At one end of the scale, we have every NRL team. At the top level, we only see the short kick off when the clock is winding down and the team kicking off desperately needs points to remain in contention for the win. At the other end of the scale, we have the Ipswich Jets, coached by Shane and Ben Walker, who will indiscriminately use short kick-offs, short drop-outs and taking the two when it makes no sense to do so because that’s Walkerology. Are the Walker Brothers on to something that everyone else is missing?
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In 2018, I recorded a few outcomes for 1,000 sets of six. This sounds like a lot but it’s actually the equivalent of about twelve games of football. I looked at where the set started, what the end result of the set was (e.g. error, score, fifth tackle kick) and a few other details.
The biggest problem I face in trying to work through rugby league analytics is a lack of useful, reliable, easy to source data to analyse. For this post, I had to do it myself.
I recorded 1,000 sets of six from the 2018 season so far, ranging from a Titans-Warriors pre-season game and finishing during the Titans-Bulldogs game in round 15. A thousand may sound like a lot but given there are about 80 sets of six per game, it’s about a dozen games worth of material. We are working with a relatively small sample size and that the probabilities we estimate may not precisely align with reality. If I had the time and patience (a salary could substitute for time and patience), I could go through the entire history of the NRL and do a better job. This site’s motto is “you get what you pay for”.
But today is not about solving problems once and forever. There are a number of ways to solve a given problem and the techniques and data presented here are hopefully what will be a foundation to build upon. This post is about demonstrating that rugby league can be analysed statistically and useful conclusions can be drawn.