2021 : Simulating the Final Ladder After Round 4
The latest round of home-and-away simulations is highlighting just what a competitive year we seem likely to have, at least in terms of the number of teams still with reasonable chances of playing Finals.
Let’s take a look …
(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 GWS, St Kilda, and Melbourne, and fell by about 1 full win for Collingwood, West Coast, and Gold Coast.
The big gainers in terms of Finals chances were Carlton (+14% points to 44%), St Kilda (+13% points to 30%), Adelaide (+10% points to 52%), GWS (+10% points to 17%), and Melbourne (+10% points to 90%). The big losers were Collingwood (-19% points to 24%), West Coast (-16% points to 48%), Gold Coast (-11% points to 14%), and Geelong (-10% points to 55%).
After all those moves there are now 12 teams with an estimated 30% or better chance of playing Finals.
Even under the Heretical Methodology, which tends to push probability estimates closer to 0 and 1, there are 10 teams with an estimated 30% or better chance of playing Finals.
Also, according to the Standard Methodology, the Dogs, Dees, and Swans are all better than 1 in 6 chances for the Minor Premiership.
The range of Expected Wins using the Standard Methodology across the 18 teams widened to over 9 wins this week. Using the Heretical Methodology it widened even more, coming in at almost 13 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 84% chance at least one of them will end up playing Finals.
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 for Gold Coast, Melbourne and Hawthorn, and significant increases for GWS and St Kilda.
We also see moderate reductions in the uncertainty associated with most ladder positions, but moreso for 17th and 18th positions.
Carlton are now the team with greatest uncertainty about the position in which they’ll finish on the ladder, North Melbourne the least uncertainty.
As usual, the mid-table positions remain the ones that are associated with most uncertainty, and the top and tail positions with least uncertainty.
IMPORTANCE OF PERCENTAGE
With it looking like it’ll be a quite competitive season, let’s examine what the Standard Methodology simulations tell us about how likely it is that particular ladder positions will be determined by percentage.
What we see is that there’s an estimated greater than 51% chance that 6th and 7th will finish equal on competition points (and a 24% chance that 6th and 8th will). There are also greater than 50% estimates for 7th and 8th, 8th and 9th, 9th and 10th, 10th and 11th, 11th and 12th, and 12th and 13th. There’s even a 1% chance that positions 7th through 12th will all be equal on competition points.
WINS TO MAKE The 8
The nature of the schedule, and the impact of the results we’ve already seen, is such that not all teams are equally likely to play Finals if they win, say, 11 games.
In the chart below we use the Standard Methodology simulations to estimate each team’s chances of playing Finals should they finish on 11, 11.5, or 12 wins.
We see that teams’ chances with 11 wins range from North Melbourne’s low of about 10% (the estimate for it is relatively uncertain because of the few simulation replicates in which it registers exactly 11 wins) to Brisbane Lions’ and Essendon’s highs of about 30%.
With 12 wins, all teams are better than 75% chances to play Finals, although some teams are as high as 90% chances, with Essendon’s chances highest of all.
TEAM DEPENDENCIES IN FINALS CHANCES
Each team’s chances of playing Finals is conditioned, to a greater or lesser extent, on the chances of all other teams in the competition, and especially on those teams that it is scheduled to play once or twice more in the season.
In the following chart we look at the Finals chances of the nine teams estimated to have between a 25% and a 75% unconditional chance of playing Finals.
In broad terms, the longer is the arrow for a particular team, the higher is the dependency between the teams’ Finals chances. So, for example, we see that Adelaide’s chances of playing in Finals is highly dependent on whether or not Port Adelaide plays Finals. If Port Adelaide does then Adelaide are less than 50% chances of also playing Finals (denoted by the left-hand end of the arrow), but if Port Adelaide does not play Finals, then there’s a better than 60% chance that Adelaide does (denoted by the right-hand end of the arrow).
In a similar fashion, we can see that the Lions’ chances are most dependent on the Tigers’ and Dockers’ fates, that the Blues is most dependent on the Power’s, that the Dockers’ is most dependent on the Lions’ and the Eagles’, the Cats’ on the Saints’ and Tigers’, the Power’s on the Saints’, Blues’, and Crows’, the Tigers’ on the Saints’, Cats', and Lions’, the Saints’ on the Tigers’, Power’s, and Cats’, and the Eagles’ on the Dockers’ and the Crows’.
HOW MANY WINS TO FINISH WHERE
Rather than just looking at whether or not a team makes Finals, we can also use the Standard Methodology simulation results to look at the relationship between the number of wins that a team records, and where exactly it finishes on the ladder.
In this chart, darker cells reflect more likely outcomes (and very unlikely outcomes have been excluded entirely).
From this chart we can see, for example, that Adelaide generally finishes with between 10 and 14 wins, and that, as we saw earlier, 12 wins makes it much more likely than not that they’ll play Finals. If you compare Adelaide’s results for 11 wins with that for Brisbane Lions, you can also see how the Lions have a better chance of playing Finals with that many wins than do the Crows.
WINS FOR A PARTICULAR LADDER POSITION
In this final chart, we ignore teams and simply ask what is the distribution of wins associated with each ladder position, so a darker cell means that, in the Standard Methodology simulations, a particular number of wins was more often associated with that ladder position
So we see, for example, that 12 wins is most often associated with 8th spot on the ladder, but that 11 wins is also associated with that position in a significant number of simulation replicates.
Also, we see that 13 and 14 wins are most often associated with 4th spot on the final home and away ladder.
GAME IMPORTANCE
Finally, let’s take a look at how the Standard methodology estimates the importance of each of the remaining 173 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.
Geelong are now involved in eight of the 25, Brisbane Lions in seven, Richmond, Carlton and West Coast in six, Fremantle in five, and Adelaide and St Kilda in 4 each. Seven teams - GWS, Gold Coast, Melbourne, North Melbourne, Hawthorn, Sydney, and Western Bulldogs are currently not involved in any of the estimated Top 25.