Matter of Stats

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2018 : Simulating the Finals Series After Round 21

Time to update our views on how, according to MoSHBODS, this year's finals might play out.

Firstly, let's look at the relationship between teams' ladder finishes and ultimate finals performance, applying the methodology described here to the 50,000 final ladders produced by our original simulations for this week.

Melbourne's profile took a distinct turn for the worse this week, with almost all of the orange and yellow storeys disappearing from its building stack leaving the entire complex looking more high-rise flats than city skyline. A similar fate befell Port Adelaide, which, combined with Melbourne, provided the building material mostly used by GWS and Hawthorn to add height to their orange and yellow penthouses. (Richmond has virtually tied up the entire supply of red building material.)

Sydney also added floor space, but mostly of the blue-green variety, much of which it repurposed from North Melbourne renovations.

Twelve teams, again, made the Finals in at least one of the simulation replicates this week, Adelaide now least often of all, scraping into the Finals in just 26 of the 50,000 replicates and winning the Flag in just one (defeating Richmond, as it happens).

Richmond win the Grand Final in 35% of those replicates where they make the Finals (which is all of them), West Coast in 16%, GWS in 15%, Collingwood in 12%, Hawthorn in 9%, and Melbourne in 8%.

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 (or achieved the specified result).

(Note that 0 entries reflect estimated probabilities greater than 0% but under 0.05%).

Richmond are now assessed as about 35% chances for the Flag (up 1% point on last week) and about 55% chances of playing in the Grand Final (also up about 1% point). West Coast are now about 16% chances for the Flag (up 1% point), GWS about 15% (up 2% points), and Collingwood about 12% chances (up 3% points). 

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:

  • Win the Grand Final: Richmond
  • Lose in a Preliminary Final: West Coast and GWS
  • Lose in a Semi Final: Collingwood and Hawthorn
  • Lose in an Elimination Final:  Sydney, Melbourne and Geelong
  • 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.

(Note that 0 entries reflect estimated probabilities greater than 0% but under 0.05%).

We see that the Grand Final pairing of Richmond v West Coast remains most common, and now appears in about 14% of replicates. Next still is Richmond v GWS, which appeared in roughly 13% of replicates, and then Richmond v Collingwood (10%).

The most-likely Grand Final not involving Richmond remains a West Coast v GWS one, which occurred in about 8% of replicates.