2019 : Simulating the Final Ladder After Round 11
/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
We’re starting to see some winnowing of the teams this week, with only 10 now with at least at 1 in 3 shot at the Finals, down two teams compared to last week, and only four teams with a 1 in 3 or better shot at a Top 4 finish.
The week’s biggest losers in terms of Expected Wins, according to the simulations, were Collingwood, who dropped 1.0 Expected Wins, and Richmond, who dropped 0.8 Expected Wins. The biggest gainers were Fremantle (+1.1 Expected Wins) and North Melbourne (+0.9 Expected Wins).
Looking at the simulations through the lens of making the Finals, we have:
BIGGEST LOSERS
St Kilda (down 16% points)
Hawthorn (down 14% points)
Richmond (down 13% points)
BIGGEST GAINERS
Fremantle (up 20% points)
Port Adelaide (up 12% points)
Geelong are now estimated to be 60% chances for the minor premiership, GWS about 1 in 5 chances, and Collingwood about 1 in 8.
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%.
The heatmap still shows relatively high levels of uncertainty about mid-table ladder positions, which we’ll return to and quantify a little later.
WINS REQUIRED FOR TOP 8 AND TOP 4
This week we’ll look again 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.
This week, only a couple of teams still have 25% or better chances of playing Finals with just 11 wins, and all but five have 75% or better chances with 12 wins. St Kilda, West Coast, and Geelong have the lowest chances of making the Top 8 with only a 12 and 10 record, and GWS still has the highest chances.
Next, let’s look at the analysis for Top 4.
Here we see that only three teams have a better than 25% chance of finishing Top 4 with a 13 and 9 record (GWS, Sydney and Melbourne), and only seven have about a 75% or higher chance with a 14 and 8 record. Brisbane Lions, West Coast, St Kilda and Richmond still have the lowest chances of a Top 4 finish should they win only 14 home-and-away games.
LIKELIHOOD OF PERCENTAGE DETERMINING POSITIONS
Next we’ll analyse 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.
This week, 4th and 5th are separated by percentage in about 44% of the simulations (up 4% points), and 8th and 9th are separated by percentage in about 51% of the simulations (down 1% point). So, it remains the case that 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.
TEAM AND POSITION CONCENTRATION
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 again, with the Gini coefficients moving, roughly, from 0.54 to 0.56.
At the team level, we saw reductions in uncertainty for every team except Collingwood, North Melbourne and Richmond, with the largest relative reductions for the Western Bulldogs and St Kilda.
Essendon, Fremantle, Port Adelaide, Hawthorn and Adelaide have the most uncertainty, while Carlton, Geelong, Gold Coast and GWS have the most certainty about their eventual ladder finishes.
Next, if we adopt a ladder position viewpoint, we see that 1st and 18th remain the positions with the narrowest range of likely occupants, with about 75% to 85% chances that either of two teams will occupy them at season’s end, whilst positions 7th through 12th have the widest range of possible tenants.
Interestingly, each of the ladder positions 1st through 4th became less certain about which team will occupy them come the end of the home-and-away season. The increased uncertainty about the minor premiership comes not because Geelong is less likely to take it (in fact, the opposite is true) but because GWS and Collingwood now have more nearly equal chances to do so. The only other position seeing a reduction in certainty was 10th, which is now the position about which we have least certainty. Ten teams have a 5% or higher chance of finishing in 10th.
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, 22 of the Top 30 are common to last week’s list, as well as 14 of the Top 15.
In terms of the temporal distribution of these games, we now have:
Rounds 12 to 15: 5 games from 27 (19%)
Rounds 16 to 19: 12 games from 36 (33%)
Rounds 20 to 23: 13 games from 36 (36%)
By team we see quite a concentration now of key games involving one or both of four teams (Fremantle, Port Adelaide, Adelaide, and Essendon):
10 games involving Fremantle (up 5)
9 games involving Port Adelaide (down 1)
8 games involving Adelaide (no change) or Essendon (up 2)
3 games involving Hawthorn (down 3), West Coast (down 1) or Western Bulldogs (down 2)
2 games involving Brisbane Lions (down 2), Collingwood (up 1), North Melbourne (no change), Richmond (no change), St Kilda (down 3), or Sydney (up 1)
1 game involving Carlton (no change), Geelong (up 1), GWS (up 1), or Melbourne (up 1)
0 games involving Gold Coast (no change)
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:
23%: Adelaide
22%: Fremantle
21%: Port Adelaide and Essendon
18%: Brisbane Lions and Hawthorn
17%: Richmond
No other team has a higher than 15% estimated probability of finishing in 8th or 9th combined.
