2022 : Simulating the Finals Series After Round 22

/

With just the one home and away round remaining, time for a look at the latest set of simulations for the 2022 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: just under 1-in-3 chances for the Flag and just over 1-in-2 chances to make the Grand Final

  • Sydney: about 1-in-5 chances for the Flag and about 2-in-5 chances to make the Grand Final

  • Melbourne: about 1-in-7 chances for the Flag and about 3-in-10 chances to make the Grand Final

  • Brisbane Lions, Fremantle, and Collingwood: about 1-in-13 to 1-in-10 chances for the Flag and about 1-in-5 chances to make the Grand Final

  • Richmond: about 1-in-16 chances for the Flag and 1-in-32 to make the Grand Final

  • Carlton: about 1-in-50 chances for the Flag and 1-in-20 chances to make the Grand Final

  • Western Bulldogs: about 1-in-100 chances for the Flag and 1-in-50 chances to make the Grand Final (and about 3-in-10 chances to make the Finals at all)

  • St Kilda: tiny chance of playing Finals

  • The Rest: won’t 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, Sydney, Melbourne, and Brisbane Lions (just). But note that Geelong, Sydney, and Melbourne are all more likely to make the Grand Final than to lose in a Preliminary Final

  • Lose in a Semi Final: Fremantle and Collingwood

  • Lose in an Elimination Final: Richmond 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 is still Geelong defeating Sydney. This occurs in 8.5% of replicates. The opposite result - Sydney defeating Geelong - occurred in another 6.8% of replicates. Next we have the Geelong/Melbourne pairing, which occurred in 10.7% of replicates, then Geelong/Fremantle in 8.1%, and then Sydney/Melbourne in 7.9%.

(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 improve the results for strong teams, because it introduces less variability into the ratings used for games in the more distant future. Here that benefits Geelong.

Overall, the team-by-team main differences are:

  • Geelong’s Flag chances increase from about 32% to 44%

  • Sydney’s Flag chances increase from about 20% to 21%

  • Melbourne’s Flag chances remain at about 14%

  • Brisbane Lions’ Flag chances decrease from about 10% to 8%

  • Fremantle’s Flag chances decrease from about 8% to 4.5%

  • Collingwood’s Flag chances decrease from about 7.5% to 4.5%

  • Richmond’s Flag chances decrease from about 5.5% to 4.5%

  • Carlton’s Flag chances decrease from about 2% to 1%

  • Western Bulldogs’ Flag chances decrease from about 1% to 0.5%

For completeness’ sake, here are the Grand Final matchup numbers under this alternative methodology:

The Geelong v Sydney Grand Final now turns up in 21.5% of replicates, which is about 40% more often than under the earlier methodology, and the Geelong v Melbourne pairing appears in 13.6% of replicates, which is about 30% more often.