Matter of Stats

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2023 : Simulating the Final Ladder After Round 2

This weeks’ simulation shows an even greater levelling of the playing field, with 8 teams enjoying better than 60% chances of playing Finals, better than 30% chances of finishing Top 4, and better than 5% chances of finishing as Minor Premiers.

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

  1. Collingwood and Sydney: 85 to 90% chance of being a finalist; 60 to 70% chance of finishing Top 4; and 20 to 30% chance of being Minor Premier

  2. Carlton, Geelong, Richmond, Port Adelaide, Melbourne, and St Kilda: 60 to 70% chance of being a finalist; 30 to 40% chance of finishing Top 4; and 6 to 8% chance of being Minor Premier

  3. Brisbane Lions: 50% chance of being a finalist; 20% chance of finishing Top 4; and 3% chance of being Minor Premier

  4. Essendon: 40% chance of being a finalist; 15% chance of finishing Top 4; and 2% chance of being Minor Premier

  5. Fremantle, Western Bulldogs, Adelaide, and GWS: 20 to 30% chance of being a finalist; 5 to 8% chance of finishing Top 4; and 0.5 to 1% chance of being Minor Premier

  6. Gold Coast, North Melbourne, and West Coast: 10 to 15% chance of being a finalist; 1.5 to 3% chance of finishing Top 4; and 0.1 to 0.2% chance of being Minor Premier

  7. Hawthorn: 6% chance of being a finalist; 1% chance of finishing Top 4; and 0.1% 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 or higher for Collingwood, Sydney, Carlton, St Kilda, Brisbane Lions, North Melbourne, and West Coast, and -1 or lesser for Geelong, Port Adelaide, Melbourne, Fremantle, Western Bulldogs, and GWS.

The range of expected wins now runs from 6.6 to 16.5 (up 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 14 and 16 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 now West Coast, Sydney, Collingwood, and Hawthorn, and on the ladder positions side, those with least uncertainty are 1st, 2nd, 17th, and 18th.

We see that the ladder positions with the most uncertainty remain 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 charts below investigate the relationships between ladder position and number of wins.

Firstly, we show the relationships by team, which mostly shows the broad range of possible outcomes that still remain for every team, but also shows some level of concentration for most teams.

Next, we show the relationships after aggregating across teams.

Based on the simulations, we can say that:

  • For teams finishing 8th in a replicate: 29% had 12 wins (up 2%), 30% had 13 wins (down 1%), and 14% had 12.5 wins (up 1%)

  • For teams finishing 4th in a replicate: 26% had 15 wins (up 1%), 26% had 16 wins (down 2%), and 12% had 15.5 wins (no change). Also 8% had 14 wins (up 1%), and 7% had 14.5 wins (up 1%)

  • For teams finishing win 11 wins: 7% made Finals (up 1%)

  • For teams finishing win 12 wins: 41% made Finals (up 3%)

  • For teams finishing win 13 wins: 85% made Finals (up 3%)

  • For teams finishing win 14 wins: 99% made Finals (up 1%)

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 still just less than a 1-in-3 chance that 8th will be decided on percentages

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

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

FINALS CHANCES

Finally we take a fresh and still plainly premature look 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 Collingwood now clear favourites for the Flag at around 2-in-9 chances, ahead of Sydney (1-in-7), Geelong (1-in-9), Richmond (1-in-10), Melbourne (1-in-11), and Carlton (1-in-12).