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2015 - Round 27 : Hawks, But Not By Much

It's a source of continuing frustration to me that determining "Home Ground" status remains problematic from time-to-time, especially during the Finals. Resolving this for season 2016 is very high up on my to-do list.

This week the issue arises because, officially, Hawthorn are the home team for the Grand Final - based on the fact, as I now understand, that they were the winners of the 1st Preliminary Final - despite having finished below the Eagles at the end of the home-and-away season. For the purposes of modelling I've ignored the AFL's designation and treated the Eagles as the home team as a way of recognising the dominance of higher ranked teams facing lower ranked teams in Finals.

Across all Finals since 2000, higher ranked teams have a 103 and 40 record against lower ranked teams, though I should note, to argue against myself a bit, that their record is only 7 and 8 in Grand Finals, as you can see from the table at right.

What's also apparent from this table though is that teams finishing 2nd have a better overall GF record than teams finishing 3rd - but that the superior record has come from their performances against teams finishing 1st or 4th, and not 3rd.

In all, I think you could make a case either way for treating the Eagles as the home team or the away team, but in the end I've gone for treating them as the home team, where that matters. Regardless of this decision, the Hawks will still be recognised by all models as enjoying the Interstate Status advantage, and their superior Venue Experience (10 games at the MCG in the last 12 months versus the Eagles' 1) will also be taken into account by those models that use this variable.

Perhaps the most important implication of treating the Eagles as the home team is that the two Funds are constrained to considering wagers on them alone. 

And, even at a head-to-head price of $2.40 and with 9.5 points start, neither Fund is interested. As we'll see below, the Head-to-Head Fund wouldn't be interested in the Eagles at any price less than about $3.75, and the Line Fund rates the Eagles as just 23% chances of prevailing in the line market given the start they've been granted.

TIPS AND PREDICTIONS

Combo_NN1 stands alone this week amongst the Head-to-Head Tipsters in its support for the underdog Eagles, a successful prediction able to elevate it to a share of 5th on the final MoS Leaderboard, and an unsuccessful prediction dropping it to a share of 7th. No other Tipster is capable of moving places.

Should the Hawks be successful on Saturday, C_Marg will finish the season with a remarkable 149 from 206 (72.3%), some four tips ahead of any other MoS Tipster, and six tips ahead of Bookie Knows Best. If we were exclude the first six rounds of the season, which is typically the portion that I set aside for model calibration, C_Marg has a 77% record, and if we start the clock in Round 15 that percentage rises to 79%. BKB's accuracy for those same subsets of games is 70% (ignoring the first six rounds), and 69% (from Round 15 onwards). It, truly, has been an exceptional season for C_Marg.

In fact, C_Marg has also done well amongst the Margin Predictors where it leads all-comers by 139 points. This week it's predicting one of the largest victory margins for the Hawks, 16 points, it having its own rules about how home ground status is determined (it uses the team with the higher ChiPS Rating, which is Hawthorn).

Here too, only Combo_NN1 is tipping against the Hawks, though it foresees the narrowest of Eagles wins. - actually, rounded, Combo_NN1 is tipping a draw.

Combo_NN2 is also, rounded, tipping a draw, though it lands even more narrowly on the other side of zero and predicts a Hawks win by one-twentieth of a behind.

None of the Predictors can see a sizable Hawks victory, nine tipping a Hawks win by between two and three goals, five more a Hawks win by between one and two goals, and four a victory by less than a goal.

The all-Predictor average result is a Hawks win by 9.5 points (curiously, exactly the start the Eagles are receiving in the line market), the range of predictions covering just 17 points, and the Mean Absolute Deviation (MAD) coming in at only 4.7 points per Predictor.

In short, overall the Margin Predictors expect the Hawks to win, but only by a short half-beak..

The H2H family of Margin Predictors are amongst those predicting the largest Hawks victories, this view reflected in the H2H Head-to-Head Probability Predictors.

They rate the Eagles as just 27% chances of snatching the Flag, this estimate much lower than the 40% chances assigned by the Bookie trio, and the 33% chance assigned by C_Prob. WinPred and ProPred, however, are of a mind similar to the H2H Predictors, rating the Eagles as about 28 to 29% chances.

Given those asssessments, no result this weekend can topple C_Prob from 1st place on the MoS Leaderboard. Bookie-RE, however, will move past Bookie-OE into 2nd should Hawthorn win. No other movements of Predictors will take place, regardless of the outcome.

For its final prediction of the year, the Line Fund algorithm has made its boldest call of the season, rating the Hawks as 77% likely to prevail in the line market. In the light of this season's Line Fund history, may I suggest that you make of that what you will.