2021 : Simulating the Final Ladder After Round 13
/In the latest Standard Method simulations, we are up to 11 teams that have a better than 1-in-5 shot at playing Finals, and eight that have a 2-in-3 or better shot. There are also five teams that have a better than 1-in-3 shot at the Top 4.
Under the Heretical Methodology, there are also 11 teams that have a better than 1-in-5 shot at playing Finals, but just seven that have a 2-in-3 or better shot (with Sydney just missing out). There are also five teams that have a better than 1-in-3 shot at the Top 4.
(For details about the methodologies I’ve used, see this earlier blog. Note that I have assumed no change in fixturing for the remainder of the season except for switching the future Swans v Saints game to be a home game for the Saints)
LADDER FINISHES
Team Expected Wins under the Standard Methodology grew by 1.0 wins this week for Collingwood, and fell by the same amount for Sydney, and by 0.9 wins for Melbourne.
The only double-digit moves in terms of Finals chances were West Coast’s increase by 13% points to 74%, and Sydney’s decrease by 16% points to 68%. Geelong saw their Top 4 chances increase by 22% points to 68%, while Sydney saw theirs fall by 14% points to 9%, and Port Adelaide saw theirs fall by 12% to 37%.
Also, according to both the Standard and the Heretical Methodology, the Dogs are around 60% chances for the Minor Premiership now, and the Dees are around 25-30% chances.
STANDARD METHODOLOGY
HERETICAL METHODOLOGY
The range of Expected Wins using the Standard Methodology across the 18 teams moved to about 12.5 wins this week, while using the Heretical Methodology it came in at 14.2 wins.
The animation below shows how each team’s ladder probabilities have varied across the season so far.
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 a 99.5% chance at least one of them will end up playing Finals.
Across the 50,000 simulations there are 30,899 different sets of teams playing Finals, treating different orderings of the same eight teams as a different set. No ordering appears in more than 42 replicates. If we ignore ordering, there are 632 different sets of eight Finalists (which is actually up a fraction on last week).
Amongst the teams currently in the Top 8, the estimated probability that any 4 through 8 of them play Finals is:
All 8: 23%
Only 7: 56%
Only 6: 19%
Only 5: 1.5%
Only 4: 0.02%
Put another way, there’s about a 77% estimated chance that the teams playing Finals won’t be the current Top 8 teams.
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 a reduction of over one full spot in final ladder position uncertainty this week only for Geelong, and increases of over one full spot for Collingwood, Adelaide, and Melbourne.
GWS, Essendon, Fremantle, and Carlton, remain the teams with greatest uncertainty about the positions in which they’ll finish on the ladder, each of them effectively competing now for about 10 ladder spots. North Melbourne, Western Bulldogs, Hawthorn, and Melbourne have least uncertainty, and are all effectively competing for only about 1.5 to 4 spots.
Geelong and Brisbane Lions are next most-certain, both effectively competing for about 6 ladder positions.
It’s interesting to note that, even after 13 rounds, the average team is still effectively competing for about 7 different ladder positions.
Last week saw increases in the uncertainty associated with all but five ladder positions, with the largest increases for 11th, 12th, 16th, and 17th, and the largest decrease for 3rd.
Positions 5th through 14th are the ones that are associated with most uncertainty, and some of the top and tail positions - 1st through 3rd, and 17th and 18th - with least uncertainty.
There are now, effectively, only about 2.5 teams vying for the Minor Premiership, and just 1.5 battling for the Spoon.
IMPORTANCE OF PERCENTAGE
After the GWS draw, the Standard Methodology simulations now suggest that it’s considerably less likely this week than it was last week that 8th place will be determined by percentage.
There is now an estimated 39% chance that 8th and 9th will finish equal on competition points (which is down about 5% points), a 13% chance that 8th and 10th will, and a 3% chance that 8th and 11th will.
There’s also about a 37% chance that the double-chance in the Finals will be determined by percentage.
WINS TO MAKE The 8 AND THE 4
Based on the Standard Methodology, the estimates of team chances of playing Finals should they finish on only 11 wins now mostly lie in the 25% to 40% range, although they are a little higher for the Lions, and a little lower for Fremantle, GWS, Adelaide, St Kilda, and Hawthorn. Team chances still also mostly lie in the 75% to 90% range should a team record 12 wins, although they are a little lower for Fremantle, St Kilda and Adelaide.
Looking next at making the Top 4, we see that teams’ chances range from about 30% to 70% with 14 wins, and 80% to 95% with 15 wins, with the Lions and Dogs faring best, and Sydney and West Coast faring worst.
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’s still the case that 12 wins rather than 11 is more likely to be associated with the team finishing 8th, and that 14 wins rather than 13 or 15 wins will be associated with 4th spot on the final home-and-away ladder, but 15 wins remains almost as likely as 14 wins for the team finishing 4th.
GAME IMPORTANCE
Finally, let’s take a look at how the Standard Methodology estimates the importance of each of the remaining 93 games (see this blog for details about how these are calculated).
This week, though, I’m going to present the importance information a little differently by showing the 10 most important games for each team (except North Melbourne, for whom no game can budge their finals chances from 0)
The way to interpret these results is as follows.
Consider the 2.60% figure in the Adelaide block for the R17 Essendon v Adelaide game. That figure is equal to:
The absolute change in Adelaide’s Final’s chances relative to their unconditional chances across all simulations if they win x the probability that they win PLUS
The absolute change in Adelaide’s Final’s chances relative to their unconditional chances across all simulations if they draw x the probability that they draw PLUS
The absolute change in Adelaide’s Final’s chances relative to their unconditional chances across all simulations if they lose x the probability that they lose
In other words, we can think of it as the expected change in Adelaide’s estimated Finals chances, relative to their unconditional chances, attributable to that Round 17 game.
So, in that sense, that Round 17 game is the most important for Adelaide.
Looking across the teams you can see that, as you might expect, individual games are of less importance for those teams with little chance of making the Finals and for those teams already almost certain to play Finals. Conversely, teams currently on the edge of the eight have a bunch of games of high importance.
In the round coming up, we see that the GWS v Carlton game is Top 10 for both teams, but likely more important for GWS than for Carlton, because the Giants are more likely to be in contention for a Finals spot. The Hawthorn v Essendon game is also meaningfully important for Essendon, as is the Gold Coast v Port Adelaide game for both teams, but more so for Port Adelaide.
