2017 - Round 27 (Grand Final Week) : It's Adelaide's! (Probably)

This week, our lone contrarian forecaster is MoSSBODS who's narrowly come down in favour of the Tigers. All the other Head-to-Head Tipsters have gone with the Crows.

MoSSBODS' "courageous" tip means that it will finish the season leading by either three tips or one, and the unanimity amongst the rest of the Tipsters means that they will all finish in the spots they now occupy. 

Amongst the Margin Predictors, C_Marg is the most optimistic about the Crows' chances, it forecasting a 28-point victory for the favourites. Least optimistic amongst the Predictors still opting for a Crows win is ENS_Linear, who has the Crows winning by just 2 points.

From the perspective of the Margin Predictor Leaderboard however, the key issue is the difference between MoSHBODS_Marg and the two RSMP Predictors. At just 6 points, MoSHBODS_Marg is now guaranteed to finish in top spot by at least 10 points.

That's an astonishingly close margin when you consider that the aggregate absolute error for MoSHBODS_Marg across the 206 games so far this season is just under 6,000 points. Against that metric, the gap between MoSHBODS_Marg and RSMP_Simple is a mere 0.027%.

Across the Head-to-Head Probability Predictors, the low estimate for Adelaide's chances is MoSSBODS_Prob's 49%, and the high estimate C_Prob's 78%. MoSHBODS_Prob's estimate is virtually identical to the three Bookie-based Predictors, which means that it will finish the season atop that Leaderboard.

So, we'll finish 2017 with a MoS forecaster beating out the bookmakers and heading all three Leaderboards - with a MoSSBODS variant heading the Head-to-Head Tipsters, and two MoSHBODS variants heading the Margin Predictors and Head-to-Head Probability Predictors.

I'd most certainly have settled for that back in March.


Nothing but crickets on the wagering front this week, with MoSHBODS wanting at least $2.40 to take a punt on the Tigers, and MoSSBODS, for a line bet, wanting the Crows to get at least 9.5 points start or the Tigers to get at least 7.5 points start. We were very close with Centrebet's 6.5 points start.

As well, for an over/under bet, MoSSBODS was looking for a Total of 167.5 or less, or of 180.5 or more. Centrebet was again closest, but 3 points too high.

So, wagering for the year is now complete and, thanks to the combined abilities of the MoS twins, quite a successful year's wagering it's been.

Almost certainly, I'll be back next year using these same algorithms. At this stage the only analysis I'd like to perform with a view to some sort of tweaking would be to review MoSSBODS' versus MoSHBODS' over/under performances.

We'll do more of a wrap on the season's wagering in blogs next week.

All four forecasters foresee a relatively low-scoring Grand Final, with Totals ranging from 170.5 to 174 points.

Adelaide are forecast to score between 86 and 90 points, and Richmond between 82 and 88 points.

The overlays against both bookmakers are quite small.

Last week, MoSSBODS and MoSHBODS finished on the right side of the two bookmakers' Totals in one of the two games. As a result, MoSHBODS' season-long record against both the TAB and Centrebet now stand at 105 from 206 (or 51%), and MoSSBODS' at 104 from 206 (or 50.5%). (Note that these numbers and the table below, include a correction to the Round 4 results for both MoSSBODS and MoSHBODS.)

In terms of mean absolute errors (MAEs), last week (and for the second week running), MoSSBODS outperformed on every metric except Totals, with an MAE on game Margins of 27.2 points per game, on Home team scores of 25.6 points, and on Away team scores of 4.9 points. MoSHBODS did best on Totals with an MAE of 22.1 points per game.

That left MoSHBODS with the best season-long performance on game Margins (29.0), Centrebet with the best MAE for Home team scores (18.0), and the TAB with the best MAE on Away team scores (17.2) and on Totals (20.7).