Sunday, June 24, 2018

AFL Power Rankings: Round 14 2018

The AFL tries to give the weaker teams the easier fixtures, and the stronger teams more difficult match-ups. However, teams rise and fall – who has got lucky in 2018 from their fixture becoming easier than expected?



Whenever the AFL fixture for the new season is released there are several ratings of the difficulty of each team’s fixture, including on this blog. Less often do you see the ratings revisited though, once we find out how strong each team is in this season, rather than how strong they were last season.

How the fixture was meant to work in 2018

In a season where each of the 18 AFL teams plays 22 matches, each team can only play five others twice. The AFL attempts to make the fixture more equitable by applying a ‘weighted rule’ to these ‘double match-ups’. Basically the 18 teams are divided into three groups of six based on how they finished after finals in 2017. Teams will tend to have more ‘double match-ups’ against teams in their own group, and less against teams at the other end of the spectrum.

This is who each team plays twice in 2018.

Ladder position sometimes hides the ‘true’ relative strength of a side. Nevertheless the AFL got pretty much what they intended in terms of matching each team’s strength with the combined strength of the teams they play twice, based on rankings at the end of 2017 (see table below). The main exceptions were that ‘middle six’ side the Western Bulldogs probably got an easier set of ‘double match-ups’ than ‘bottom six’ side Fremantle, and that ‘middle six’ side St. Kilda got a set that was closer to a ‘top six’ side.

(Note that, in the table below, combined ranking points have been reversed so higher points means an easier fixture. Also, points were adjusted so that their sum is zero.)

How the fixture has ended up working in 2018

Of course though teams improve and decline, and so the strength of the fixture at the start of the season is different to how it actually turns out. In 2018 the teams that have improved the most include North Melbourne, Melbourne, Fremantle, Collingwood, and West Coast (see table below). Facing these sides twice is now a tougher prospect than it first appeared. Conversely the biggest declines in performance have been from Adelaide, St. Kilda, the Western Bulldogs, and Carlton.


If we re-rank the strength of each team’s ‘double match-ups’ we see some significant changes for some teams (see table below).


Top sides Richmond and GWS now have much weaker fixtures than originally intended, as they play Adelaide and St. Kilda twice. Their fixtures are now closer to ‘middle six’ sides.

Meanwhile St. Kilda and the Western Bulldogs now have much stronger fixtures than originally intended, as they play Melbourne and North Melbourne twice. Their fixtures are now closer to ‘top six’ sides. So is Essendon’s, due to improvements in the performances of Collingwood, Fremantle, and Hawthorn.

Melbourne and North Melbourne – which had an easy set of return matches already – have benefitted the most from changes in form in 2018. Of the five teams North Melbourne play twice, four of them are amongst the five current weakest teams: Gold Coast, Brisbane, the Western Bulldogs, and St. Kilda. Two of those sides – the Dogs and Saints – were ‘middle of the pack’ sides when the fixture was originally constructed. Melbourne plays three of the big decliners twice - the Dogs, Saints, and Adelaide.

Ultimately the fixture doesn’t turn you from a ‘good’ side to a ‘bad’ side, or vice versa. St. Kilda, the Western Bulldogs, and Essendon – all currently outside the eight – probably would have a low chance of making the finals even with a friendlier fixture. But it can help you at the margins. For North Melbourne, currently sitting eighth, it may mean the difference between making the finals and missing out. The Kangaroos beat the Dogs by just two points on the weekend; against an opponent that was any stronger they may not have snuck home.

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