Matter of Stats

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2018 - Team Ratings After Round 7

I've been hearing a lot of references recently - especially from US pundits - about people "not wanting to get over their skis" and, in that spirit, I'm cautious about overstating the Tigers' dominance at this point in the season. MoSSBODS and MoSHBODS, however, seem to be deeply dispassionately enamoured with them at the moment.

MoSSBODS has Richmond as about 5.5 scoring shots better than any other team in the competition, which translates to about a 20 point premium; MoSHBODS has the gap at about 21 points.

They disagree about which team lies in second place though, MoSSBODS opting for GWS while MoSHBODS prefers West Coast, and they also disagree about which team lies in every other position down to 11th. Once you get past Richmond, however, it is something of a log-jam of ratings down to 11th. For MoSSBODS the ratings gap from 2nd to 11th is just 3.3 scoring shots (or about 12 points) and for MoSHBODS it's just under 11 points.

Adelaide remains the team most difficult to rank, with MoSSBODS placing them no higher than 8th and MoSHBODS placing them 3rd. No other team is ranked more than two places differently by the two Systems.

Richmond's ratings dominance comes not from either their offensive or defensive abilities, but from both. MoSSBODS has them as over 3 scoring shots superior to Adelaide offensively and as over 2 scoring shots superior to GWS defensively. MoSHBODS has the same teams second on both dimensions and has Richmond with just over a 7 point lead defensively and offensively.

Looking across all 18 teams we find that:

  • GWS is ranked 4th by MoSSBODS on Offence and 8th by MoSHBODS
  • Geelong is ranked 8th by MoSSBODS on Defence and 5th by MoSHBODS

No other team is ranked more than two places differently by the two Systems on either rating component. It's reassuring to be seeing greater levels of agreement emerging now after each week's results.

Just how quickly Richmond have put a gap between themselves and the rest of the pack can be seen in the animated GIF below, which tracks each team's ratings at the end of all seven rounds. 

We can put Richmond's dominance into an historical context by looking at how its and the other 2018 teams' MoSSBODS Ratings compare with those of previous Grand Finalists and other teams at the same point in the season (ie after Round 7). 

Richmond is clearly breathing in some rarefied air at the moment, but I am mindful of the similar situations in which the Crows have found themselves in recent seasons, so I'm not at all ready to make brave pronouncements just yet. Still, you'd prefer to be a Richmond supporter right about now than a supporter of any other team.

The Tigers aside, we can still see the rating effects of generally low-scoring games. It remains the case that only the top 8 teams have positive ratings on offence while on defence the top 12 do.

Lastly, let's take a look at ChiPS and MARS, where we see Richmond's dominance reflected in ChiPS ratings but far less so in MARS ratings where the Crows continue to enjoy a well-above average rating.

ChiPS has an unchanged top 3 of Richmond, GWS and then Sydney, while MARS has it as Richmond, Adelaide and then Geelong.

Despite the differences in the teams they choose to rank 2nd and 3rd, the two Systems differ by more than two places in their rankings of only three teams:

  • GWS (ranked 2nd on ChiPS and 6th on MARS)
  • Adelaide (ranked 9th on ChiPS and 2nd on MARS)
  • Western Bulldogs (ranked 15th on ChiPS and 12th on MARS)

And, finally, broadening our comparison to look across the team rankings of all four Systems, comparing them with the current competition ladder, we find that:

  • Hawthorn's, Gold Coast's, North Melbourne's, and Sydney's ladder positions are most different from their average Rating System ranking. The first three teams on that list are higher on the ladder, and the last lower on the ladder than their ratings would lead us to expect.
  • Adelaide (2nd to 9th) is ranked seven places differently across the Rating Systems.
  • Hawthorn (5th to 10th) is ranked five places differently across the Rating Systems.
  • West Coast (2nd to 6th) is ranked four places differently across the Rating Systems.
  • Collingwood (5th to 9th) is ranked four places differently across the Rating Systems.
  • No other team is ranked more than three places differently across the Rating Systems.