Matter of Stats

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2023 : Simulating the Final Ladder After Round 1

The overwhelming feature of the latest simulations is the apparent levelling of the playing field they suggest, especially in terms of which team might take out the Minor Premiership.

Those simulations suggest that the teams can now be roughly grouped as follows:

  1. Collingwood, Geelong, Sydney, Port Adelaide, and Melbourne: 75 to 80% chance of being a finalist; 14% to 16% chance of being Minor Premier

  2. Richmond and Carlton: 55 to 60% chance of being a finalist; 4 to 7% chance of being Minor Premier

  3. St Kilda, Fremantle, Brisbane Lions, Western Bulldogs, Essendon, and GWS: 30 to 45% chance of being a finalist; 1.4% to 3.2% chance of being Minor Premier

  4. Adelaide: 25% chance of being a finalist; 1% chance of being Minor Premier

  5. Gold Coast: 20% chance of being a finalist; 0.5% chance of being Minor Premier

  6. Hawthorn, North Melbourne, and West Coast: 6 to 9% chance of being a finalist; 0.2% or less chance of being Minor Premier

(For anyone who is curious about the precise methodology used for these simulations, please refer to this blog post over on the General Probability and Statistics journal)

LADDER FINISHES

The ladder projections using the Heretical outputs appear below.

We see some quite large changes in Expected Win values for some teams - as much as +1.6 or higher for Port Adelaide, Melbourne, Essendon, Collingwood, and Sydney, and as much as -1.6 or lower for Brisbane Lions, Western Bulldogs, Hawthorn, Geelong, and Gold Coast.

The range of expected wins now runs from 6.6 to 15.1.

TEAM AND POSITION CONCENTRATION

The HHI figures for these pre-season simulation replicates appear below. These provide us with estimates of:

  • How many ladder positions a team is currently effectively fighting for

  • How many teams are currently effectively fighting for a given ladder position

HERETICAL METHODOLOGY

We can see that about half of the teams are currently effectively fighting for between 15 and 17 ladder positions, and that about half the ladder positions have 14 to 17 teams effectively fighting for them.

On the teams side, those with least uncertainty are West Coast, North Melbourne, and Hawthorn, and on the ladder positions side,those with least uncertainty are 1st, 17th, and 18th.

We see that the ladder positions with the most uncertainty are, as is tradition, those in the middle of the table, from about 6th to 13th.

We also see that the average team is effectively competing for 13 positions, and the average ladder position has about 13 teams competing for it.

WINS AND LADDER POSITION

The chart below investigates the relationship between ladder position and number of wins.

Based on the simulations, we can say that:

  • For teams finishing 8th in a replicate: 27% had 12 wins, 31% had 13 wins, and 13% had 12.5 wins

  • For teams finishing 4th in a replicate: 25% had 15 wins, 28% had 16 wins, and 12% had 15.5 wins (also 7% had 14 wins, and 6% had 14.5 wins)

  • For teams finishing win 11 wins: 6% made Finals

  • For teams finishing win 12 wins: 38% made Finals

  • For teams finishing win 13 wins: 82% made Finals

  • For teams finishing win 14 wins: 98% made Finals

LIKELY IMPORTANCE OF PERCENTAGE

Next, we’ll use the simulations to investigate the estimated likelihood that any given pair of ladder positions will be determined after Round 24 based on percentage.

So, our new estimates are that:

  • There’s about a 1-in-3 chance that 8th will be decided on percentages

  • There’s about a 1-in-4 chance that 4th will be decided on percentages

  • There’s about a 1-in-7 chance that 1st will be decided on percentages

FINALS CHANCES

Finally this week we take a ridiculously premature looks at team’s chances all the way through to the Grand Final, making reasonable assumptions about where Finals will be played given the participants and week of the Finals.

We have Geelong and Collingwood now roughly equal favourites for the Flag at around 1-in-6 chances ahead of Port Adelaide, Sydney, and Melbourne with roughly 1-in-8 to 1-in-9 chances, with Richmond (1-in-10) and then Carlton (1-in-16) each forming their own tiers.

Thereafter follow a number of teams with roughly 1-in-33 to 1-in-100 chances for the Flag, leaving North Melbourne and West Coast with 1-in-500 chances.