2015 - Round 19 : A Cautious Re-Entry

I probably should have reminded Investors at the back end of last week's paltry profit that we would, as published protocol insists, be ratcheting back line bets this week as we come out of the period where, historically, the Line Fund has been at its most profitable, but I suspect some subliminal irony shield may have deployed and protected me from providing this reminder. In any case, Investors please note that line bets have been halved this week, as per previous advisement.

As a consequence, our three Line wagers carry downside (and upside) only 50% as large as they would have been had the same bets been placed last weekend.

Those three line wagers are split, two on favourites and one on an underdog, and are accompanied by a single head-to-head bet on one of those same favourites, the Dogs, priced at $1.75 in the head-to-head market (and giving 4.5 points start in the line market).

This week then, a full Ready Reckoner is perhaps in order, albeit that the profit/loss line in six games reflects nothing but inactivity.

So it is that Investors find themselves most invested in a Dogs win by 5 points or more, which would add over 2c to the value of the Overall Portfolio, and most concerned about the Dogs' failing to honour that contract, which would strip 2.4c off the value of that Portfolio.

In other games, both the Lions and GWS have the ability to knock 1.5c off the value of the Overall Portfolio by declining the opportunity to prevail on line betting, yet also have the ability to add 1.4c should they opt to deliver against our preferences.

Aggregated, these wagers are capable of adding about 4.8c to the value of the Overall Portfolio, and also capable of stripping 5.4c off the that value.

HEAD-TO-HEAD TIPSTERS

This week sees a return to slightly more normal levels of disagreement amongst the Head-to-Head Tipsters, the all-Tipster average Disagreement Index of 21% the 13th-highest this season.

Home Sweet Home's 59% defines the upper bound of anarchy, though it's not all that much higher than Easily Impressed II's 58%, and only somewhat greater than Short Term Memory II's 39% and Shadow's 38%.

The all-Tipster Disagreement Index has been tempered by the 17 Tipsters whose Index has come in at just 14%, amongst them the Top 4 Tipsters on the MoS Leaderboard.

With those Top 4 Tipsters selecting the nine favourites, we'll see no change in the ordering of this quartet. Directly below them, however, C_Marg and Combo_NN2 have shown some independence of thought and so will profit if, in C_Marg's case, Geelong surprises Sydney and if, in Combo_NN2's case, Port Adelaide surprises the Western Bulldogs.

Looking from a game-by-game perspective we find this week that no game has elicited unanimity, though six favourites have garnered support from all but, at most, two Tipsters.

In the three remaining games we have between 5 and 11 Tipster support for the less-favoured teams, the low end occurring in the Crows v Tigers game where 5 Tipsters have sided with the Crows, and the high end manifesting in the Eagles v Hawks game, where 11 Tipsters have voted for a home-team Eagles win.

MARGIN PREDICTORS

This week, MoS' margin Predictors have conspired to produce the most aligned predictions of the season so far, the all-Predictor average of 3.3 points per game per Predictor some 1.6 points per game per Predictor below the previous low from Round 15. That truly is an amazing level of agreement.

That context regardless, C_Marg has still been contrarian enough to record a 9.4 points per game Mean Absolute Deviation (MAD) from the all-Predictor averages, over 3 points per game higher than the next-highest Predictor, Combo_NN2. At the other end of the disagreement scale, six Predictors - the four from the H2H family plus Combo_7 and Bookie-LPSO - have recorded MADs below 2 points per game.

C_Marg, the current competition leader, has most to lose if actual results differ most from its predictions of a 39 point Pies win, a 24 points Dogs win, a 9 point Geelong win, a 33 point Roos win, a 27 point Giants win, or a 7 point Fremantle win.

Viewing the predictions on a game-by-game basis, it's clear that the Collingwood v Carlton game has driven more than its share of dissension, the all-Predictor MAD for that game coming in at just under a goal per Predictor. Just four other contests have average MADs above 3 points per Predictor. Lowest of all is the 1.1 points per Predictor MAD in the Crows v Tigers matchup, where the entirety of the 19 predictions spans only a single goal's range.

PROBABILITY PREDICTORS

Similarly to the Margin Predictors, the Head-to-Head Probability Predictors appear to have chosen this week for a show of solidarity, the all-Predictor average MAD of 3.6% per game per Predictor the second-lowest we've seen this season, behind only the 3.5% from Round 14.

Most astonishing are the probability predictions in the Crows v Tigers game where the overall MAD is just 0.7% points per Predictor and the predictions themselves can be blanketed by a 3% point range from 42% to 45%.

The Dogs v Port game has the round's largest MAD of 4.9% points per Predictor, though those for the Cats v Swans (4.7%), Pies v Blues (4.6%), and Eagles v Hawks (4.4%) matchups are not all that much smaller.

C_Prob, unbidden but not unexpectedly, has endeavoured to drive the all-Predictor average MAD up, its 7.4% per game average MAD more than 2% points higher than the next-highest, WinPred's, at 5.1% per game. Conversely, Bookie-RE, which sits 2nd on the MoS Leaderboard, has the week's lowest MAD of 2.1%.

The Line Fund algorithm this week rates only one team, Hawthorn, as 60% chances on line betting, though it does rate six teams as 55% chances or better: Carlton (56%), Western Bulldogs (56%), Brisbane Lions (55%), Sydney (56%), GWS (58%), and Fremantle (57%).

DISAGREEMENT DATA

The latest, complete disagreement data appears in the table below, an analysis of which reveals that the correlations (on a round-by-round basis) between:

  • The Head-to-Head Tipsters' combined Disagreement Index and overall Accuracy is -0.36
  • The Margin Predictors' combined MAD and overall MAE is +0.25
  • The Head-to-Head Probability Predictors' combined MAD and overall LPS is -0.42

It remains the case then, that rounds in which the Tipsters and Predictors have disagreed least have also been the rounds in which the overall performances have been best.