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.)
With Essendon putting a large dent in their Finals hopes last weekend, we’ve now only 9 teams with a 1 in 2 or better shot at the Finals, but still five teams with (roughly) a 1 in 3 or better shot at a Top 4 finish.
The biggest losers in terms of Expected Wins this week were St Kilda (down 0.9 wins) and Essendon (down 0.8 wins), while the biggest winners were West Coast (up 0.9 wins) and Port Adelaide (up 0.8 wins).
In terms of estimated probability of making the Finals, the largest moves were:
Essendon (down 20% points)
St Kilda (down 13% points)
Hawthorn (down 10% points, making it 19% points in two weeks)
Fremantle (down 9% points)
Brisbane Lions (up 19% points)
Port Adelaide (up 18% points)
West Coast (up 13% points)
West Coast also saw a 16% point increase in its Top 4 prospects, and Fremantle a 10% point decline.
Geelong are now just under 7 in 10 chances for the minor premiership, Collingwood about 3 in 20 chances, and GWS about 1 in 8 chances.
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%.
With Melbourne’s win this week, the new loose hierarchy of teams appears to be:
For 1st: Geelong
For 2nd & 3rd: Collingwood & GWS
For 4th to 10th: West Coast, Adelaide, Brisbane Lions, Port Adelaide, Fremantle, Richmond, and Essendon (with West Coast and Essendon perhaps forming their own tranche)
For 11th to 16th: Sydney, Hawthorn, North Melbourne, St Kilda, Western Bulldogs, and Melbourne
For 17th & 18th: Carlton & Gold Coast
Below is an animation showing how each team’s profile of likely ladder finishes has evolved since the end of Round 3.
WINS REQUIRED FOR TOP 8 AND TOP 4
GWS remains the only team with a much higher than 25% chance of playing Finals given only 11 wins. West Coast, Richmond and St Kilda have significantly lower chances and, in fact, are all less than 75% chances even with 12 wins (especially St Kilda, given its poor percentage). GWS are near-certainties for a Top 8 finish with 12 wins.
GWS are also the standout team for finishing Top 4 given only 13 wins, and almost 90% chances with 14 wins. Hawthorn, by virtue of their remaining schedule and relatively healthy percentage, have about the same chance as GWS of finishing Top 4 with 14 wins, though the confidence interval around that probability estimate is wide because of the relatively small number of simulations in which the Hawks win all 9 of their remaining games.
TOP 2s AND TOP 4s
This week, again, we’ll take a quick look at what the simulations are suggesting are the most-likely combinations of teams finishing in key positions.
For Top 2s, we have the situation as shown at right, which still sees a Geelong-Collingwood 1-2 finish as, narrowly, the most likely, it now occurring in about 1 simulation in 4.
Just behind it is the Geelong-GWS finish, which arose in 24% of the simulations. After that, the estimated probabilities still fall off fairly rapidly, dropping as low as 1% for the tenth-most common pairing of Geelong and the Port Adelaide.
Across all 10 of the combinations shown here, seven different teams appear at least once: Geelong, Collingwood, GWS, Adelaide, West Coast, Port Adelaide, and the Brisbane Lions, with Port Adelaide entering that list at the expense of Fremantle. Combined, the 10 combinations represent 90% of all of the simulations.
Looking next at Top 4s, we still find a much great diversity of potential, with even the most-likely combination appearing in only just over 1 simulation in 25, that being for a Geelong-GWS-Collingwood-West Coast finish.
In the next-most likely combination, GWS and Collingwood trade 2nd and 3rd to give a Geelong-Collingwood-GWS-West Coast ordering.
Across all 10 of the combinations shown here, six different teams appear at least once: Geelong, Collingwood, GWS, Adelaide, West Coast, Brisbane Lions and Port Adelaide, with the Lions and Port new to that list, and the Dockers now missing. Combined, the 10 combinations represent only 26% of all of the simulations.
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 43% of the simulations (down 1% point), and 8th and 9th are separated by percentage in about 50% of the simulations (down 3% points). As well, 8th and 10th are separated by percentage in about 21% of the simulations, and 8th from 11th in about 7%.
In general, the likelihood that percentage will determine key positions has reduced a little this week.
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 decrease fairly substantially, with the Gini coefficients rising to around 0.61, another season high.
At the team level, we saw reductions in uncertainty for most teams, the biggest exception being Sydney, though uncertainty also increased for Geelong, Collingwood, GWS, and Melbourne.
Essendon, Richmond, Fremantle, Port Adelaide, Sydney, and Hawthorn (who fill ladder positions 7th through 10th, 12th and 14th, as the new column this week reveals) now have the most uncertainty, while Geelong, Gold Coast, Carlton, and Collingwood (who fill positions 1st through 3rd, 17th and 18th), still 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 80% to 90% chances that either of two teams will occupy them at season’s end, whilst positions 7th through 12th still have the widest range of possible tenants.
Every ladder position except 1st, 2nd and 16th, became at least a little more certain about who will occupy it come the end of the home-and-away season, with the biggest increases coming for positions 4th through 9th, and 12th.
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, all but three of the Top 30 are common to last week’s list, though there are only 81 games left in the home and away season.
In terms of the temporal distribution of these games, we now have:
Rounds 15 to 17: 8 games from 27 (30%)
Rounds 18 to 20: 11 games from 27 (41%)
Rounds 21 to 23: 11 games from 27 (41%)
We see only small changes in the level of involvement in games assessed as being important for each team this week:
9 games involving Richmond (no change)
8 games involving Port Adelaide (no change), or Fremantle (up 3)
6 games involving Essendon (down 1)
5 games involving Brisbane Lions (down 2)
3 games involving North Melbourne (no change), or Western Bulldogs (up 1)
2 games involving Adelaide (no change), Collingwood (no change), GWS (no change), Geelong (up 1), Sydney (no change), West Coast (down 1), or St Kilda (down 1)
1 game involving Carlton (no change), Gold Coast (no change), Hawthorn (no change), or Melbourne (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:
24%: Port Adelaide
20%: Brisbane Lions
11%: West Coast and Hawthorn
10%: North Melbourne
No other team has a higher than 8% estimated probability of finishing in 8th or 9th combined.