Matter of Stats

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2017 - Team Ratings After Round 1

We noted last year that Adelaide, as far as the MoS Team Rating Systems were concerned, were very unlucky not to progress further in the competition. Their big win over GWS this weekend only served to reinforce that view.

Let's start by looking at the Combined (ie Offensive plus Defensive) ratings and rankings of MoSSBODS and MoSHBODS.

Both Systems rank Adelaide as the number 1 team, MoSSBODS assessing them as over 7 Scoring Shots better than an average team when playing at a neutral venue, and MoSHBODS assessing them as almost 4.5 goals better than the same such average team. 

(For details on how MoSSBODS and MoSHBODS have been built and how to interpret their ratings, follow this link).

MoSSBODS has the Bulldogs in 2nd, then Geelong, GWS and Sydney. MoSHBODS puts the Dogs at the bottom of that grouping, and ranks Geelong, GWS and Sydney in the same order above them.

This similarity of team ranking persists as we move down the list. In fact, the Western Bulldogs is the only team for which the two Systems' rankings differ by more than one spot. All this despite the fact that 16 teams changed ranking on MoSSBODS and 12 on MoSHBODS on the basis of the weekend's results.

Perhaps the only other comparison of interest is that Melbourne is rated a very slightly above-average team by MoSSBODS and a very slightly below-average team by MoSHBODS.

Turning next to the component ratings we find that Adelaide is rated as the best team offensively by both MoSSBODS and MoSHBODS, and the Western Bulldogs are rated as the best team defensively, albeit it to a lesser extent after the Dogs allowed the Pies 26 Scoring Shots on Friday night.

Looking just at the Offensive rankings we that only the Western Bulldogs are ranked significantly differently by the two Systems, MoSSBODS putting them 7th and MoSHBODS 10th.

On Defence, no team is ranked more than a single spot differently by the two Systems.

I'll admit to being a bit surprised about the very high levels of agreement between MoSSBODS and MoSHBODS at this early point in the season, but hope this can be interpreted as convergent validity rather than shared miscalibration.

Lastly for this week, let's take a look at MoS' veteran Team Rating Systems, MARS and ChiPS.

They also have the Crows in top spot, but rank West Coast a little more highly (2nd and 3rd) than do MoSSBODS and MoSHBODS (6th and 6th).

Again though, the overall picture is one of broad agreement where the only other mild divergences are Sydney's #2 ranking and Collingwood's #11 ranking by MARS.

At this point of the season it seems that one hymn book is sufficient.