Matter of Stats

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2016 - Team Ratings After Round 22

MARS is the week's most active Rating System, altering the position of eight teams including four from last week's Top 7.

It moved only two teams though by more than a spot, GWS rising two places into 4th, and Hawthorn sliding two places into 5th. That left MARS with a Top 4 of:

  1. Sydney
  2. Adelaide
  3. West Coast
  4. GWS

ChIPS was much more circumspect, moving only four teams and those all by just a single spot.

That left ChiPS with the same Top 4 teams, but in a different order:

  1. Sydney
  2. Adelaide
  3. GWS
  4. West Coast

More broadly, the week's changes leave ChiPS and MARS differing in their rankings of all 18 teams by no more than a single spot and with raw ratings that have a correlation of +0.986.

ChiPS rates 10 teams as being 'above-average' and rates the team in 1st (Sydney) as only a 13 point better side than the team in 6th (Geelong) on a neutral venue. (Recall that, for ChiPS, 1 Rating Point = 1 Point).

MARS rates only 9 teams as 'above-average' and, extraordinarily, now also rates all of the Top 6 teams at higher than 1,030. To get some idea of how unusual that is, note that at the same time last year it rated only the Top 3 teams that highly (Hawthorn, Sydney, and West Coast).

MoSSBODS RATINGS

MoSSBODS this week altered the Combined ranking of only six teams, this partly the result of the lower multiplier it applies in Rounds 21, 22 and 23 to differences between teams' actual and expected performances.

Those changes left Adelaide in 1st and Sydney in 2nd, and flipped GWS and Geelong into 3rd and 4th respectively. Sydney, Adelaide and GWS therefore now appear amongst the Top 4 teams for all three Rating Systems.

Looking across all 18 teams, MoSSBODS' team rankings differ from MARS' and ChiPS' by at least three places only for West Coast, which MoSSBODS ranks 7th, MARS 3rd and ChiPS 4th. There is then, as you might expect at this point in the season, broad agreement about a rough ordering of all of the teams.

MoSSBODS does, however, have a slightly larger Rating gap than ChiPS between, for example, its 1st- and 4th-ranked teams. ChiPS rates Sydney in 1st at 1,030.0 and West Coast in 4th at 1,019.6, the difference therefore being 10.4 points.

MoSSBODS rates Adelaide in 1st at +9.43 SS and Geelong in 4th at +5.48 SS, the difference therefore 3.95 SS, which equates to about 14.5 points using this year's expected conversion rate of about 53%.

Nine teams saw their MoSSBODS Offensive ranking alter this week, including Hawthorn and St Kilda sliding two places after registering only 17 and 20 Scoring Shots respectively, and Collingwood rising two places after registering 38 Scoring Shots.

On Defence, only eight teams moved, Hawthorn also sliding two places on this dimension and Collingwood also rising by two.

That left the 18 current teams arrayed as shown below, Adelaide still tip-toeing near all-time highest territory and Sydney now the only other team with a rating in the top 50% of previous Grand Finalists at this point in the home-and-away season. 

(Bear in mind that a lot of teams from earlier seasons will not appear on this chart because there was no Round 22 in their home-and-away season).

The teams' pathway to their current ratings is shown in animated form in the chart below.

Lastly, looking at a chart of the rating movements in this last week alone, the most striking feature is the small magnitude of each team's adjustment.

(Note that this week, the Lions return to this chart having been inadvertently omitted last week because I neglected to adjust the lower bound of the x-axis to cater for their lowly Defensive Rating.)

Amongst the movements, small though they are, four teams saw both their Offensive and Defensive Ratings increase:

  • GWS
  • West Coast
  • Collingwood
  • Essendon

Their opponents saw both Ratings decrease:

  • Fremantle
  • Hawthorn
  • Gold Coast
  • Western Bulldogs