Matter of Stats

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2023 - Team Ratings After Round 20

There were some big moves on both Systems towards the top this week, which left the Lions in 1st on MoSSBODS but now ahead of the Dees and the Pies, and saw the Pies grab 1st on MoSHBODS, ahead of the Lions and the Dees.

In total, nine teams changed places on MoSSBODS, six of them by more than two spots, and nine changed places on MoSHBODS, five of them by more than two spots. Some of the bigger moves were Melbourne and Collingwood up by 3 spots, and Port Adelaide, Geelong, and Richmond down by 3 spots on MoSSBODS, and Melbourne and Adelaide up by 3 spots, Geelong down by 3 spots, and Port Adelaide down by 5 spots on MoSHBODS. Those are some large movements for this late in the season.

The correlation between MoSSBODS and MoSHBODS Combined Ratings now stands at +0.9945 and, roughly speaking, each team’s Combined MoSHBODS Rating is about 3.65 times its Combined MoSSBODS Rating.

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

MoSSBODS now has only nine teams rated as above average on offence, the same number as does MoSHBODS. MoSSBODS now has only 12 teams rated as above average on defence, as does MoSHBODS.

To put the latest MoSSBODS Ratings in some historical context, here are the Ratings of all teams after Round 20 of their respective home-and-away seasons across V/AFL history (noting that, in some seasons, there would not have been 20 home-and-away rounds)

As an indicator of how close this season is, no team currently has a Combined Rating in the top 50% of teams that eventually went on to make the Grand Final, and only eight teams that are Rated outside the bottom decile for teams that eventually made the Grand Final. St Kilda, should they make the Grand Final, would do so as the lowest-rated team after Round 20 ever to do so.

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

On MoSSBODS, 8 teams are now rated positively on offence and defence (down 1), 4 are rated negatively on both (no change), 2 are rated positively on offence but negatively on defence (up 1), and 4 are rated negatively on offence but positively on defence (no change).

The correlation between the teams’ MoSSBODS offensive and defensive Ratings now stands at +0.75, which is up a little this week.

And, finally, to MARS, which re-ranked eight teams this week, but only the Lions by more than a single spot.

It now has the Pies in 1st, Cats in 2nd, and Dees in 3rd.

Collingwood’s lead over the Cats is just 1.8 Rating Points, and Cats over the Dees just 0.4 Rating Points.

There are still 11 teams rated better-than-average by MARS and then something of a gap back to St Kilda on 997.7.

The Rating gap between first and last now stands at about 96 Rating Points, which is down by about 4 Points on last week, while that between first and eighth now stands at under 19 Rating Points. The gap between first and fourth is only just over 3 Rating Points.

At the same point last year:

  • The gap between 1st and 18th was just under 93 Rating Points

  • The gap between 1st and 8th was just over 26 Rating Points

  • The gap between 1st and 4th was just under 8 Rating Points

Looking across the rankings of all three Systems and ordering the teams based on the current competition ladder, we find relatively large differences between the teams’ ladder positions and their rating system ordering for:

HIGHER ON LADDER THAN ON RANKING SYSTEMS: St Kilda and GWS

LOWER ON LADDER THAN ON RANKING SYSTEMS: Geelong (to some degree)

MARS this week provides the most outlying rankings at nine, ahead of MoSSBODS on eight, and MoSHBODS on three.

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

Looking finally at the range of rankings that the three Systems have attached to each team we find that Geelong and Port Adelaide (4 spots) now have the widest range of rankings, and that there are now five teams for whom the rankings span a range of more than two spots.

There are also three teams that the Systems unanimously rank the same way: Hawthorn, North Melbourne, and West Coast.