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2022 : Simulating the Final Ladder After Round 8

This week’s Standard and Heretical Methodology simulations see the average team’s Expected Win count change by 0.6 wins, probability of making the 8 change by just under 7% points, and probability of finishing Top 4 change by just over 1% points. Those numbers are quite similar to last week’s and suggest that we’re still at a similar point in the season, at least in terms of how single rounds affect key probability estimates.

(For details about the methodologies I’ve used, see this earlier blog).

LADDER FINISHES

The ladder projections using the Standard methodology (aka “cold” sims) appear on the left, and those using the Heretical methodology (aka “hot” sims) appear on the right.

Looking first just at the Standard Methodology, we see that the range of Expected Wins now runs from 5.2 to 17.2, which has again grown a little in size from last week’s 5.5 to 16.5. We also see that still only seven teams are expected to finish with a win percentage above 50%, and that those seven teams are estimated as having at least a roughly 7-in-10 shot at playing Finals, and about a 1-in-4 or better shot at finishing Top 4. Immediately below them, there is Richmond, who are estimated as about 1-in-2 chances of playing Finals, and then five teams with estimated Finals chances of between 1-in-5 and 3-in-10.

The biggest declines in Expected Win tally came for Sydney (-1.0), while the biggest increase came for Gold Coast (+1.0).

In terms of Top 8 chances, there were seven double-digit changes in estimate, with Hawthorn’s, Sydney’s, and Collingwood’s falling by between 11 and 14% points, and Carlton’s, Richmond’s, Port Adelaide’s, and Gold Coast’s increasing by between 11 and 13% points.

Melbourne sit at almost 2-in-3 chances for the Minor Premiership, ahead of Brisbane Lions at about 1-in-6 and Fremantle at about 1-in-8.

Comparing the results for the Standard and Heretical Methodologies we find:

  • A much larger range of Expected Wins from the Heretical approach (3.3 to 18.4 wins)

  • Seven teams with roughly a 3-in-5 or greater estimated chance of playing Finals, and a roughly a 1-in-4 or greater estimated chance of finishing Top 4

  • Melbourne as almost 2-in-3 chances for the Minor Premiership, Brisbane Lions as about 1-in-7 chances, and Fremantle as about 1-in-8 chances.

  • Similar estimates for the changes in teams’ Finals chances

TEAM AND POSITION CONCENTRATION

The HHI figures for the most recent simulation replicates appear below, with those from the Standard methodology on the left, and those from the Heretical methodology on the right. (For information about the HHI, also see that previous blog linked to earlier).

Standard Methodology - 50,000 Replicates

HERETICAL METHODOLOGY - 2,500 REPLICATES

Here we now find that the two methodologies now assess most teams similarly in terms of the number of ladder positions they are effectively competing for.

Both methods suggest that teams are, on average, effectively competing for about 9 different ladder positions, and both have most teams competing for between 6 and 13 positions, the exceptions being North Melbourne, Melbourne, and West Coast.

They also have the average ladder position with effectively 9 teams likely to fill it, and with most ladder positions effectively expecting anywhere between 6 and 13 teams to be competing for them. The exceptions amongst the ladder positions are 1st, 2nd, and 17th.

It is also, as usual, the mid-table positions that are associated with most uncertainty - 8th and 9th in particular, according to both methodologies.

WINS AND LADDER POSITION

Here’s an updated view of the distribution of team wins and final ladder position, based on the Standard Methodology

If we, again, sum across all the teams, we can see how many wins are most likely for each ladder position, as shown in the chart below.

We find that 12 wins is still more likely than 11 wins to be associated with the team that finishes 8th, and 14 wins also still comfortably more likely than 13 or 15 wins to be associated with the team that finishes 4th.

This, of course, varies by team, and in the chart below we look at how likely it is that a given team plays Finals if it records a particular number of wins, and how likely that outcome is. In the first chart we use the results from the Standard Methodology, and in the second chart from the Heretical Methodology.

We see that most teams are still less than 25% chances of playing Finals under either methodology with only 11 wins, and that most are still 65 to 80% chances of playing Finals with exactly 12 wins under the Standard Methodology, and 50 to 75% chances of playing Finals with exactly 12 wins under the Heretical Methodology, which tends to allocate fewer wins to teams towards the bottom of the ladder.

LIKELY IMPORTANCE OF PERCENTAGE

Next, we’ll use the Standard simulations to again investigate the estimated likelihood that any given pair of ladder positions be determined after Round 23 based on percentage.

The simulations are still suggesting that there is slightly less than an even-money chance that 8th and 9th on the final home and away ladder will be separated only on the basis of percentage, and still a roughly 1-in-5 chance that 8th and 10th will also only be separated on that basis.

There’s also still an estimated 2-in-5 chance that 4th and 5th will be decided on percentages, but now only about a 1-in-6 chance that this will be how the Minor Premiership is decided.

IMPACT OF NEXT 5 GAMES ON TEAMS’ FINALS CHANCES

Finally, we’ll again investigate, this time using both the Standard (top chart) and the Heretical )bottom chart) methodology simulations, what each team’s estimated chances of playing Finals will be in five games’ time, depending on how many of those five games that team has won.

We see that most teams’ chances of playing Finals still increase only if they win at least 3 of their next 5 games, the exceptions being GWS, Melbourne, North Melbourne, Port Adelaide, West Coast, and Western Bulldogs whose chances would only remain roughly the same with 3 wins.