2012 MARS, Colley, Massey and ODM Ratings After Round 11
This week marked a couple of firsts for the season: the first time any team enjoyed a bye, and the first time that one team has met another for the second time during this season (St Kilda and the Gold Coast).
As a consequence of the bye I'll not be reporting this week on the movement in MARS Ratings across the five most recent rounds. This feature will return in a couple of weeks when all teams will have again played the same number of games.
On the issue of the commencement of reciprocal team matchups, in seasons past I've made no adjustment to MARS, Massey or Colley Ratings to cater for this phenomenon and, for now, I've no intention of breaking with this tradition for these Ratings System.
The ODM Rating System, however, can readily be altered to cater for multiple team meetings simply by averaging the scores of all games played between any pair of teams. This week I've calculated ODM Ratings with and without this adjustment and, as I'll note later, ultimately opted to use the adjusted Ratings.
First though to MARS Ratings, where we see remarkably little movement in team Ratings due to Round 11 results.
In fact, only the top 2 teams, Hawthorn and Collingwood, traded places, and this despite the fact that both teams had victories on the weekend. Hawthorn's away win over Port was deemed by MARS more Ratings Point-worthy than was the Pies' similarly-sized win over the Dees, also away from home (at least notionally).
Hawthorn and Geelong remain barnacled to the MARS top 4, even though they lie respectively only 6th and 7th on the competition ladder. Essendon, Adelaide and, to a lesser extent, Sydney, remain absent from MARS' highest-rated teams.
Whilst MARS remained mostly unshaken in its opinions on the strength of Round 11 results, Colley saw fit to re-rank seven teams. It moved four teams by just a single spot, but also dropped Carlton and Essendon two spots each, and elevated Fremantle by the same amount. Collingwood, Adelaide and West Coast, the top 4 from the competition ladder, remain its top 3 teams.
Massey re-ranked just five teams, most dramatically dropping Collingwood by 3 spots into 8th, unimpressed, somewhat like MARS, by their 42-point win over the Dees, and elevating the Saints by 4 spots into 4th on the back of their 95-point victory over the Suns. Evidence, perhaps, that I should also be thinking about adjusting the inputs to Massey Ratings to cater for multiple team meetings, especially when they're between the minnows and the mighty.
(I should note that Colley, unlike Massey, focusses on wins and losses rather than margins of victory and so is less subject to the potentially distorting influence of repeated blowout victories between mismatched teams.)
ODM, once I adjusted the input matrix it uses to calculate team ratings by dividing the aggregate St Kilda v Gold Coast results by 2, re-ranked six teams. It swapped Fremantle and Port Adelaide in 11th and 12th, lifted Essendon from 7th to 5th and West Coast from 6th to 4th, and dropped Collingwood from 4th to 6th and Richmond from 5th to 7th. Only Colley, it seems, thought much of the Pies' win over the Dees.
Without the adjustment to the input matrix, four teams would be ranked differently by ODM: Collingwood and St Kilda would swap 6th and 8th, while Essendon and West Coast would swap 4th and 5th. Collingwood's victory might have been less than impressive this week, but I don't think it was unconvincing enough to drop them 4 spots into 8th. As well, the Saints don't deserve to grab two spots on the basis of pulverising the Suns - hence my decision to run with the ODM Ratings using the adjusted input matrix.
Comparing each Rating System's team ranking with the average ranking across all Systems we now find that:
- Colley ranks five teams at least 3 places higher or lower than the all-System average. It ranks Adelaide, Collingwood and Fremantle higher, and Hawthorn and St Kilda lower than this average.
- Massey ranks just three teams at least 3 places higher or lower than the all-System average, rating Richmond and St Kilda higher, and Collingwood lower.
- ODM ranks no teams at all 3 places higher or lower than the all-System average.
- MARS, like Colley, ranks five teams at least 3 places higher or lower than the all-System average. It ranks Carlton and Geelong higher, and Adelaide, Port Adelaide and Sydney lower. It's interesting to note that MARS' elevated opinion of the Saints is now being enthusiastically supported by Massey, remains laughable to Colley, yet still seems mildly aberrant to ODM.