Developing Measurable Methodologies to Record And
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Quantifying team and individual performance and their impact on try scoring in rugby union Lim Tze Yang, Eugene “This thesis is presented for the degree of Master of Science at The University of Western Australia” School of Sport Science, Exercise and Health Faculty of Life and Physical Sciences Submitted September, 2011 i Acknowledgements i. Thank you to my family. Without your support and understanding, I would not have been here in the first place and definitely not have made it this far. Looking back all those years, who would have put money on a thesis! ii. Thank you to my supervisors Asst/Prof Brendan Lay, W/Prof Brian Dawson and Assoc/Prof Karen Wallman. I am eternally indebted to you not just for your knowledge, guidance and mentorship but especially also for the vast amount of patience you had. Not being the easiest nor most self-driven student to work with, I have never failed to constantly remind myself just how much I appreciated each time you were so ready to meet me and for all the invaluable feedback and lessons I have learnt from you. Thank you for not giving up. iii. Thank you to Scott Anderson, without you none of this research would have been possible. You have given me an insight into professional sport that I would otherwise never have had the opportunity to experience. I have learnt a great deal from your mentorship and most importantly, your friendship. iv. Thank you to John Inverarity and Richard Pengelley. Your mentorship, friendship, countless chats and advice will stay with me always. You have never failed to lend a helping hand or a listening ear and have always been ready on deck. It has been my utmost good fortune to have met and worked with you and I look forward to our continued friendship. v. Thank you to the staff of St. George’s College. I might as well have become a permanent fixture at this lovely institution. And although it has been said many times already, it is true that an institution can only become what it is because of the people that make it up. From the friendly faces, to the daily gossip, cleaning my room, providing food, administrative dealings, forwarding of mail and many more too long to list, you guys have been an absolute integral part of my journey. vi. Thank you Sara. Time has ticked by so quickly from the time we started out as Freshers! You have been there this whole time and have listened to all my rants and raves. Bet you’re just as relieved as I am that this chapter is finally coming to a proper close. ii vii. Thank you to everyone I have met along this journey. I have met countless people, hundreds of friends, bumped up my Facebook friends quota by heaps, performed on stage, been silly, been serious and just have had the most amazing time. I owe it to each and every single one of you that I have met over this time. iii Abstract This thesis presents itself in two parts. First, a Player Impact Ranking (PIR) matrix to objectively quantify the impact of players on team performance and game outcomes in rugby union was designed and implemented. Next, by utilising the PIR as a developmental platform for constructing a Team Attacking Superiority (TAS) scoring system, it was determined if consecutive periods of attacking superiority, as presented by the TAS, could predict try scoring in rugby union. Game data from the Crusaders, Force and Lions in the 2006, 2007 and 2008 Super 14 competition seasons were used. A framework of game actions was developed for individual players and allocated positive and negative weightings to reflect each game action’s relative importance to a team’s winning performance. The weightings were applied to the frequencies of each game action to derive a total net game performance (NGP) score, which was then used to assess the teams’ performances, utilising game results (i.e. win/loss), competition points and score margins (i.e. the difference in scores between two teams). NGP scores showed significant relationships with wins/losses, team scores and competition points (p<0.05). Moderate, positive correlations were associated with NGP scores and score margins (r=0.66-0.76; p<0.01). Results suggested that the derived PIR matrix accurately reflected game results and team performances, making it a useful tool for post match analysis of performance. The PIR matrix was subsequently condensed to create a Team Impact Ranking (TIR) matrix, which was used to calculate the TAS to measure consecutive periods of attacking dominance by a team. Our results showed that 67% of tries scored resulted from teams maintaining 3 TAS periods or less. Although the majority of tries scored were from less TAS periods, odd ratios revealed that teams were more likely to convert TAS periods into tries scored if they were able to attain higher numbers of TAS periods. Further research into applying the PIR matrix and TAS scoring system developed here to in-match situations for real time analysis is recommended. iv Publication(s) arising from this thesis: Lim, E., Lay, B., Dawson, B., Wallman, K. and Anderson, S. (2009). Development of a player impact ranking matrix in Super 14 rugby union. International Journal of Performance Analysis in Sport, 9(3), 354-367. Lim, E., Lay, B., Dawson, B., Wallman, K. and Anderson, S. (2011). Predicting try scoring in super 14 rugby union – the development of a superior attacking team scoring system. Manuscript submitted for publication. v Table of Contents CHAPTER 1 .................................................................................................................1 1.0 General introduction and literature review ............................................................................. 1 2.0 Performance analysis in rugby union ....................................................................................... 3 2.1 Performance analysis in rugby union ................................................................................................. 4 2.2 Rugby union – a beginner’s guide to the game ................................................................................... 4 2.3 Tackles, rucks, mauls and turnovers ................................................................................................ 5 2.4 Position on field where possession is gained ........................................................................................ 6 2.5 Position on the field where points were scored from and origins of movements that led to scoring opportunities .......................................................................................................................................... 7 2.6 Number of passes preceding successful tries ........................................................................................ 8 2.7 Timing of tries scored ....................................................................................................................... 8 2.8 Possession and movement time .......................................................................................................... 8 2.9 A different approach towards the analysis of rugby union ................................................................ 10 3.0 Issues, discrepancies and methodologies related to notational analysis in team sports . 10 3.1 Sample size ................................................................................................................................... 11 3.2 Operational definitions ................................................................................................................... 11 3.3 Quantity vs quality of notated actions ............................................................................................. 12 4.0 Aims of this project .................................................................................................................. 12 CHAPTER 2: Development of a player impact ranking matrix in Super 14 rugby union ........................................................................................................................... 15 1.0 Introduction ............................................................................................................................... 17 1.1 Performance Indicators (PI) in rugby union .................................................................................... 18 2.0 Methods ...................................................................................................................................... 19 2.1 Study design and data sample ........................................................................................................ 19 2.2 Identification of individual game actions (GA) .............................................................................. 20 2.3 Competition points ......................................................................................................................... 20 2.4 Positive vs negative GA ratio ......................................................................................................... 21 2.5 Positional differences ...................................................................................................................... 21 2.6 Reliability ...................................................................................................................................... 22 2.7 Statistical analysis ......................................................................................................................... 23 3.0 Results........................................................................................................................................