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2022 : Simulating the Final Ladder After Round 20

This will probably be the second-last time I do these simulations for the men’s competition in 2022, because home-and-away ladder simulations are generally fairly boring with just a single round to play

These latest ones - both Standard and Heretical - suggest that the teams can now be roughly grouped as follows:

  1. Geelong: assured of a Top 8 finish and almost certainly a Top 4 finish, and about 90% chances for the Minor Premiership

  2. Melbourne and Sydney: assured of a Top 8 finish, 85-90% chances for Top 4, and around 2-8% chances for the Minor Premiership (higher for Melbourne)

  3. Collingwood and Brisbane Lions: virtually assured of a Top 8 finish, 45-50% chances for Top 4, and longshots for the Minor Premiership

  4. Fremantle: virtually assured of a Top 8 finish and about 25% chances for Top 4

  5. Carlton: 80-85% chance of playing Finals and around 4-5% chance of a Top 4 finish

  6. Western Bulldogs: 50-60% chances of playing Finals

  7. St Kilda and Richmond: around 30-35% chance of playing Finals

  8. Gold Coast and Port Adelaide: longshots to play Finals

  9. Hawthorn, Essendon, Adelaide, GWS, West Coast, and North Melbourne: looking to 2023 and draft picks

(For details about the methodologies I’ve used, see this earlier blog).

LADDER FINISHES

The ladder projections using the Standard methodology (aka “cold” sims) appear on the left, and those using the Heretical methodology (aka “hot” sims) appear on the right.

Looking first just at the Standard Methodology, we see that the range of Expected Wins now runs from 2.6 to 17.4, which has grown a little from last week’s range of 2.8 to 17. We also see that only 10 teams are expected to finish with a win percentage above 50%.

The biggest declines in Expected Win tally came this week for Carlton (-0.7), while the biggest increases came for Adelaide and Melbourne (+0.7).

In terms of Top 8 chances, there were only two double-digit changes in estimate, including Richmond’s +13% points and Carlton’s -10% points.

There were also six double-digit changes in estimates of Top 4 finishes, with big gains for Melbourne, Sydney, and Collingwood, and big losses for Brisbane Lions, Fremantle, and Carlton.

Comparing the results for the Standard and Heretical Methodologies we find:

  • A slightly larger range of Expected Wins from the Heretical approach (2.5 to 17.5 wins)

  • A similar ordering of the teams in terms of Expected Wins with only Western Bulldogs and St Kilda swapping places

  • Broadly similar estimates for the changes in teams’ Finals chances

TEAM AND POSITION CONCENTRATION

The HHI figures for the most recent simulation replicates appear below, with those from the Standard methodology on the top, and those from the Heretical methodology on the bottom. (For information about the HHI, also see that previous blog linked to earlier).

STANDARD METHODOLOGY

heretical methodology

Yet another chunky - but expected with just a few rounds to go - reduction in average uncertainty this week, with decreases or insignificant increases for every team and most notably for Fremantle, Sydney, and Melbourne.

Both methods suggest that teams are, on average, effectively competing for about 3.5 different ladder positions now, and both have most teams competing for between 3 and 5 positions, the exceptions being North Melbourne, West Coast, Geelong, and GWS all of whom have now effectively got only 1 or 2 spots they could occupy on the ladder at home-and-away season’s end.

standard methodology

heretical methodology

These tables also imply a large percentage reduction in uncertainty this week, but also suggest that there are still 4 or 5 teams effectively competing for each position 3 through 10 on the ladder.

They also have the average ladder position with effectively around 3.5 teams likely to fill it, and with most ladder positions effectively expecting anywhere between 3 and 5 teams to be competing for them. The exceptions amongst the ladder positions are 1st, and 16th through 18th.

WINS AND LADDER POSITION

Here’s an updated view of the distribution of team wins and final ladder position, based on the Standard Methodology

If we, again, sum across all the teams, we can see how many wins are most likely for each ladder position, as shown in the chart below.

