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2021 : Simulating the Final Ladder After Round 6

The latest round of Standard Methodology home-and-away simulations has 13 teams with a better than 1-in-5 shot at playing Finals, and 8 teams with a better than 1-in-5 shot at finishing Top 4. Even under the Heretical Methodology, which tends to push probability estimates closer to 0 and 1, there are 12 teams with a better than 1-in-5 shot at playing Finals, and 7 teams with a better than 1-in-5 shot at finishing Top 4.

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

LADDER FINISHES

Team Expected Wins under the Standard Methodology grew by about 1 full win this week for Melbourne, Geelong, Essendon, and Gold Coast, and fell by about 1 full win for Sydney and Collingwood.

The big gainers in terms of Finals chances were Geelong (+19% points to 76%), Brisbane Lions (+13% points to 65%), and Essendon (+12% points to 26%). The big losers were Sydney(-15% points to 61%), West Coast (-14% points to 38%), and Collingwood (-10% points to 11%).

Also, according to both the Standard and the Heretical Methodology, the Dogs and Dees are both about 2-in-5 chances for the Minor Premiership.

STANDARD METHODOLOGY

HERETICAL METHODOLOGY

The range of Expected Wins using the Standard Methodology across the 18 teams widened to about 10.8 wins this week. Using the Heretical Methodology it widened to about 14.4 wins.

Of the five teams that started with a 0-2 record (Brisbane Lions, Carlton, GWS, Essendon, and North Melbourne), the Standard Methodology now estimates that there’s about an 89% chance at least one of them will end up playing Finals.

Across the 50,000 simulations there are 48,979 different sets of teams playing Finals, treating different orderings of the same eight teams as a different set. No ordering appears in more than four replicates. If we ignore ordering, there are 3,712 different sets of eight Finalists.

TEAM AND POSITION CONCENTRATION

The HHI figures for the most recent Standard Methodology simulation replicates appear below.

(For information about the HHI, also see that previous blog linked to earlier).

We see considerable reductions in final ladder position uncertainty this week for Geelong and Collingwood, who are now effectively competing for 10 or 11 ladder positions, which is about three fewer than was the case last week.

West Coast are now the team with the greatest uncertainty about the position in which they’ll finish on the ladder (although seven other teams have only one to one-and-a-half fewer positions for which they are effectively competing than the Eagles). North Melbourne still have the least uncertainty, though Melbourne and Western Bulldogs also enjoy relatively low levels, with each of them effectively competing now only for about four different spots.

We also see reductions in the uncertainty associated with all ladder positions except 15th through 17th, with the largest reductions for positions 1st through 6th.

It’s still that case that the mid-table positions - 6th through 12th - are the ones that are associated with most uncertainty, and the top and tail positions - 1st through 3rd, and 16th through 18th - with least uncertainty.

There are now, effectively, only about three teams vying for the Minor Premiership, and less than two battling for the Spoon.

IMPORTANCE OF PERCENTAGE

The Standard Methodology simulations suggest that it became slightly less likely that key ladder positions will be determined by percentage, but that it’s still more likely than not that the last spot on the Finals will be so determined.

There is now an estimated 52% chance that 8th and 9th will finish equal on competition points, a 24% chance that 8th and 10th will, and a 10% chance that 8th and 11th will.

There’s also a 41% chance that the double-chance in the Finals will be determined by percentage.

WINS TO MAKE The 8

The estimates of team chances of playing Finals should they finish on 11, 11.5, or 12 wins have again not much changed this week, with most teams still enjoying about a 20% to 30% chance with 11 wins, and an 80% to 90% chance with 12 wins.

St Kilda, Adelaide, West Coast, Fremantle, and Hawthorn (and North Melbourne, where an estimate can be sensibly calculated) have the lowest estimated chances of playing Finals with either 11 or 12 wins, while Collingwood, Richmond and Brisbane Lions have the highest estimated chances.

TEAM DEPENDENCIES IN FINALS CHANCES

Next, let’s review the dependencies in the estimated Finals chances of the seven teams now estimated to have between a 25% and a 75% unconditional chance of playing Finals.

Using the arrow lengths as a proxy for dependence, we see that:

  • The Lions’ chances are most dependent on the Tigers’ and the Dockers’

  • The Blues’ are most dependent on the Swans’, Eagles’, Dons’, and Dockers’

  • The Dons’ are about equally dependent on the Eagles’, Swans’, Tigers’, Dockers’, and Blues’

  • The Dockers’ are most dependent on the Swans’, Lions’ and Eagles’

  • The Tigers’ are most dependent on the Lions’

  • The Swans’ are most dependent on the Dockers’

  • The Eagles’ chances are most dependent on the Dockers’

HOW MANY WINS TO FINISH WHERE

Now a look at what the Standard Methodology shows for the joint distribution of number of wins and final ladder position for each team.

WINS FOR A PARTICULAR LADDER POSITION

And, finally, an update on the distribution of wins associated with each ladder position.

It now looks as though 11 wins and 12 wins are about equally likely to be associated with the team finishing 8th, and that 14 wins are still more often than 13 wins associated with 4th spot.

GAME IMPORTANCE

Finally, let’s take a look at how the Standard methodology estimates the importance of each of the remaining 155 games (see this blog for details about how these are calculated).

Here is the list of the 25 most important games in terms of their estimated influence on the composition of the finalists.

Fremantle are now involved in 11 of the 25 (including this week’s clash with the Eagles), West Coast and Sydney in eight, Brisbane Lions in six, and Richmond in four. Eight teams - Essendon, Gold Coast, Melbourne, North Melbourne, Hawthorn, St Kilda, and Western Bulldogs are currently not involved in any of the estimated Top 25.