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2024 : Simulating the Final Ladder After Round 6

Tony Corke

This year’s post Round 4 simulations suggest that the teams can be roughly grouped as below:

(For anyone who is curious about the precise methodology I’ve employed, see this blog post over on the General Probability and Statistics journal)

  1. Geelong: 95% chances of being finalists; 80% chances of Top 4; 40% chances of being Minor Premier

  2. Carlton, GWS, Sydney, and Melbourne: 80% chances of being finalists; 50% chances of Top 4; 10% to 15% chances of being Minor Premier

  3. Port Adelaide, Collingwood, Brisbane Lions, and Western Bulldogs: 50-65% chances of being finalists; 15-25% chances of Top 4; 2-4% chances of being Minor Premier

  4. Essendon, Gold Coast, and Fremantle: 35-40% chance of being finalists; 10% chance of Top 4; 1% chance of being Minor Premier

  5. St Kilda: 20% chances of being finalists; 5% of Top 4; tiny chance of being Minor Premier

  6. Adelaide, West Coast, and Hawthorn: 5-10% chances of being finalists; 0.5-1.5% chance of Top 4; tiny chance of being Minor Premier

  7. Richmond: 2.5% chance of being finalists; tiny chance of Top 4; tiny chance of being Minor Premier

  8. North Melbourne: tiny chance of being finalists; no chance of Top 4 or Minor Premier

LADDER FINISHES

The ladder projections using the Heretical outputs appear below.

It was a week of unprecedently large movements in teams’ Final chances.

Fremantle’s, St Kilda’s, Adelaide’s, Port Adelaide’s, and Brisbane Lions’ Finals chances fell most substantially, with Fremantle’s decline from 69% to 36% the largest single-week decline for a team that I can remember.

Collingwood’s, Western Bulldogs’, Essendon’s, Sydney’s, and Carlton’s Finals chances rose most substantially.

There are still nine teams with about a 50% or higher chance of playing Finals, and 12 with about a 7-in-20 chance or higher. There are also eight teams with a 20% or higher chance of finishing Top 4, and five with a 10% or better chance of taking the Minor Premiership.

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

Overall ladder uncertainty decreased only fractionally this week, with the majority of teams still effectively fighting for between 11 and 14 ladder positions, and most ladder positions having 11 to 14.5 teams effectively fighting for them.

On the teams side, the largest exceptions are North Melbourne, Geelong, Richmond, and Hawthorn, while on the ladder positions side, the largest exceptions are 1st, 2nd, 16th, 17th, and 18th.

Tthe ladder positions with the most uncertainty are those in the middle of the table, from about 4th to 14th.

We also see that the average team is effectively competing for about 10.7 positions, and the average ladder position has about 10.7 teams competing for it.

WINS AND LADDER POSITION

Let’s look at the number of wins MoSHBODS thinks will be sufficient for given ladder positions.

Based on the simulations, we can say that:

  • For teams finishing 8th in a replicate: 30% had 12 wins (up 7%), 41% had 13 wins (down 2%), and 8% had 12.5 wins (also, 2% had 11 wins, and 8% had 12.5 wins). Those suggest that the team finishing 8th is now slightly more likely to have recorded only 12 wins.

  • For teams finishing 4th in a replicate: 37% had 15 wins (up 4%), 29% had 16 wins (down 5%), and 7% had 15.5 wins (also, 11% had 14 wins, and 4% had 14.5 wins). Those suggest that the team finishing 4th is now slightly more likely to have recorded only 15 wins.

Looked at another way:

  • For teams finishing win 11 wins: 3% made Finals (up 1%)

  • For teams finishing win 12 wins: 31% made Finals (up 7%)

  • For teams finishing win 13 wins: 80% made Finals (up 7%)

  • For teams finishing win 14 wins: 99% made Finals and 10% finished Top 4 (up 3%)

  • For teams finishing win 15 wins: 49% finished Top 4 (up 10%)

  • For teams finishing win 16 wins: 88% finished Top 4 (up 5%)

Here’s what it looks like on a team-by-team basis:

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 current estimates are that:

  • There’s now almost a 2-in-5 chance that 8th will be decided on percentages (up by about 1% on last week)

  • There’s now about a 7-in-20 chance that 4th will be decided on percentages (down by about 1% on last week)

  • There’s now about a 1-in-6 chance that 1st will be decided on percentages (down by almost 3% on last week)

FINALS CHANCES

Finally, here’s what the simulations provide by way of finals-related probabilities