If you’re not interested in how the rankings work and just want to see the outputs, click here.
It began as a simple exercise to try and rate Super League players, much in the way that I rate NRL and Queensland Cup players. It turns out that the Super League website makes that an impossible task because it is a garbage fire for stats. Moving on from the wasted effort, I thought I might still do team ratings for the RFL system, mostly out of my increased interest with the Toronto Wolfpack’s promotion into Super League.
Then I thought about the Kaiviti Silktails of Fiji entering into the New South Wales system and wondered if I should take a look at the leagues there, despite my dubiousness about whether anyone in NSW cared about lower grade football when they could follow the Dragons, the Tigers or the Knights in so-called first grade.
From there I spiralled into a mishmash of US college football tradition, websites in Serbian and copying and pasting. When I came to, I had a neatly formatted spreadsheet covering a decade of world club rugby league.
Ranking the world
Invariably, creating any sort of evaluation system requires judgements by the evaluator about who to include or exclude and what the evaluation system considers to be “good”. I’ll explain my position and you can decide whether or not you like it.
Scoring the teams uses an average of four similar rating systems that look at performance over different time intervals.
We’ve long had form and class Elo ratings for the NRL and Queensland Cup. Form is about the short term performance of clubs, and can represent anywhere from four to eight weeks of results depending on the draw and league, while class is about long term performance, and can represent the average of years of performance. Form is a better predictor of match results, class is a better predictor of fan disappointment.
I created similar systems for another ten leagues in NSW, PNG, France (see also my Elite 1 season preview), the UK and the USA. They work along the same lines as the NRL and Queensland Cup editions. The average rating within an Elo system is approximately 1500 and the disparity in ratings can be used to estimate match outcome probabilities.
Both sets of Elo ratings are adjusted by a classification system I borrowed from baseball. To acknowledge the fact that a 1700 team in the BRL is not likely to be as good as a 1300 team in Super League, we adjust the team ratings so we can attempt to compare apples to apples –
- Majors: NRL (ratings adjusted by +500) & Super League (+380)
- Triple-A (AAA): QCup, NSW Cup and RFL Championship (all +85)
- Double-A (AA): Ron Massey, RFL League 1, FFR Elite 1 (all -300)
- High-A (A+): Brisbane RL, FFR Elite 2 (all -700)
- Low-A (A-): USARL (-1000)
In Elo terms, a difference of 120 points between teams, like between an average NRL and an average Super League team, makes the NRL team 2:1 favourites. A 415 point gap gives the less favoured team a 8.4% chance of winning (equivalent to the replacement level), 800 points 1%, 1200 points 0.1% and 1600 points 0.01%. Consider the improbability of the Jacksonville Axemen beating the Melbourne Storm and you get an idea of where I’m coming from.
Between short term form and long term class, we’re missing a medium term component that represents roughly a single year of performance. I originally was going to create Poseidon ratings for the leagues, so I took a simpler approach and used points scored per game and points conceded per game over a regular season in lieu.
I then made my simplification much more complicated by doing a linear regression of winning percentage across all leagues compared to points scored per game and a second regression against points conceded per game. This gives a formula that converts the components of for and against into winning percentage, which is in turn converted to an equivalent Elo rating, which is then adjusted per the above. It also allows me to compare points scored per game – as a measure of competitiveness or quality or both? – across different leagues.
This specifically is just trivia but from an overall analytics perspective, the risk is if only the top league is analysed and analysts assume that the same principles apply to all leagues, incorrect conclusions will be drawn about the sport.
The ranking is decided by which team has the highest average score across the four rating components, which are given equal weighting. I call it the Global Rugby League Football Club Rankings, or GRLFC for short.
While it’s possible for teams to game a single system, it would be nigh on impossible to game all components, so I feel relatively comfortable that the highest ranked team is the “best”.
That said, form ratings and the for-and-against components only work on regular season results. Class ratings are the only component that takes into account playoff (and Challenge Cup, where applicable) performance. You may think finals footy deserve more weighting but I would put it to you that “the grand final winner is always the best team” and “any rugby league team can win on their day” are two mutually exclusive thoughts and I prefer to believe the latter. If you want to further mull it over, consider that Newtown finished seventh on the ladder in the twelve team NSW Cup in 2019 and then went on to win the Cup and then the State Championship.
Each club (as represented by their combination of name, colours and logo) is only represented once in each year’s rankings, by the version of that club in the highest league. For example, Wentworthville have been in the NSW Cup and the lower tier Ron Massey Cup. To date, Wenty have been represented in the rankings by their state cup team. However, as the Magpies will be replaced in the NSW Cup by Parra reserve grade in 2020, and while this doesn’t change much in reality, they will be henceforth represented in the rankings by their Ron Massey team. This is mostly because it makes the rankings a little more interesting, not having been clogged up by a half dozen clones of the NSWRL clubs.
