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2017 - Round 21 : The Keys to the Finals

Expected victory margins are a little higher this week, though still at historically low levels. You really do have to keep reminding yourself just how extraordinarily even this season has been. (I should write an article about that ...)

Six of the games are expected to be won by less than 20 points, and only the Sydney v Fremantle game by more than 6 goals.

For once though, we're seeing some disagreement amongst the Head-to-Head Tipsters, with at least two dissenting voices in four of the nine contests (and that even excluding Home Sweet Home).

In two games we've a 5-4 split, with GWS having the narrow majority over the Western Bulldogs, and the Brisbane Lions likewise over Gold Coast.

The Melbourne v St Kilda game sees both MoS Tipsters siding with the underdog Saints, and the Geelong v Richmond game has the underdog Cats with a 7-2 majority.

Overall, the Disagreement Index for the round has come in at 23%, which is the highest it's been since Round 16 and 3% points above the all-season average.

It's a curious mix of conformity and contrarianism amongst the Margin Predictors, with all but C_Marg and the two MoSs broadly agreeing and returning mean absolute deviations (MADs) of between 1.5 and 3.5 points per game.

Amongst the mavericks, it isn't C_Marg defining the limits this week but instead the two MoSs who have both recorded MADs well above their season averages.

That makes for the possibility of some larger-than-normal movements on the Leaderboard for MoSHBODS_Marg this week. It now leads the two RSMP Predictors by about 10 to 12 points, and will see those leads change depending on the outcomes of each game roughly as follows:

  • Increase by 8 points over the RSMP Predictors if the Western Bulldogs win by 3 points or more
  • Increase by 7 points over the RSMP Predictors if Geelong win by 12 points or more
  • Increase by 21 points over the RSMP Predictors if the Brisbane Lions win by 18 points or more
  • Increase by 5 points over the RSMP Predictors if Adelaide win by 21 points or more
  • Increase by 11 points over the RSMP Predictors if West Coast win by 28 points or less
  • Increase by 7 points over the RSMP Predictors if St Kilda win or draw
  • Increase by 5 points over the RSMP Predictors if Hawthorn win by 20 points or less
  • Increase by 13 points over the RSMP Predictors if Port Adelaide win by 6 points or less

Four games this week carry a MAD of greater than 4 points per Predictor, but none greater than 4.3 points per Predictor. That, highest value comes in the Brisbane Lions v Gold Coast game where the forecasts span only a 4-goal range. The average span this week is about 3 goals.

The Head-to-Head Probability Predictors have an Overall MAD for the round of 4.5% points per Predictor per game, which is just slightly above the value in Round 20.

It's the Melbourne v St Kilda game that has the highest MAD of 6.6% points per Predictor, driven up by the 68% estimate of C_Prob and the 42% estimate of MoSSBODS_Prob.

MoSSBODS_Prob has the round's highest MAD (6.4% points per game), ahead of MoSHBODS_Prob (5.8% points per game), and then C_Prob (4.8% points per game).

MoSHBODS_Prob, our current leader, would be hurt most by Sydney, Geelong or Brisbane Lions losses, or by a Port Adelaide win.

WAGERS

With the high levels of contrarianism on display from the two MoS' this week, it's no surprise that Investors are facing high levels of activity.

There are six head-to-head bets totalling 15% of that Fund, and seven line bets totalling 9% of that Fund, which means that 6.6% of original Combined Portfolio funds are in play, the highest one round total since Round 11

There's upside and downside all over the place this week, with about 1% or more of upside unlocked by wins from the Western Bulldogs, Geelong, St Kilda, the Kangaroos or Collingwood, or with a 1 to 3 point win by the Brisbane Lions.

That unusual requirement in the Lions' game comes about because Investors have a head-to-head bet on the Lions thanks to MoSHBODS, and a line bet on the Suns thanks to MoSSBODS. All things considered, it's surprising we haven't had this situation arise more often this season.

Those same teams are also responsible for the majority of the downside, St Kilda, the Western Bulldogs, and the Kangaroos most of all. Together they're responsible for more than half the aggregate downside, which this week totals 6.2%.

MoSSBODS AND MoSHBODS

Here are the MoS twins' views on team and total scoring for the week.

Commentary to follow.