2016 Round 16 : Overs/Unders Update

The Overs/Unders Fund has gone all Goldilocks on more than half of the weekend's TAB Totals, declaring them "just right" and thus unsuitable for any investment. 

To torture that fairy tale analogy for just a moment longer, of the remaining four contests, three have elicited the response "this Total is too high!" and the other "this Total is too low!". So, four bets it is (and there will be no porridge for anyone ...)

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Those four fresh wagers, when added to the four head-to-head and four line bets, put just under 9% of the original Overall Portfolio at risk, the most that's been wagered in a single round since the last time the Funds had the 9-game smorgasbord.

MoSSBODS COMPARISON TO THE TAB

I have some news on the apparent bias of MoSSBODS in estimating Totals. I believe I have found the source and the fix, but analysed and confirmed it too late to apply to this week's estimates. Later this week or over the weekend I'll be writing a short piece explaining what I've found and what I'll be doing from Round 17 onwards.

In the meantime though, we're stuck with the traditional MoSSBODS approach, which this week sees it predicting lower scores for 14 of the 18 teams when compared with the TAB's implicit forecasts.

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That story's fairly familiar by now. What's slightly less expected, however, is the magnitude of MoSSBODS' differences of opinion with the TAB in terms of game margins this week. In six of the games, MoSSBODS differs, in absolute terms, by more than 2 goals and, for two of those games (Port Adelaide v Hawthorn, and Gold Coast v Brisbane Lions), that difference is large enough to see MoSSBODS' forecasts on the opposite side of zero to the TAB's. 

On a team-by-team basis, MoSSBODS differs most of all in its forecast for the Swans' score, which it pegs at 57 points to the TAB's 79, and for the Dees, who MoSSBODS expects to score 73 and the TAB 95.

MoSSBODS' and the TAB's opinions about which games are most likely to be the lowest- and highest-scoring are more in accord, however, with both reckoning the Cats v Swans, and Dees v Dockers games are likely to be less troubling for the scorers, and that the Suns/Lions game will be a 50-points a quarter "we don't need no stinkin' defence" scorefest.

Lastly, an update on the relative performance of MoSSBODS (as it now functions) and the TAB so far this season:

• Home Team Scores:
  MoSSBODS - MAE 20.4 / Mean Error +8
  TAB - MAE 18.2 / Mean Error +3
   
• Away Team Scores:
  MoSSBODS - MAE 19.4 / Mean Error +1
  TAB - MAE 19.9 / Mean Error -5
   
• Aggregate Scores:
  MoSSBODS - MAE 27.2 / Mean Error +9
  TAB - MAE 24.9 / Mean Error -2
   
• Game Margin:
  MoSSBODS - MAE 29.2 / Mean Error +7
  TAB - MAE 28.8 / Mean Error +8

As always, errors are calculated as Actual - Predicted.