Matter of Stats

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2023 - Team Ratings After Round 13

There was considerable movement at the top of both Systems’ Leaderboards this week, which ended with MoSSBODS having a Top 3 of Port Adelaide, Melbourne, and Brisbane Lions, and MoSHBODS with a Top 3 of Melbourne, Port Adelaide, and Geelong.

In total, nine teams changed places on MoSSBODS, and 11 changed places on MoSHBODS with the lone big mover on MoSSBODS being Fremantle, down three spots into 13th. On MoSHBODS there was carnage, and we had Adelaide up six spots, Port Adelaide and Richmond up three spots, Brisbane Lions, Collingwood and Sydney all down three spots, and Carlton and Fremantle down four spots.

The correlation between MoSSBODS and MoSHBODS Combined Ratings now stands at +0.9901.

On the Component Ratings, on offence we find both Systems now with a Top 3 of Power, Cats, and Lions, while on defence MoSSBODS has a Top 3 of Dees, Saints, and Pies, while MoSHBODS has it as Dees, Pies, and Saints.

MoSSBODS still has only seven team rated as above average on offence, while MoSHBODS still has 11. As well, MoSSBODS still has 12 teams rated as above average on defence, while MoSHBODS now has 12 as well.

To put the latest MoSSBODS Ratings in some historical context, here are the Ratings of all teams after Round 13 across V/AFL history.

Port Adelaide and Melbourne are now the only teams with a Combined Rating in the top 50% of teams that eventually went on to make the Grand Final. West Coast are now floating very near the edge of observed Rating..

We can also review the trajectory that each team has followed to arrive at its current Rating.

On MoSSBODS, 6 teams are now rated positively on offence and defence (no change), 5 are rated negatively on both (no change), 1 is rated positively on offence but negatively on defence (no change), and 6 are rated negatively on offence but positively on defence (no change).

The correlation between the teams’ MoSSBODS offensive and defensive Ratings now stands at +0.74, which is up on last week.

And, finally, to MARS, which re-ranked 10 teams this week, though none from the Top 3 or Bottom 5.

The only multiple spot movers were Richmond and St Kilda, who both climbed two places, and Sydney and Gold Coast who both fell two places.

There are now 13 teams rated better-than-average by MARS, a phenomenon rendered possible mostly by the extremely low Ratings of North Melbourne and West Coast..

Speaking of which, the Rating gap between first and last now stands at about 86 Rating Points, which is up by about another 4 Rating Points on where it was last week. The gap between first and eighth remains at around 20 Rating Points, and that between first and fifth is only 8 Rating Points.

Looking across the rankings of all three Systems and ordering the teams based on the current competition ladder (using Match Ratio to adjust for byes), we find relatively large differences between the teams’ ladder positions and their rating system ordering for:

HIGHER ON LADDER THAN ON RANKING SYSTEMS: Essendon

LOWER ON LADDER THAN ON RANKING SYSTEMS: Geelong (and possibly Sydney)

MoSSBODS this week provides the most outlying rankings at 13, ahead of MARS on nine and MoSHBODS on three. MoSSBODS is particularly different in terms of its ranking of Carlton.

MoSHBODS and MARS now agree about the ranking of seven teams, MoSSBODS and MARS about only two teams, and MoSSBODS and MoSHBODS about only four teams. We are, again, seeing quite a divergence in the ratings of a number of teams across the Systems.

That is especially illuminated if we consider the range of rankings that the three Systems have attached to each team. There we find that Carlton (7 spots) still has the widest range of rankings, but also that there are five other teams where the rankings span a range of three to five spots.

There are now just two teams that the Systems unanimously rank the same way: North Melbourne and West Coast.