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2024 : Simulating the Final Ladder After Round 16

Tony Corke

This year’s post Round 16 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: virtually certain of being finalists; 99.7% chances of Top 4; 90% chances of being Minor Premier

  2. Carlton: 99% chances of being finalists; 90% chances of Top 4; 10% chances of being Minor Premier

  3. Fremantle and Brisbane Lions : 85-90% chances of being finalists; 45-60% chances of Top 4; 0.5-1% chances of being Minor Premier

  4. Geelong: 75% chances of being finalists; 25-30% chances of Top 4; slim chances of being Minor Premier

  5. Collingwood, Essendon, Western Bulldogs, and Gold Coast: 45-60% chances of being finalists; 10-20% chances of Top 4; slim chances of being Minor Premier

  6. Port Adelaide, Hawthorn, Melbourne, and GWS: 30-40% chance of being finalists; 5% chance of Top 4; no or tiny chance of being Minor Premier

  7. Adelaide and St Kilda: 0.4-0.8% chance of being finalists; no or tiny chance of Top 4; no chance of being Minor Premier

  8. West Coast, Richmond, and North Melbourne: no chance of being finalists, Top 4, or Minor Premier

LADDER FINISHES

The ladder projections using the Heretical outputs appear below.

There were quite a number of large movements in teams’ Final chances this week, the biggest being:

  • Geelong +16% points

  • Fremantle +12% points

  • Gold Coast +11% points

  • Hawthorn +10% points

  • Essendon -20% points

  • GWS -18% points

  • Collingwood -14% points

There are still 9 teams with a 45% or better chance of playing Finals (and four more with a 32% or better shot), and six teams with a near 20% 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

Overall uncertainty fell only minimally this week, with the 9 least certain teams now effectively fighting for between about 10 and 11.6 ladder positions, and the 9 least certain ladder positions having 9.9 to 11.1 teams effectively fighting for them.

On the teams side, the largest exceptions are Sydney, North Melbourne, West Coast, Carlton, Richmond, St Kilda, and Adelaide, each of whom is fighting for no more than about 3 spots. On the ladder positions side, the largest exceptions are 1st, 2nd, and 15th to 18th, each of which has effectively fewer than 3 suitors.

The ladder positions with the most uncertainty remain those in the middle of the table, from about 5th to 13th.

We also see that the average team is still effectively competing for about 7.2 positions, and the average ladder position has about 7.1 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: 13% had 12 wins (down 3% points), 54% had 13 wins (up 4% points), and 14.5% had 12.5 wins (also, none had 11 wins, and 12% had 13.5 wins).

  • For teams finishing 4th in a replicate: 35% had 15 wins (up 2.5% points), 5.5% had 16 wins (up 0.5% point), and 17.5% had 15.5 wins (also, 15.5% had 14 wins, and 23% had 14.5 wins).

Looked at another way:

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

  • For teams finishing win 12 wins: 9% made Finals (down 3% points)

  • For teams finishing win 13 wins: 70% made Finals (dowb 4.5% points)

  • For teams finishing win 14 wins: 99.5% made Finals and 13% finished Top 4 (down 3.5% points)

  • For teams finishing win 15 wins: 75.5% finished Top 4 (down 1% point)

  • For teams finishing win 16 wins: 99% finished Top 4 (down 0.5% points)

Those probabilities vary by team, of course. Let’s have another look at them.

Amongst outcomes that are reasonably likely, the main conclusions here are that Essendon will likelt need 13.5 wins to play Finals, whilst the Western Bulldogs, GWS, Gold Coast, Geelong, Fremantle, Collingwood, Carlton, and Brisbane Lions can probably get in with 13 wins.

One key takeaway from this chart is that 15 wins are required for most teams to be better than 50% chances of finishing Top 4.

Here’s what it looks like on a team-by-team basis for all 18 ladder positions.

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 4-in-9 chance that 8th will be decided on percentages (it’s up by about 2% points on last week)

  • There’s now only about a 3-in-10 chance that 4th will be decided on percentages (down by about 5% points on last week)

  • There’s now about a 1-in-10 chance that 1st will be decided on percentages (up by about 3% points on last week)

FINALS CHANCES

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

A quick look at the AFL Futures markets would suggest that there might be a bit of value

IN THE MAKE FINALS MARKET ON

Dees (and much less so on the Lions and Dockers)

IN THE MISS FINALS MARKET ON

Giants and Pies

IN THE FLAG MARKET ON

Dockers, Dogs, and Dees (and less so on the Lions and Suns).

A continued reminder that I do not bet on these Futures markets.