2022 : Simulating the Finals Series After Round 18
/With just five rounds to go now until the Finals, let’s take a look at the latest set of simulations for those Finals.
(For details about the methodology, see this blog post and also refer to this one from last week that talks about an alternative approach to adding time-based variability to team ratings that I’m currently trialling)
Applying the “traditional” methodology to 10,000 of the 50,000 home and away season simulation replicates yields the following chart showing teams’ Finals fate overall and as a function of their ultimate ladder position at the end of the home and away season.
Overall, we see that the teams fall fairly naturally into seven groups:
Geelong: still around 1-in-4 chances for the Flag and about 4-in-9 chances to make the Grand Final
Melbourne and Sydney: just over 1-in-6 chances for the Flag and about 1-in-3 chances to make the Grand Final
Brisbane Lions and Fremantle: about 1-in-9 chances for the Flag and just over 2-in-9 chances to make the Grand Final
Collingwood and Carlton: about 1-in-16 to 1-in-20 chances for the Flag and just under 1-in-4 chances to make the Grand Final
Richmond and Western Bulldogs: about 1-in-50 chances for the Flag and 1-in-25 chances to make the Grand Final
St Kilda, Gold Coast, and Port Adelaide: about 1-in-200 chances for the Flag and 1-in-100 chances to make the Grand Final (and from 1-in-5 to 1-in-10 chances of even making Finals)
The Rest: unlikely to make the Finals
We also can see that Geelong, Melbourne and Sydney are the only teams that win more than 50% of the Grand Finals that they make.
WEEK OF ELIMINATION IN FINALS
In this next chart we look at teams' chances for various Finals finishes, ignoring their home and away ladder positions (ie we focus solely on the heights of the bars in the previous chart). The numbers shown inside a cell are the percentage of simulation replicates (multiplied by 100) in which the specified team went out in the specified week of the Finals.
We see here that, if we define the season in terms of the five events listed above plus "Miss the Finals", the most-likely finishes for each team are estimated to be:
Lose in a Preliminary Final: Geelong, Melbourne, Sydney, and Brisbane Lions. But note that Geelong, Melbourne, and Sydney are all more likely to make the Grand Final than to lose in a Preliminary Final
Lose in a Semi Final: Fremantle
Lose in an Elimination Final: Collingwood and Carlton
Miss the Finals: all other teams
GRAND FINAL PAIRINGS
In this final chart we look at all of the Grand Final pairings that occurred in at least one of the simulation replicates. The numbers shown inside a cell are the percentage of simulation replicates (multiplied by 100) in which the team named in the row defeated the team named in the column in the Grand Final.
We see that the most common Grand Final, again, has Geelong defeating Melbourne. This occurred in 6% of replicates. The opposite result - Melbourne defeating Geelong - occurred in another 5% of replicates. A Geelong v Sydney Grand Final is the next most likely, occurring in about 10.5% of replicates. Geelong v Brisbane Lions is next at around 7%.
(Note that zeroes in the chart represent pairings that did occur at least once but in less than 0.05% of replicates.)
CHARTS FOR THE ALTERNATIVE METHOD
Applying the alternative methodology (see this post for details) to both the home and away season simulations and then to 10,000 of those for the purposes of simulating the Finals yields the following, alternative outputs.
As we’ve seen each week in the comparison, this methodology tends to improves the results for strong teams, because it introduces less variability into the ratings used for games in the more distant future.
Overall, the team-by-team main differences are:
Geelong’s Flag chances increase from about 26% to 36%
Melbourne’s Flag chances increase from about 18% to 20%
Sydney’s Flag chances increase from about 17% to 20%
Brisbane Lions’ Flag chances decrease from about 11% to 8%
Fremantle’s Flag chances decrease from about 11% to 7%
Collingwood’s Flag chances decrease from about 6.5% to 3%
Carlton’s Flag chances decrease from about 5% to 3%
Richmond ’s Flag chances decrease from about 2% to 1%
Western Bulldogs’ Flag chances decrease from about 2% to 1.5%
For completeness’ sake, here are the Grand Final matchup numbers under this alternative methodology:
The Melbourne v Geelong Grand Final now turns up in 16% of replicates, which is about half as much again as under the earlier methodology. Geelong v Sydney appears in 17% of replicates, with Melbourne v Sydney now in third at just under 10% of replicates.
