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2015 - Team Ratings After Round 2

Many teams' latent abilities and inabilities were revealed this past weekend, reflected by the changes in their ChiPS and MARS Ratings and Rankings.

On ChiPS, every team's Ranking changed by at least one place, while on MARS only three teams still occupy the Ranking they held at the start of the round.

ChiPS Ratings and Rankings

The Eagles climbed highest on ChiPS, rising four places into 4th having dropped to 8th at the end of Round 1. Their ChiPS Rating of 1,015.2 is the highest it's been under the current ChiPS System since Round 10 of 2013. Other teams to climb multiple rungs were St Kilda, up three places, and Fremantle, the Kangaroos and GWS, all up two places.

Richmond fell furthest, dropping four places back to 7th, while Port Adelaide and Gold Coast fell three spots each, and Geelong fell two. Geelong's big loss to Fremantle saw them end the round with a ChiPS Rating of just 996, the first time their Rating has dropped below 1,000 under the new ChiPS System since Round 6 of 2007.

At the top of the ChiPS ladder, Sydney has now assumed 1st position, snatching it from Hawthorn on the strength of the Swans' comfortable victory over Port Adelaide, assisted a little by the Hawks' narrow, upset loss to the Dons. Both the Swans and the Hawks are now Rated by ChiPS as about 10 points or more better than any other team in the competition. The Lions, having started the season in 16th place, now find themselves Ranked last after two larger-than-expected losses.

MARS RATINGS AND RANKINGS

The Eagles were also one of the big climbers on MARS Ratings this week. They and the Kangaroos rose three places, lifting the Eagles into 5th and the Kangaroos into 7th, these MARS Rankings both one place higher than the equivalent ChiPS Rankings.

Other teams climbing multiple places on MARS were the Dogs and the Saints, who each climbed two places.

Just three teams fell multiple places over the weekend, the Tigers and the Lions falling two spots, and the Cats falling four. On MARS, the Cats retain a Rating narrowly above the "average team" 1,000, but their Rating of 1,001.1 is nonetheless the lowest it's been since Round 2 of 2007. No matter how you look at it, it seems, the Cats are at their weakest in about 8 years.

Hawthorn retains 1st position on MARS Ratings, but the gap to the Swans is now just over 4 Rating Points (RPs). Fremantle lies in 3rd about another 7 RPs further back. The Dees, after climbing off the bottom of the Rankings for a week have now retaken last place, about 3.5 RPs below the Lions.

COMPARISONS OF CHIPS AND MARS

MARS, after Round 2, Rated 10 teams above 1,000 and only eight below that mark. ChiPS, similarly, Rated nine teams above and nine below 1,000. ChiPS and MARS are similar too in that they Rate just two teams above 1,025, but where MARS has only one team Rated around 975 or below, ChiPS has four. On that basis alone, MARS seems to Rate the set of 18 teams as being more equal in abilities this year than does ChiPS. 

Recall, however, that MARS RPs are not entirely equivalent to ChiPS RPs. Using ChiPS, our best estimate of the difference in point-scoring abilities of two teams is simply the difference between their Ratings. That's how ChiPS Ratings are defined. Using MARS, however, our best estimate is 74% of the difference in the two team's Ratings. So, for example, at the moment, ChiPS Rates the Swans as about a 58 point better team than the Lions (ie 1,031.3 - 972.6), while MARS assesses the difference as being only about 35 points (ie 74% x (1,024.8 - 977.8)). Seen through this lens, MARS Ratings suggest that the differences in abilities across the teams are even smaller.

Differences in Ratings and their implications aside, ChiPS and MARS remain broadly in agreement about the Ranking of the various teams, differing in their assessments by two places or more for only five teams:

  • Essendon, Ranked 6th by ChiPS and 8th by MARS
  • Richmond, Ranked 7th by ChiPS and 9th by MARS
  • Port Adelaide, Ranked 9th by ChiPS and 6th by MARS
  • Melbourne, Ranked 16th by ChiPS and 18th by MARS
  • Gold Coast, Ranked 17th by ChiPS and 14th by MARS