Matter of Stats

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2022 - Team Ratings After Round 20

Geelong, despite losing Rating Points on MoSSBODS for the second week running and essential remaining static on MoSHBODS, retained top spot on both Systems this week, while Melbourne leap-frogged Sydney to take second.

In total, there were 12 moves on MoSSBODS and the same number on MoSHBODS, leaving the two Systems agreeing about the ranking of the 1st to 6th, 8th, and 13th through 18th teams. There is now only one team where they differ in their rankings by more than two places: Carlton.

Eleven teams are rated as above-average on MoSSBODS and twelve, with Essendon just making the cut, on MoSHBODS,

There were five multiple-spot movers on MoSSBODS this week, including Western Bulldogs, Richmond, and Adelaide all up 2 spots, Fremantle down 2 spots, and Carlton down 3 spots. There were also five multiple-spot movers on MoSHBODS, including Port Adelaide up 3 spots, Collingwood and Adelaide both up 2 spots, and Carlton and Fremantle both down 3 spots.

The correlation between MoSSBODS and MoSHBODS Combined Ratings remains very high, and now stands at +0.9963. The correlation on defence alone is +0.994 and on offence alone +0.992.

To provide some historical context to the teams’ current Ratings, the chart below shows the Ratings of selected teams from V/AFL history after 20 rounds of their respective seasons. Bear in mind that any season with fewer than 20 home-and-away rounds will have no teams in this chart.

Geelong, Sydney, and Melbourne are now the only teams rated higher at this point in the season than 50% of the teams in history that subsequently made the Grand Final, Melbourne having just rejoined that group, while North Melbourne and West Coast continue to record some of the lowest-ever offensive ratings.

The animation below maps the path that each 2022 team has followed to reach its current Rating.

Or, if you prefer a static view of the teams’ combined MoSSBODS Ratings, here’s an updated version of that chart

And here’s the updated MoSHBODS version.

What I think both of those charts make obvious is how the teams are broadly split into a Top 3, a Middle 13, and a Bottom 2, with the Middle 13 maybe split into nine teams and four teams.

On the Component Ratings, on offence, we find MoSSBODS and MoSHBODS now both with a Top 3 of Swans, Cats, and Lions. On defence, we find both with a Top 3 of Cats, Dees, and Dockers.

On MoSSBODS, only 5 teams are now rated positively on offence and defence (down 2), 5 are rated negatively on both (no change), two are rated positively on offence but negatively on defence (no change), and 6 are rated negatively on offence but positively on defence (up 2). The correlation between the teams’ MoSSBODS offensive and defensive Ratings now stands at just +0.65.

And, finally, to MARS, which re-ranked just six teams this week, and none by more than a single spot, swapping Sydney for Brisbane Lions in 3rd, Richmond for Fremantle in 7th, and Essendon for Gold Coast in 12th.

MARS is now most different in its thinking compared to the MoS twins about only Adelaide, which it ranks 16th compared to the twins’ ranking of 13th. For every other team, MARS’ ranking is no more than two spots different to at least one of the twins’.

In terms of groupings, we now have, according to MARS, roughly:

  • Geelong, Melbourne, Sydney, and Brisbane Lions (1,026 to 1,034)

  • Western Bulldogs, Port Adelaide, Richmond, Fremantle, and Carlton (1,004 to 1,015)

  • Collingwood, St Kilda, Essendon, and Gold Coast (994 to 1,001)

  • Hawthorn, GWS, and Adelaide (978 to 987)

  • West Coast and North Melbourne (941 to 953)

Ten teams are rated as better-than-average by MARS, with St Kilda rated just under than mark at 999.8.

The Rating gap between first and last currently stands at about 93 Rating Points, which is up about 4 Rating Points on last week.

Looking across the rankings of all three Systems and ordering the teams based on the current competition ladder, we still find relatively large differences for Collingwood where the team’s ladder position is well above its System Ranking, and for Western Bulldogs and Port Adelaide where the teams’ ladder positions are well below their System Rankings.

MARS currently has the outright most-extreme ranking for eight of the teams, MoSSBODS for five, and MoSHBODS for just one.

MoSSBODS and MoSHBODS agree about the ranking of 13 teams, MoSHBODS and MARS about nine teams, and MoSSBODS and MARS about six teams.

The magnitude of the differences remains small.

In fact, if we consider the range of rankings that the three Systems have attached to each team, we find that Adelaide and Carlton (3 spots) have the widest range of rankings, and that the range is just two spots or less for 16 teams.

The three Systems now have the same ranking for Geelong, North Melbourne, Melbourne, Port Adelaide, Sydney and West Coast.

I think it’s fair to say that the three Systems appear to be converging to mostly similar opinions.