Matter of Stats

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2021 - Team Ratings After Round 23

The Dees, in the end, did more than enough against the Cats, and remain in top spot on both Systems, now 1.3 Scoring Shots ahead of Brisbane Lions on MoSSBODS, and 4.6 Points ahead of them on MoSHBODS.

The two Systems now agree about the Top 11 and Bottom 3 teams.

The correlation between MoSSBODS’ and MoSHBODS’ Combined Ratings now stands at +0.9964, while the Rating gap between 1st and 8th has narrowed slightly to 5.3 Scoring Shots on MoSSBODS and to 18.3 Points on MoSHBODS. Nine teams are rated as above-average on MoSSBODS as are the same nine teams on MoSHBODS.

On the Component Ratings, on Offence MoSSBODS and MoSHBODS now have Top 3s of Lions, Dees, and Dogs, while on Defence their shared Top 3s are now Dees, Cats, and Power. MoSSBODS and MoSHBODS now have the same seven teams rated as above-average on offence, and the same 12 teams rated as above-average on defence.

On MoSSBODS, 7 teams are now rated positively on offence and defence (no change), 6 are rated negatively on both (no change), none are rated positively on offence but negatively on defence (no change), and 5 are rated negatively on offence but positively on defence (no change). The correlation between the teams’ MoSSBODS offensive and defensive Ratings now stands at +0.71, which is down a little on last week’s number.

In the animation below, we can see the path that each team has taken to arrive at its current Rating.

And, in the chart below, we can see how the current crop of teams compares with the Premiers and Runners Up across V/AFL history at the same point in their respective home-and-away seasons. Especially this week, bear in mind that we’ve lost any teams whose home-and-away season didn’t extend as far as 23 rounds.

We can see from this chart that no team now has a Combined Ratings that puts them above the median for all previous Grand Finalists at this point in their respective seasons, and that only Melbourne, Brisbane Lions, Western Bulldogs, Port Adelaide, and Geelong have Ratings that put them above the bottom 10%.

Lastly, to MARS, where we find that the Lions have widened the gap to the Cats in 2nd, and now lead by about 5.5 Rating Points.

The only changes in position were recorded by teams in the bottom third of the order, the most significant of which was Fremantle’s fall of two spots into 15th.

With St Kilda grabbing over 4 Rating Points from Fremantle, MARS now has ten teams rated as better-than-average, but only one more now rated above 990.

The Rating gap between first and last now stands at over 70 Rating Points, and that between 1st and 8th at just under 33 Rating Points. 1st and 3rd are separated by only 8.5 Rating Points, however, and 7th and 10th by only just over 5 Rating Points.

The biggest gaps in the Ratings are between 15th and 16th (9.2 Rating Points), 11th and 12th (9.1 Rating points), 6th and 7th (8.1 Rating Points), and 10th and 11th (7.8 Rating Points).

Looking across the rankings of all three Systems and ordering the teams based on the current competition ladder, we find the highest difference for West Coast, where Rating System rankings are relatively lower than Ladder position, and for Collingwood where Rating System rankings are relatively higher than Ladder position.

MARS continues to provide the most outlying rankings of the three Systems, it having the outright most extreme ranking for 10 teams now.

By comparison, MoSSBODS has the outright most extreme ranking for only three teams, and MoSHBODS for only one.

MoSSBODS and MoSHBODS agree about the ranking of 14 teams, MoSSBODS and MARS about the ranking of six teams, and MoSHBODS and MARS also about the ranking of eight teams.

Lastly, if we consider the range of rankings that the three Systems have attached to each team, we find that West Coast has the widest range of rankings (four spots), while 15 teams have rankings that differ by no more than two spots, including Adelaide, Essendon, Gold Coast, North Melbourne, Sydney, and Western Bulldogs, about whom all three Systems agree on a ranking.