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2014 - Round 21 : Happy With The Draw

If you're not a fan of SuperMargin wagers - and, let's be honest, who is? - this weekend might be one where you're better off doing something other than tracking the fate of MoS wagering.

All up, Investors have 14 SuperMargin wagers including one on a draw in the Fremantle v Hawthorn game priced at $41. Landing a wager on a draw is something still on the MoS bucket list. Two pairs of the seven we have form Chasms of Despair. The good news is that with the 1% cap on SuperMargin wagers and the 20% weighting of the Margin Fund in the Recommended Portfolio, those 14 bets represent less than 3% if the total original Portfolio.

About the same proportion has been put at risk by the Head-to-Head Fund, but in its case via a single wager of about 9% of the Fund on Freo at $1.70. The Fund's algorithm showcased its non-linear inscrutability this week by opting out of an additional wager on the Gold Coast, which it fancied early in the week when they were priced at $2.80 but went right off when their price drifted to $3.00. Sometimes, I guess, price can act as a signaller of quality.

Meantime the Line Fund, apparently unchastened by its 3 and 8 performance over the past two weeks, rates the chances of five home teams sufficiently highly to risk about the same proportion of the Portfolio on them as has been risked by the Head-to-Head and Margin Funds combined.Three of the teams wagered on by the Line Fund are giving start - Freo amongst them, if only barely - while two are receiving it.

With Freo carrying bets of all three types - Head-to-Head, Line and SuperMargin - on its recently rickety back, a large proportion of the round's upside and downside vests with them. In fact, they mitigate 37% of the total upside and 14% of the total downside.

That game aside, no other contest is associated with more than about a 1 to 1.5% upside or downside except the Crows v Tigers game where a 16 to 19 point win by the home team would lift the Recommended Portfolio by 3.5c.

Total upside for the week is slightly less than 17c and total downside slightly less than 12c. 

TIPS AND PREDICTIONS

In only three games this week do fewer than three Head-to-Head Tipsters disagree with the consensus. None disagree that the Roos will beat the Dogs, or that the Swans will beat the Saints, and only Easily Impressed I and Home Sweet Home reckon that the Blues will upset the Cats.

In contests at the other end of the disagreement scale the Tipsters are split 15-13 in favour of the Dees over the Suns, and are split 16-12 in favour of the Dockers over the Hawks.

So high and, to some extent, so concentrated are the levels of disagreement this week that eight of the Tipsters have Disagreement Indexes of above 30%. Four have Indexes of 50% meaning that a randomly chosen Tipster in a randomly chosen game would be just as likely to agree with, for example, Shadow, as to disagree with them.

In contrast, in only three games is there any disagreement at all amongst the Margin Predictors and in one of those games the disagreement stems from a single Predictor, Combo_NN_1, predicting an upset Eagles win over the Dons. The Dees v Suns game sees six Predictors tipping a narrow win for the away team, and the Dockers v Hawks game sees five different Predictors doing the same thing.

Win_3, Win_7, Combo_NN_1 and Combo_NN_2 have the round's highest Mean Absolute Deviation (MAD) from the all-Predictor average this week, while Combo_7, Bookie_9, ProPred_3 and ProPred_7 have the lowest. It's interesting to note that two of the Predictors from that first list and two from the second are in the current Top 5 Predictors by MAPE on the MoS Leaderboard.

More similar to the Margin Predictors than the Head-to-Head Tipsters are the Head-to-Head Probability Predictors this week, with disagreement amongst them arising only in the final two games of the round. In the Melbourne v GWS game they're split 5-3 in favour of the Dees, and in the Fremantle v Hawthorn game C_Prob alone has sided with the Hawks. These two games, plus the Dons v Eagles game, are the only ones where the range of probability assessments spans more than 30% points.

WinPred and C_Prob have the round's highest MADs by some distance, while ProPred have comfortably the round's lowest.

Finally, to ChiPS, which this week makes one of its largest margin predictions in tipping the Swans to defeat the Saints by 77 points on Saturday. It's returned this week to the policy of tipping the team with the higher Rating as the more likely winner and with basing the likely margin of that victory most heavily on the difference in those Ratings.

At current TAB prices, only the Suns and the Dees are deemed by ChiPS as being worthy of a wager, and in both cases only small ones.