I would like to have included the Auckland Rugby League’s Fox Memorial comp as a double-A league but it seems to be impossible to find scores. I also would have liked to add more low-A comps, like those in Serbia or Netherlands or maybe even Nigeria or Kenya, but scores for these comps are even more difficult to find or have incomplete results or don’t really play enough games. As a result, we may never know whether the Otahuhu Leopards are better than the Villeneuve Léopards.
I drove myself mad enough to trying to get the results that I did. I don’t feel the need to delve further into district comps in Australia but, who knows, I may well change my mind on that. It would be nice to go further back on some comps, particularly in France and PNG, but we have what we have. A big thanks to rugbyleagueproject.org, leagueunlimited.com and treizemondial.fr for hosting what they do have, because we can’t possibly rely on federations to have curated their own records and history.
A full season of results is required for a club to be ranked. This is only a problem for French clubs, with both Elite 1 and 2 running through their winter and the date the ranking is nominally calculated is December 31. A French club’s first part season is given a provisional place in the rankings, converting to a ranking the year after, based on the previous twelve months’ worth of results.
The rankings can be seen for 2009 through 2019 here. Your current top seeds in each competition are –
- NRL (Major): Melbourne Storm (1)
- Super League (Major): St Helens (5)
- Championship (AAA): Toronto Wolfpack (29)
- Queensland Cup (AAA): Sunshine Coast Falcons (30)
- NSW Cup (AAA): Newtown Jets (40)
- Ron Massey (AA): St Marys (63)
- League 1 (AA): Oldham Roughyeds (64)
- PNG NRLC (AA): Lae Tigers (66)
- Elite 1 (AA): Albi Tigers (69)
- Elite 2 (A+): Villegailhenc-Aragon (101)
- BRL (A+): West Brisbane Panthers (105)
- USARL (A-): Jacksonville Axemen (109)
In an ideal world, we’d have a women’s ranking to complement the men’s. But the NRLW has only completed 14 games, which is not a sufficient sample although we may see that double in 2020. The QRLW will only commence this year and it remains to be seen what the NSWRL is going to do with their women’s premiership, whether this becomes the equivalent of a Ron Massey Cup to a new NSWRLW/women’s NSW Cup or if, as is usually the case, the Sydney comp will be promoted to be the state comp.
In the more enlightened Europe, the women’s Super League has completed its first season, comprising 14 rounds, and the Elite Feminine has just commenced its second season, the previous being 12 rounds. The bones are there for a women’s club ranking, but it will take time for Australia to catch up a little and make the rankings more balanced. With any luck, I should be able to deliver the first rankings at the end of this year.
The World Club Challenge
International club football is a rare thing, indeed. The ridiculously lopsided 1997 World Club Challenge (Australian clubs scored 2506 points to the Europeans’ 957) largely put paid to the idea that there could be a competition on an equal footing between the two major leagues of football. Other than a short lived World Club Series, which was overly reliant on the charity of big Australian clubs, all that remains of the concept is the World Club Challenge match-up between the winners of the Super League and the NRL.
First held irregularly since 1976 and annually since 2000, the match suffers from the disparity in the quality of the leagues – obviously driven by money – and a lack of interest – largely driven by a lack of promotion and lack of commitment from most Australian clubs. The advantage has ebbed and flowed, generally in favour of the Australian sides but in the late 2000s, the English fought back before being pummelled back into submission more recently.
Incidentally, I arrived at a 120 point discount between the NRL and Super League based on Super League clubs’ for and against in the WCC over the last twenty years. The application of Pythagorean expectation and then converting that (approx. 33% win percentage for SL) into Elo rating points.
Still, I believe that the WCC should be one of the centrepieces of the season, not unlike an abbreviated World Series or Super Bowl. A match day programme could be filled out by play-offs from the champions of the men’s, women’s and secondary men’s comps – perhaps with the winners of the NRL State Championship and the winner of a play-off of the premiers of the RFL Championship and Elite 1 – in the Pacific and the Atlantic. Such an event could be saleable to broadcasters, sponsors and hosts.
Of course, if successful, the WCC would then undermine the respective competitions’ grand final days, so there’s an obvious conflict of interest. The conflict is difficult to resolve when the stakeholders are more interested in maintaining their own position than making money or securing a commercial future. While cash may be a corrupting influence, the game will not survive as a professional sport without it.
Given the absence of international club fixtures, you could fairly wonder what the applications of this ranking system might be, other than to have a rough guess at whether the Gold Coast Titans are better or worse than the Sunshine Coast Falcons (the answer is: slightly better). My feel is that the final score is a rough proxy for a singular globalised Elo rating system. Consequently, it may not be very good but I looked back to the last ten WCCs.
It was successful in predicting the higher ranked team winning eight of the ten matches but not particularly predictive in terms of the gap between the teams (the trendline above shows basically zero correlation) nor in the scale of favouritism (favourites won 80% of the time compared to 65.9% predicted probability). Still, it’s only a sample size of ten games where the Super League sides have been beaten pretty comprehensively.
In the meantime, this gives the English something to work towards.