The draw between Richmond and Fremantle has, as noted last week, brought the scenarios with half-wins more into play and means that 12 wins is now associated with the team finishing 8th in 31% of replicates, 12.5 wins in 21% of replicates, and 13 wins in 41% of replicates.

For the team finishing 4th, 14.5 wins is now the result in 8% of replicates, 15 wins in 71%, 15.5 wins in 9%, and 16 wins in 7%.

These percentages, of course, vary by team, and in the chart below we look at how likely it is that a given team plays Finals if it records a particular number of wins, and how likely that outcome is. In the first chart we use the results from the Standard Methodology, and in the second chart from the Heretical Methodology.

Under both methodologies, Richmond and Western Bulldogs are the only teams with better than even chances of playing Finals if they finish with 12 or fewer wins. Carlton are about 40% chances, and Gold Coast and St Kilda 15-20% chances if they finish with 12 or fewer wins.

Repeating the analysis for finishing in the Top 4.

Under both methodologies, Sydney is the only team with a better than even chance of finishing Top 4 when it registers only 14.5 wins or fewer for the season. Under that same scenario, Brisbane Lions are about 40% chances, and Carlton, Collingwood, Fremantle, and Melbourne about 15-25% chances.

LIKELY IMPORTANCE OF PERCENTAGE

Next, we’ll use the Standard simulations to again investigate the estimated likelihood that any given pair of ladder positions be determined after Round 23 based on percentage.

Last week’s results slightly increased the likelihood that percentages will separate 8th and 9th on the final home and away ladder, but only to about 30%. They also reduced the likelihood that 4th and 5th will be decided on percentages (38%), and that this will be how the Minor Premiership is decided (17%).

MOST LIKELY SET OF FINALISTS AND TOP 4S

Across the 50,000 replicates from the Standard Methodology, there were 4,686 unique orderings of the 18 teams, and 20 different sets of teams comprising the Top 8.

In the table at right we show those 20 sets of 8 teams that finish as the Finalists, in some order, in at least one replicate.

Three sets of 8 stand out, as you can see, and together appear in over 80% of the replicates. The first of those comprises all of the teams from the current Top 7, but swaps in Western Bulldogs for St Kilda in 8th. The next swaps in Richmond for St Kilda in 8th, and the third includes all of the teams currently in the Top 8.

After that, no combination appears in more than 1-in-14 replicates.

There are now unique orderings of the Top 8 that appear in more than 1% of replicates, and they are shown in the table below.

Both see Western Bulldogs moving from its current 10th spot to finish 7th, relegating Carlton to 8th and pushing St Kilda out of the Finals. The first also sees Sydney moving into 3rd from 4th, Brisbane Lions into 4th from 5th, and Collingwood slipping from 3rd to 5th.

The second takes the first and swaps Melbourne and Sydney.

Note that neither of these finishes is truly “likely”.

What about the Top 4, also taking order into account.

There remains quite a lot of uncertainty about this, too, with even the most common Top 4 - which sees Sydney move from their current 4th spot into 3rd, and Brisbane Lions from 5th to 4th - occurring in only about 1-in-9 replicates. The current Top 4 in their current order is only the fourth-most likely final outcome and it appears in only about 1-in-20 replicates.

Altogether there are 25 Top 4 orderings that appeared in at least 1% of replicates, with Carlton cameoing in two, Fremantle in five (never finishing higher than 3rd), Brisbane Lions in 11, and Collingwood in 12. These 25 orderings - of which there were 249 in total across the entire simulation - together account for only 78% of all replicates.

Geelong finishes as minor premier in all but three of the orderings shown here, Melbourne appear somewhere in all but two of them, and Sydney in all but three.

Lastly, let’s look at the Top 2s that came out of the simulations.

The current Top 2 of Geelong and Melbourne dominate, that pair in one order or the other appearing in over 50% of replicates.

The second through fourth most-common orderings all have Geelong in 1st and swap in one of Sydney, Collingwood, or Brisbane Lions for 2nd. Together, they account for over over 40% of replcates.

There are then - after the Melbourne/Geelong ordering - just two more orderings that occurred in at least 1% of replicates.