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2013 : Round 1B - Wagers & Tips (Who Knows?)

Today I found myself, if only briefly, feeling something approximating sympathy for bookmakers the world over as they fielded markets on the remaining games in the 1st round of the AFL, based, surely, on nothing more than pre-season form, rumour, perhaps a little insider-knowledge, and Ablett-only-knows what else.

In any negotiation you want to encourage your adversary to bid first and reveal how he or she values the deal, and the benefits of such a strategy are only exacerbated when the information about whatever it is you're negotiating over is scarce and of indeterminate quality. So, when the TAB Bookmaker shot first - as he always must and does - posted his remaining Line markets and made a few adjustments to his existing Head-to-Head markets around noon today, it was hard not to feel sorry for him as he frantically adjusted them soon after, presumably as a slew of perhaps better-informed punters swept in and vacuumed up what they perceived to be "value".

I'd like to claim that we were amongst the cleaners, but in most cases the relevant markets either moved in a direction opposite to that which would suggest we were aligned, or didn't move at all. Perhaps we were suckers of a different kind.

In any case, here are our wagers for the remainder of the round:

(Please note that, at the time of writing, the Super Margin market for most games, including the Hawks v Cats game, which is the only one we care about, had not been posted. For now, I've shown our putative Super Margin wager on the Hawks by 10-19 points as being priced at $7.50. I'll post an update once I've secured an actual price. Note also that the Ready Reckoner that follows also assumes that this wager has been made at $7.50.

UPDATE 1pm Thursday: The market is now available and the Hawks Super Margin wager has been made at $7.50.)

In total then, five Head-to-Head wagers for a little over 6% of that Fund, four Line bets for exactly 6% of that Fund, and two Super Margin wagers for a combined 2.5% of that Fund. Combined, these 11 bets leave Investors unwagered in only the Dogs v Lions game and leave about 5% of the Recommended Portfolio hanging in the breeze.

The risks and rewards of this bravery look like this:

A highly-unexpected Giants victory represents the part-round's best-possible outcome for Investors and would add over 3c to the Recommended Portfolio, while a Dees loss would be the worst-possible outcome, shaving a bit over 1c off Investors' MAFL wealth.

Next, to tips and predictions.

This week, let's take a game-by-game approach to this information.

Thursday: Carlton v Richmond

It's hard to call this game as other than a Carlton win, as the Head-to-Head Tipsters have it as a lock for the Blues; the Probability Predictors assess it, on average, as being 65% likely that the Blues will win; and, amongst the Margin Predictors, only the arch-contrarian Combo_NN2 has been able to find a win for the Tigers. Even then, it's predicting only a very small victory margin for the Tigers. Across all the Margin Predictors, the average predicted margin of victory for the Blues is just over 10 points. 

The Line Fund algorithm, seeing a 6.5 point start for the Tigers, rates the Blues' chances of overcoming this handicap at about 58%.

Saturday: Western Bulldogs v Brisbane Lions

This is another game where opinion is broadly unanimous. Amongst the Head-to-Head Predictors, only Home Sweet Home predicts a Dogs victory. The Margin Predictors are siding with the away team by margins in a narrow range spanning just 15 points from 7 to 22, while the Probability Predictors are also startlingly aligned in rating the Dogs as underdogs, assessing their chances of springing the upset as ranging between just 29% and 35%.

According to the Line Fund algorithm even a 17.5 points start for the Dogs isn't enough and makes them just 43% prospects on line betting.

Saturday: GWS v Sydney

In yet another game where opinion is solidly behind the away team, only Home Sweet Home amongst the Head-to-Head Predictors is predicting a home team win. Here, the Margin Predictors' range of away team victory margins is far broader and spans 15 to 61 points with an average of just over 32 points, while the Probability Predictors rate GWS as between 6% and 26% chances.

The Line Fund algorithm assesses the Giants' 48.5 points start as being overly generous and, accordingly, attaches a 63% probability to their protecting this handicap and triumphing on line betting.

Saturday: Gold Coast v St Kilda

Once more, in this game opinion is solidly behind the away team and only Home Sweet Home amongst the Head-to-Head Predictors naively predicts a home team win. The Margin Predictors are prophesying victory margins of between 7 to 28 points with an average of just over 17 points, while the Probability Predictors rate the Suns as between 15% and 30% chances.

The Gold Coast's 24.5 point start just isn't quite enough to persuade the Line Fund algorithm to select the them as line betting victors. It has them as just 48% chances.

Sunday: Melbourne v Port Adelaide

In this game there's some support for the home team, and it's from relatively well-credentialled Tipsters and Predictors, amongst them BKB himself. The Head-to-Head Predictors are split 9-4 in favour of Port, while the Margin Predictors are all but unanimous in predicting a home team victory; here it's only Combo_NN2 dissenting. The Probability Predictors all foresee a Dees win but rate their chances as lying in a broad range between 52% and 81%.

With Melbourne giving only 2.5 points start on line betting, the Line Fund algorithm is resolutely behind the Dees, rating them 59% chances of winning on line betting.

Sunday: Kangaroos v Collingwood

It's the away team that, again, enjoys majority support in this clash, with only Home Sweet Home amongst the Head-to-Head Predictors predicting a home team upset. That said, the Margin Predictors aren't foreseeing a runaway victory for the Pies, with predicted margins ranging only from 5 to 19 points, though the Probability Predictors assess the Roos' chances as lying in a fairly narrow range between 28% and 35%.

A start of 14.5 points has been enough though to install the Roos as 57% favourites on line betting with the Line Fund algorithm.

Monday: Hawthorn v Geelong

Perhaps a bit surprisingly, the Hawks are unanimous favourites amongst the Head-to-Head Predictors, predicted to win by between 2 and 18 points according to the Margin Predictors, and rated 53% to 72% chances by the collected Probability Predictors. Even the Line Fund algorithm narrowly fancies the Hawks' chances on line betting giving the Cats 9.5 points start: it assesses them as 51% chances to cover that spread. 

Conformity and Individualism

To finish, I'd note that, amongst the Margin Predictors, it's ProPred_7 that's wound up being the Round's most average Predictor, with a mean absolute difference from the all-Predictor average margin of just 2.7 points per game. In contrast, WinPred_9 has been the most consistently individualistic Margin Predictor, recording a mean absolute difference of 9.9 points per game.

Amongst the Probability Predictors it's also a ProPred that's also the most average. The mean absolute percentage point difference in its probability predictions for the round relative to the all-Predictor average was just 3.4% points per game. WinPred recorded the largest difference at a little over 10% points per game.