2019 - Team Ratings After Round 9
/Just how much effect a serious blowout victory should have on a team’s rating is an interesting thing to ponder, but my historical optimisation efforts - at least for MoSSBODS and MoSHBODS - suggest that putting a cap on the size of the adjustment is suboptimal.
So it is that GWS, on the back of a 93-point and 28-scoring shot victory over Carlton, added 1.9 Scoring Shots to their MoSSBODS Rating and 6 points to their MoSHBODS Rating, which lifted them two places on both Systems and into top spot.
Below them on both Systems - though only barely in the case of MoSSBODS - is Collingwood who are then followed by, in order, Geelong and Richmond.
On MoSSBODS and MoSHBODS, six teams stayed in the same place this week while the rest moved by no more than two places, which makes this probably the quietest week for ranking changes so far this season.
Those moves have left the Systems now differing in their rankings of all but the Dees, Eagles and Dockers by no more than two places. The Dees are 9th on MoSSBODS and 13th on MoSHBODS, the Eagles still 12th on MoSSBODS and 9th on MoSHBODS, while the Dockers are 15th on MoSSBODS and 11th on MoSHBODS.
Seven teams - MoSSBODS Top 6 plus the 8th-placed Crows - now have a positive Combined Rating on both Systems, while the Dogs have a positive MoSSBODS but a negative MoSHBODS Combined Rating. The gap between 1st and 8th on MoSSBODS now stands at 4.7 Scoring Shots (down 0.7), and between 1st and 8th on MoSHBODS at 20.4 points (up 1.3).
On the component ratings, GWS has now moved into 1st on offence on both Systems, while Collingwood has held on to 1st on defence on both Systems. GWS is 2nd on defence, and Collingwood 2nd on offence under both Systems.
On MoSSBODS, 8 teams are now rated positively on offence and defence (no change), 4 are rated negatively on both (no change), 1 is rated positively on offence but negatively on defence (down 1), and 5 are rated negatively on offence but positively on defence (up 1).
Three teams are now in different quadrants under the two Systems:
Port Adelaide (positive offence and defence on MoSSBODS, negative offence but positive defence on MoSHBODS)
Western Bulldogs (positive offence and defence on MoSSBODS, positive offence but negative defence on MoSHBODS)
Melbourne (negative offence but positive defence on MoSSBODS, negative offence and defence on MoSHBODS)
Looking across all 18 teams we find that:
on offence, only two teams are ranked more than 2 spots differently by the two Systems (Port Adelaide and Essendon)
on defence, only two teams are ranked more than 2 spots differently by the two Systems (Melbourne and West Coast), though the differences in rankings for those two teams are quite large
Next, let’s compare each team’s current ratings with those of teams from the past at the same point in their respective seasons (ie after eight rounds of the home-and-away season).
Teams shown as red points are teams that eventually finished premiers, and those shown in orange finished as runners up.
Collingwood and GWS are now the only teams with a Combined Rating at or above the median for all previous Grand Finalists at this point in the season, and Richmond, Geelong, Port Adelaide and Essendon (barely) the only other teams with Combined Ratings above the lowest decile for all previous Grand Finalists.
If we focus purely on those seasons from 2000 on, we obtain a similar picture.
The following animation shows the path that each team has followed, at the end of each round, to get to its current rating, and highlights, in particular, the leap that GWS enjoyed this week (and the slide that Carlton suffered).
(It’s also interesting to note the rlatively rare position that Brisbane Lions find themselves in now, with quite a high offensive but low defensive rating.)
ChiPS and MARS, once again, left Geelong and Collingwood in 1st and 2nd spots this week. MARS left GWS in 3rd, and ChiPS did likewise with Richmond.
No team moved by more than two places under either System, and 13 moved not at all on ChiPS, and 12 not at all on MARS, mirroring the stability we saw from the MoS twins above.
That’s left the two of them disagreeing about the ranking of only the Western Bulldogs and Melbourne by more than two places. Both still have the same nine teams as better-than-average teams (ie rated over 1,000) and the same nine teams as worse-than-average teams.
Looking across the rankings of all four Systems and ordering the teams based on the current competition ladder, we find that:
Western Bulldogs now has the widest range of rankings (7th on MoSSBODS and 15 on MARS)
Sydney and West Coast have the next-widest range of rankings (Sydney is 10th on ChiPS and 16th on MoSSBODS and MoSHBODS; West Coast is 6th on MARS and 12th on MoSSBODS)
No other team is ranked more than four places differently across the four Systems.
Collingwood, Gold Coast and Carlton are now the only teams ranked identically by all four Systems, but six other teams’ rankings cover only two or three values.
We now see fairly large positive differences between ladder position and Rating System rankings (ie red dots, where Rating System ranking is much lower than ladder position) for only the Lions and Dockers, and large negative differences (ie green dots) for, still, only the Dons.
