Matter of Stats

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2022 : Simulating the Final Ladder After Round 16

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

  1. Melbourne: virtually assured of a Top 8 finish, 85% chances for Top 4, and 40% chances for the Minor Premiership

  2. Brisbane Lions and Geelong: virtually assured of a Top 8 finish, 70-80% chances for Top 4, and around 15-30% chances for the Minor Premiership

  3. Fremantle: virtually assured of a Top 8 finish, 50% chances for Top 4, and around 7-8% chances for the Minor Premiership

  4. Collingwood, Carlton, Sydney, and Richmond: 65-85% chance of playing Finals, 15-35% chance of a Top 4 finish, longshots for the Minor Premiership

  5. St Kilda and Western Bulldogs: 40-45% chance of playing Finals, 5-6% chance of a Top 4 finish, extreme longshots for Minor Premiership

  6. Gold Coast and Port Adelaide: 10-25% chance of playing Finals, extreme longshots for a Top 4 finish

  7. Adelaide, Hawthorn, GWS, and Essendon: ultra extreme longshots to play Finals

  8. West Coast: very likely to finish 17th

  9. North Melbourne: very likely to claim the Spoon

(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 2.4 to 15.9, which has grown again a little from last week’s range of 2.8 to 15.6. We also see that 11 teams are still expected to finish with a win percentage above 50%.

The biggest declines in Expected Win tally came this week for Carlton and Sydney (-0.7), while the biggest increase came for Brisbane Lions and Essendon (+0.7).

In terms of Top 8 chances, there were four double-digit changes in estimate, including Collingwood’s +16% points, St Kilda’s +13% points, Western Bulldogs’ -11% points, and Carlton’s -10% points.

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

  • A larger range of Expected Wins from the Heretical approach (1.8 to 16.1 wins)

  • A similar ordering of the teams in terms of Expected Wins with only Brisbane Lions and Geelong, and Carlton and Sydney swapped

  • 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

A large reduction in average uncertainty this week, with St Kilda and Essendon the only teams registering anything more than a fractional increase in uncertainty and many registering significant decreases.

Both methods suggest that teams are, on average, effectively competing for about 6 different ladder positions, and both have most teams competing for between 4 and 9 or 10 positions, the exceptions being Essendon, West Coast, and North Melbourne.

standard methodology

heretical methodology

These tables also imply a more substantial reduction in uncertainty this week, and suggest that there are now 8 or 9 teams effectively competing for each position 4 through 9 on the ladder.

They also have the average ladder position with effectively around 6 teams likely to fill it, and with most ladder positions effectively expecting anywhere between 4 and 10 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.

It’s still the case that 13 wins (58% of replicates) is considerably more likely than 12 wins (31% of replicates) to be associated with the team that finishes 8th. For the team finishing 4th, 15 wins (53% of replicates) is once again ahead of 14 wins (37% of replicates).

This, of course, varies 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.

We see that teams are less than about 2% chances of playing Finals under either methodology with only 11 wins, and 10 to 30% chances of playing Finals with exactly 12 wins under either methodology. With 13 wins, a team is a 75-90% chance of playing Finals under the Standard Methodology, and a 65-90% chance under the Heretical Methodology.

Repeating the analysis for finishing in the Top 4.

Here we find, again, somewhat different estimates depending on the methodology we choose. Under the Standard Methodology, 13 wins is associated with a less than 1% chance of a Top 4 finish, 14 wins with 10 to 50% chances, and 15 wins with 70 to almost 100% chances.

(Note that there is still a better than even chance that 4th spot will be decided on percentages, so there will be a number of replicates where a team finishes tied in 4th on 14 wins but misses out on percentage)

Under the Heretical Methodology, more wins are associated with higher-finishing teams, and the equivalent percentage ranges are 0 to 1% for 13 wins, 3 to 40% for 14 wins, and 55 to 95% for 15 wins.

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.

The simulations are suggesting there is a slightly worse than even-money chance that 8th and 9th on the final home and away ladder will be separated only on the basis of percentage, and about a 9-in-20 chance that 8th and 10th will also only be separated on that basis.

There is also a slightly better than even-money chance that 4th and 5th will be decided on percentages, and about a 1-in-3 chance that this will be how the Minor Premiership is decided.

IMPACT OF NEXT 5 GAMES ON TEAMS’ FINALS CHANCES

Finally, we’ll again investigate, using both the Standard (top chart) and the Heretical (bottom chart) methodology simulations, what each team’s estimated chances of playing Finals will be in five games’ time, depending on how many of those five games that team ends up winning.

We see that most teams’ chances of playing Finals still increase only if they win at least 3 of their next 5 games, the exceptions being Adelaide, Essendon, GWS, Hawthorn, North Melbourne, and West Coast whose chances would only remain roughly the same with 3 wins. Gold Coast, and Port Adelaide see their chances decline a little with only 3 wins under both methodologies, as do Sydney’s and Western Bulldogs’ under the Heretical methodology.