2011 Round 8: The Forward Estimates Show a Surplus in 2011

For the first time since Round 5, both the Head-to-Head and the Line Fund have failed to find value in a contest. It's the Brisbane v Essendon clash on Saturday that's bereft of financial interest, and represents the first time this season that Investors have not had a wager in a contest involving the Lions. (It's the third time, however, that a Dons clash has gone unwagered upon.)

What Investors do have are 3 head-to-head wagers, the largest an uncomfortable 10.7% on the Swans at $1.12 facing Port Adelaide at the SCG, and the two others far more modestly sized wagers on Geelong (2.5% at $2.80) and West Coast (1.8% at $2.00) in the first and last games of the round.

They also own 6 line bets, the first three on away teams in the form of the Pies, Dees and Suns for amounts ranging from 0.9% (on the Dees) to 3.5% (on the Pies), and the last three on home teams in the form of the Hawks, Dogs and Eagles and all for large stakes. Largest amongst this trio is a 6.7% bet on the Hawks giving 20.5 points start to the Saints and playing at the G.

Here's all that in the by now familiar format:

A spread-covering win by the Hawks or an Eagles victory by any margin provide the Round's greatest upside for Investors at around 3%, while any of a Swans loss, a Hawks loss, an Eagles loss of any magnitude greater than a couple of points, or an insufficiently decisive Pies victory all carry downside of a similar or larger size.

This week, a more visual way of presenting the Ready Reckoner (which can be viewed in a larger format if you click on it):

It's interesting to see that only an apparently narrow range of scores in the Cats v Pies game - a draw or a Pies win by fewer than 17 points - will lead to a punting loss. Of course as far as the TAB Sportsbet bookmaker is concerned, these scores are among the most likely final results, but there is some visual comfort, albeit illusory, in the boundless strips of green flanking that molten pit of despair. In every other contest - as it has been for most contests so far this season - it's the pit that's boundless in one direction.

So, what do the Head-to-Head tipsters think about the round?

In only two games is there anything more than token controversy across the head-to-head tipsters. In the Eagles v Freo clash, where Freo's the $1.75 favourite, majority support is with the Dockers but only by 8 votes to 5. The Adelaide v Gold Coast game is the other game with the same aggregate tipping result; surprisingly the 8 votes are for the $5.50 Suns and the 5 votes are for the $1.13 Crows.

Elsewhere, the underdog Cats and Tigers, and the narrowly-favourited Dees enjoy 10-3 support, Essendon enjoy all-but unanimous support with Home Sweet Home the only holdout, and Sydney and Hawthorn all enjoy the full confidence of the House.

The Margin Predictors see many of the clashes quite differently:

As a group, they're siding with the favourites in every game but the last, which means they differ from the head-to-head tipsters in half the matches, predicting victories for the Pies, the Crows, the Dogs and Freo, when the head-to-head tipsters predict the opposite outcomes.

Their average predicted victory margins are narrowest for the West Coast v Fremantle game (where the average is for a wafer-thin Eagles victory), the Roos v Melbourne game (where the average is for about a 1 point Melbourne victory), and the Geelong v Collingwood game (where the average result is a victory for the Pies by just over 4 points).

Blowouts are possibilities as far as the Margin Predictors are concerned in the Adelaide v Gold Coast and Sydney v Port Adelaide games.

Here are the week's manhattan distances for each pair of Margin Predictors:

The distances most relevant to the MAPE leaderboard are those involving Bookie_3, Bookie_9, Combo_7 and Combo_NN_2, which currently fill positions 1st through 4th. Combo_NN_2's predictions are relatively distant from the three other Predictors this week, within manhattan distances ranging from about 50 to 90 points. Indeed, these predictions are, compared to each of the three other Predictors, more distant than they were in Round 7, though that didn't work out so well for Combo_NN_2 in that instance. 

Finally, to the Probability Predictors, where the week's major disagreement is ProPred's rating of the Cats as 65% chances while its co-prognosticators rate them as only 33%-44% chances. Less dramatic differences are in evidence for the Roos v Melbourne game where ProPred and WinPred rate the Roos as 55% chances, while the Bookie and H2H rate them as 47% chances.

In the Dogs v Tigers game, WinPred is the outlier in rating Richmond as 53% favourites, and in the Eagles v Freo game ProPred, WinPred and H2H all disagree with the Bookie, who has the Eagles as only 47% chances, and rate them as between 54% and 59% chances.