Inferring Finals Chances From MARS Team Ratings

If the Dogs make this year's Grand Final they'll also make history as the lowest MARS Rated team after 5 rounds to do so in the modern era. Their Rating of 993.6 is 5 Rating Points (RPs) lower than the losing Grand Finalists of 2000, Melbourne, whose Rating after Round 5 in that year was 998.6.

Making the Prelim Finals, while certainly less remarkable, would still count as something of an historic achievement since only four teams have progressed that far into the Finals in the past 15 seasons after having had lower MARS Ratings after Round 5:

  • Geelong in 2004, whose Rating was 987.3 (and record was 1-4)
  • The Kangaroos in 2007, whose Rating was 990.5 (and record was 2-3 having been 0-3 earlier)
  • West Coast in 2011, whose Rating was 986.0 (and record was 2-2 with a bye and losses in their two previous games)
  • Adelaide in 2012, whose Rating was 992.9 (and record was 4-1, the 4 wins including 2 against the Suns and the Giants, and the single loss a 56-point defeat by the Hawks. Adelaide also started the season with a low Rating of around 987.)

That Adelaide 2012 team is perhaps the most similar to the Dogs of 2015, since the Dogs also started the season with a fairly low Rating (986) and currently have a 4-1 record.

Moving from the specific and the extreme to the general and the average, a look at the past 15 seasons' Finalists reveals that the average Elimination Finalist has been Rated about 1,004 after Round 5, the average Semi- and Preliminary Finalist has been Rated about 1,008, and the average Grand Finalist has been Rated about 1,021.

Another way to look at the data that makes it more directly applicable to the current season is to summarise how teams with specific Ratings at the end of Round 5 in a season have ultimately fared in terms of Finals appearances.

Here you can see, for example, that 92% of teams whose Rating was below 990 at the end of Round 5 subsequently missed the Finals. In 2015, such a group would include GWS, so they too will need to make some sort of history if they are to stay in the Top 8 for the remainder of the season.

This table might loosely be interpreted as suggesting the following demarcation of teams:

  • Grand Final aspirants: Sydney, Fremantle and Hawthorn
  • Semi- and Prelim Final aspirants: Port Adelaide, West Coast, Adelaide and Collingwood
  • Potential other Finalists : Geelong, Essendon, Richmond and the Kangaroos, with the Western Bulldogs also having some chance

There's nothing especially startling about those suggestions, I'd submit, but it's interesting that even at this relatively early stage of the season MARS Ratings are beginning to provide hints about who might proceed into September.