in performance indicator characteristics following the 2012 season. For instance, the 2014 season showed a substantial increase in total ‘all run metres’ and ‘kick return metres’, along with a decrease in ‘missed tackles’ and ‘tackle breaks’. Analysis of team ordination plots revealed that certain teams evolved in both similar and dissimilar ways over the studied period.

Conclusions:
The findings suggest that NRL match-types underwent evolution following the 2012 season and continue to be in a state of flux. This could be attributed to various factors such as modifications in coaching tactics and rule changes. Coaches can leverage these insights when designing future game strategies in the NRL, adapting to the evolving dynamics of the sport.