Matter of Stats

View Original

2024 : Simulating the Final Ladder After Round 11

Tony Corke

This year’s post Round 11 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. Sydney: 99% chances of being finalists; 95% chances of Top 4; 75% chances of being Minor Premier

  2. Carlton and Melbourne: 75-80% chances of being finalists; 40% chances of Top 4; 4% chances of being Minor Premier

  3. Collingwood, Port Adelaide, and Geelong: 70% chances of being finalists; 35% chances of Top 4; 3-4% chances of being Minor Premier

  4. Essendon and GWS: 60-65% chances of being finalists; 25-30% chances of Top 4; 2-4% chances of being Minor Premier

  5. Fremantle, Gold Coast, and Western Bulldogs: 45-50% chances of being finalists; 15-20% chances of Top 4; 0.5-1% chances of being Minor Premier

  6. Brisbane Lions: 35% chance of being finalists; 10% chance of Top 4; none or virtually no chance of being Minor Premier

  7. Adelaide: 15-20% chance of being finalists; 3% chance of Top 4; none or virtually no chance of being Minor Premier

  8. Hawthorn: 5% chance of being finalists; 0.5% chance of Top 4; no chance of being Minor Premier

  9. St Kilda and West Coast: 0.5-1% chance of being finalists; tiny chance of Top 4; no chance of being Minor Premier

  10. Richmond and North Melbourne: no chance of being finalists; no chance of Top 4; no chance of being Minor Premier

LADDER FINISHES

The ladder projections using the Heretical outputs appear below.

There were a few large movements in teams’ Final chances this week, with GWS’ Finals chances rising most substantially (15% points), and Brisbane Lions’ (16% points), and Geelong’s (11% points) falling most substantially.

There are now only 11 teams with a near 50% or better chance of playing Finals, and eight teams with a near 25% or higher chance of finishing Top 4.

TEAM AND POSITION CONCENTRATION

The HHI figures for the latest 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

Uncertainty fell this week - returning to around Round 9 levels - with the 11 least certain teams now effectively fighting for between about 11 and 13 ladder positions, and the 11 least certain ladder positions having 10.5 to 13 teams effectively fighting for them.

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

The ladder positions with the most uncertainty remain those in the middle of the table, from about 3rd to 13th.

We also see that the average team is effectively competing for about 9.2 positions, and the average ladder position has about 9.1 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: 10% had 12 wins (down 1%), 44% had 13 wins (up 2%), and 17% had 12.5 wins (also, virtually none had 11 wins, and 17% had 12.5 wins).

  • For teams finishing 4th in a replicate: 43% had 15 wins (up 3%), 17% had 16 wins (no change), and 12% had 15.5 wins (also, 12% had 14 wins, and 13% had 14.5 wins).

To me, it still looks like 13 wins will be needed to play Finals, and possibly 15 will be good enough for Top 4.

Looked at another way:

  • For teams finishing win 11 wins: 0% made Finals (no change)

  • For teams finishing win 12 wins: 10% made Finals (down 1%)

  • For teams finishing win 13 wins: 66% made Finals (no change)

  • For teams finishing win 14 wins: 98% made Finals and 10% finished Top 4 (up 2%)

  • For teams finishing win 15 wins: 62% finished Top 4 (up 4%)

  • For teams finishing win 16 wins: 96% finished Top 4 (up 1%)

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 about a 3-in-8 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 (up by about 1.5% on last week)

  • There’s now about a 1-in-8 chance that 1st will be decided on percentages (down by about 1% on last week)

FINALS CHANCES

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