Matter of Stats

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Simulating the Finalists and Finals for 2016 After Round 21

A loss by GWS and a lacklustre performance by Geelong saw both teams' chances of the Minor Premiership decline significantly this weekend, in GWS' case into near non-existence.

Hawthorn are now assessed by MoSSBODS as favourites for the Minor Premiership, Sydney as 2nd-favourites and Adelaide as 3rd-favourites. The TAB has the same ordering.

The competition's ultimate Top 4 is now all but determined, GWS (20%) the only team from outside the current Top 4 with any realistic hope of breaking into it, though the Dogs do also have an outside chance (5%).

Likewise, the Finalists are almost locked-in. The teams currently occupying the Top 7 places on the ladder are all assured of playing Finals football, while the final spot will be the Roos' 95% of the time and the Dees' the other 5%.

For the Spoon, it's now 85% the Dons' and 15% the Lions'.

One of the curious aspects of the summary table above is that Hawthorn, despite being the team with the highest value for expected number of wins (17.3), are ranked only third in terms of expected ladder finish, behind both Sydney and Adelaide.

That's because of the still-unusual profile of its projected ladder finishes, which sees it most likely to finish 1st, but more likely to finish 3rd or 4th than 2nd.

In fact, Hawthorn has a spread of six ladder positions which it has at least a 1-in-30 chance of occupying at the end of the home-and-away season. Only one another team can say that about as many as five ladder positions (Geelong), and no other team about more than four.

Comparing the simulation results to the prices currently on offer at the TAB reveals that no team currently represents value in the Minor Premiership, Top 4 or Final 8 markets.

TOP 2s, 4s AND SO ON

The latest simulation replicates for the Top 2 ladder positions show an interesting lack of symmetry, reflecting the relative unlikelihood of a 2nd-place finish for Hawthorn.

While a Hawthorn/Sydney 1-2 finish is about a 25% possibility, a Sydney/Hawthorn finish is only a 2% possibility. Similarly, though a Hawthorn/Adelaide finish is assessed as having about a 17% probability, an Adelaide/Hawthorn finish is rated only about one-fifth as likely.

Ignoring order then, a Sydney/Adelaide 1-2 finish is the most likely, that pairing occurring in one order or the other in about 30% of replicates.

We see something similar when we expand our view to consider the Top 4. In none of the 10 most-likely orderings does Hawthorn finish 2nd. It does, however, finish 1st in five of the orderings, 3rd in three, and 4th in the remaining two.

The most-common ordering, which appeared in about 1 replicate in 6, was Hawthorn/Sydney/Adelaide/Geelong and was one of only two orderings with an estimated probability of more than 10%.

The same four teams appear in all but one of the Top 10 orderings, the exception being the 9th ordering on the list in which GWS sneaks into 4th, ousting Geelong. That ordering has only a 3% probability of occurring however.

Next we look at the bottom half of the Top 8 where we find that two orderings account for over 60% of replicates. In the first and slightly more common we have the ordering Dogs/Giants/Eagles/Roos and in the second the Dogs and Giants swap places.

Some of the less-common orderings see the Hawks, Crows or Cats slip into 5th (or even 6th, in one case, for the Hawks), GWS fall as low as 7th, and the Dees sneak into the bottom of the 8. The Roos, though, never climb higher than 8th if they make it at all.

We can also look at the most likely orderings for the entirety of the Top 8, the most likely of which now carries about a 7.5% probability and sees the Western Bulldogs climbing into 5th from their current ladder position of 7th, pushing the Giants and Eagles down one place each. All of the other teams from the current Top 8 - those in positions 1st to 4th, and 8th - remain as they are on the current competition ladder.

Interestingly, in none of the 10 most-likely orderings do the Dogs wind up occupying the spot they currently hold on the ladder (viz 7th).

SIMULATIONS FOR THE FINALS

On then to considerations of September (and October) football where we find that the simulations now rate Adelaide as 45% chances for the Flag (up 6%), Sydney as 18% chances (up 2%), Geelong as 17% (down 1%), Hawthorn as 12% chances (up 1%), GWS as 4% chances (down 8%), and the Western Bulldogs as 3% chances (no change).

At $4.50, that makes Adelaide the only attractively-priced team on the TAB Flag market. Very clearly, MoSSBODS continues to rate the Crows much more highly than does the TAB.

Whilst Adelaide are seen as being most likely to take the Flag, Sydney. Hawthorn and Geelong are assessed as being most likely to bow out in Preliminary Finala, GWS and the Western Bulldogs in Semi-Finala, and West Coast and the Kangaroos (and St Kilda and Melbourne, should they make it) in Elimination Finals.

Also, Adelaide are estimated as 70% chances of making the Grand Final, Sydney as 46%, Geelong as 34%, Hawthorn as 28%, GWS as 12%, the Western Bulldogs as 7%, West Coast and the Kangaroos as 1% each.

We can see how each team is projected to fare conditioned on its home-and-away season finish in the chart below.

That same data can be represented in tabular form and including estimated probabilities for each team conditioned on its ladder finish. This view reveals that, for any given final ladder position, the simulations have Adelaide as the team with the highest probability of winning the Flag.

The Crows aside however, it's interesting to note that Geelong generally fares better than Sydney when it finishes in the Top 4, but worse when it misses the Top 4. The Cats' overall probability for the Flag is lower than the Swans' because the Cats are assessed as being more likely to miss the Top 4.

Finally, if we analyse the simulation to see who meets in the Grand Final we find that an Adelaide v Sydney Grand Final is considered most likely, that pairing arising in almost 28% of replicates. The two next-most common quinellas also involve the Crows.

Across the 100,000 simulations, 33 different pairings appeared at least once, though only 12 appeared in more than 1 replicate in 100.

The most unlikely pairing that appeared at least once saw the Western Bulldogs facing Melbourne in the Grand Final. That pairing appeared only twice.

Amongst the most-likely Grand Final pairings, a Sydney v Western Bulldogs game is assessed as being the most competitive with Sydney starting as just 52.5% favourites, and an Adelaide v GWS matchup as the least competitive, with Adelaide overwhelming 72% favourites in such a contest.

Given the probabilities shown here, the only pairings offering value at the TAB are:

  • Adelaide/Sydney at $4
  • Adelaide/Geelong at $8
  • Adelaide/Western Bulldogs at $34 

It's clear that MoSSBODS is seeing a lot in the Crows' performances that isn't currently being reflected in prices or popular opinions. Just how perceptive or deluded that opinion proves to be will be a fascinating story for me across the remainder of the season.