2019 : Simulating the Final Ladder After Round 9
/The results of the latest 50,000 simulations appear below.
(If you’re curious about the methodology used to create them, you can start here.)
RESULTS
The gap between Expected Wins for Geelong versus Carlton continues to grow and this week stands at about 10.2 wins, up 1.0 wins on last week. Only seven teams are expected to finish the home-and-away season with a 50% or better win percentage, though even Hawthorn in 13th is expected to go about 10 and 12.
The week’s biggest losers in terms of Expected Wins, according to the simulations, were North Melbourne (1.0 Expected Wins), and Carlton (down 0.7 Expected Wins), while the biggest gainers were Sydney (up 0.8), and GWS (up 0.7).
Looking at the simulations through the lens of making the Finals, we have:
LOSERS
Hawthorn (down 12% points)
GAINERS
Richmond (up 10% points, making it 21% points in the last two weeks)
GWS and Brisbane Lions (up 8% points each)
Only eight teams, still, are currently better than even-money propositions for the Finals, but Geelong remain better than even-money chances for the minor premiership spot alone, and Collingwood remain roughly 3/1 propositions for that spot.
DETAILED LADDER FINISH ESTIMATES
The detailed view of each team’s estimated probability of finishing in each of the 18 possible ladder positions appears below. Blank cells represent ladder finishes that did not occur even once in the 50,000 simulations, while cells showing a value of 0 represent estimated probabilities below 0.05%.
WINS REQUIRED FOR TOP 8 AND TOP 4
This week we’ll look for the first time here at what the simulations reveal about the likelihood of each team playing Finals or finishing Top 4 depending on the number of wins it records.
Here, firstly, is the analysis for a Finals berth.
Only a handful of teams have better than 25% chances of playing Finals with just 11 wins, but all have about 75% or better chances with 12 wins. Due to the nature of their remaining schedules, and their current percentages, West Coast has the smallest chance of playing Finals after registering only a 12 and 12 home-and-away record, while Carlton has the highest chance (but would need to win 11 games from the remaining 13 to get there).
Next, let’s look at the analysis for Top 4.
Here we see that most teams have a 30% or lower chance of finishing Top 4 with a 13 and 9 record, but most have a 75% or higher chance with a 14 and 8 record. Brisbane Lions, West Coast, St Kilda and Richmond have the lowest chances of a Top 4 finish should they win only 14 home-and-away games.
LIKELIHOOD OF PERCENTAGE DETERMINING POSITIONS
We’ll also look for the first time this week at an analysis showing how likely it is that key positions on the final home-and-away ladder will be determined by percentage because the teams in those positions finish tied on competition points.
We see, for example, that 4th and 5th are separated by percentage in about 43% of the simulations, and that 8th and 9th are separated by percentage in about 52% of the simulations. So, in other words, at this stage it’s slightly more likely than not that the last spot in the Finals will be determined based on the percentages of the teams in contention. (There’s also about a 24% chance that 8th, 9th and 10th will all finish on the same number of competition points.)
TEAM AND POSITION CONCENTRATION
As mentioned for a few weeks now, one way of measuring how much uncertainty there is in the competition is to use the Gini measure of concentration commonly used in economics for measuring income inequality to quantify the spread of each team's estimated final ladder positions across the 50,000 simulation replicates, and to quantify the concentration in the probabilities across all the teams vying for any given ladder position.
This week saw the uncertainty about the final ordering of the teams reduced somewhat, with the Gini coefficients moving, roughly, from 0.47 to 0.51.
At the team level, we saw reductions in uncertainty for every team excapt Sydney, with the largest relative reductions for North Melbourne, Hawthorn, Richmond, Brisbane Lions, GWS, West Coast and Fremantle.
Even with the reductions, Essendon, St Kilda, Fremantle, Hawthorn, and Western Bulldogs still have the most uncertainty, while Geelong, Carlton, Collingwood, and Gold Coast still have most certainty about their eventual ladder finishes.
Those results are a consequence of the fact that Geelong, Carlton, and Collingwood are at least 70% chances to finish in any of 3 ladder positions, while Essendon, St Kilda, Fremantle, Hawthorn, and Western Bulldogs are no greater than 10.5% chances to finish in any given ladder position.
Next, if we adopt a ladder position viewpoint, we see that 1st and 18th remain the positions with the narrowest range of likely occupants at season's end, with about 80% chances that one of two or three teams will occupy them at season’s end, whilst positions 7th through 12th continue to have the widest range of possible tenants, with 10 or 11 teams all having estimated 5% or higher chances of occupying them at the end of the season.
Looking more broadly, we see that every ladder position became more certain about which team will occupy it come the end of the home-and-away season. The biggest relative increases in certainty were for positions 11th, 12th and 13th.
GAME IMPORTANCE
Here are the updated assessments of the 30 most-important games between now and the end of the home-and-away season. (See this blog for details about how these are calculated.)
This week, 24 of the Top 30 are common to last week’s list, as well as all of the Top 8, and 11 of the Top 19.
In terms of the temporal distribution of these games, we now have:
Rounds 10 to 14: 6 games from 36 (17%)
Rounds 15 to 18: 10 games from 36 (28%)
Rounds 19 to 23: 14 games from 45 (31%)
By team we have:
10 games involving Port Adelaide or Essendon
7 games involving West Coast
6 games involving Western Bulldogs
5 games involving Adelaide or Fremantle
4 games involving Hawthorn or St Kilda
2 games involving Richmond, GWS, or Brisbane Lions
1 game involving Collingwood, North Melbourne, or Gold Coast
0 games involving Geelong, Melbourne, Sydney or Carlton
We can again see the commonsense of this list when we compare it with the simulated probabilities for teams finishing in 8th or 9th, which are:
20%: Essendon
19%: Port Adelaide and West Coast
18%: Adelaide
17%: St Kilda and Brisbane Lions
16%: Western Bulldogs, Fremantle, and Hawthorn
13%: Richmond
No other team has a higher than 7% estimated probability of finishing in 8th or 9th combined.
