Matter of Stats

View Original

AFLW 2022 Spring Edition - Round 13 - Results

Very close to a perfect round from WoSHBODS this week as it tipped both winners and finished with a 2.5 points per game Mean Absolute Error for the Game Margins, and an 11.3 points per game Mean Absolute Error for the Game Totals.

That left it with the all-season results below.

We can break down that overall Margin MAE of 18.9 points per game into team-by-team contributions, which we do in the table at right and which shows that WoSHBODS has been particularly precise in game margins for matches involving the Dees, Dogs, Blues, Pies, and Hawks, and particularly imprecise in game margins for matches involving the Giants, Swans, and Saints.

Looking solely at the four expansion teams - none of which made finals - we have Hawthorn and Essendon still well under the all-team average, Port Adelaide at just over the average, and Sydney much higher than the average.

Altogether, nine teams have MAEs below the all-team average, and nine have MAEs above the all-team average.

We can also break down the overall Margin MAE based on the size of the eventual victory, which we do in the table at left and which shows that, still, it has been the larger victories where the forecasts have been least accurate, and the narrower victories where they have been most accurate, although games won by between 12 and 17 points have still seen somewhat lower-than-expected accuracy.

WoSHBODS has tended to be more precise in its margin forecasts in games that were won by relatively large margins. It is 31.5 from 49 (64%) in games won by under 3 goals, and 42.5 from 49 (87%) in games won by 3 goals or more.

The Log Probability Scores can also be analysed by team, and the results of doing this are shown in the table at right where we assign one half of the LPS for a game to each of the two teams.

Here we see that WoSHBODS’ probability estimates have resulted in strong LPS returns from the Dees, Dogs, Swans, Crows, Pies, Dockers, and Roos, and weak and negative returns from the Eagles, Tigers, and Blues.

Overall, there have been positive LPS contributions from 15 teams, and negative contributions from only three.