2023 - Round 11 : Overs/Unders

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Overall, the MoS twins have roughly the same expectations about likely average total scoring in Round 11, although there are a few sizeable differences of opinion about individual games.

As highests and lowests, we have:

HIGHEST SCORING GAME

  • MoS twins: West Coast v Essendon

  • Bookmakers: Geelong v GWS

LOWEST SCORING GAME

  • MoS twins: St Kilda v Hawthorn

  • Bookmakers: Gold Coast v Western Bulldogs

HIGHEST SCORING TEAM

  • MoS twins: Geelong

  • Bookmakers: Essendon

LOWEST SCORING TEAM

  • All: North Melbourne

WAGERS

Investors have three wagers this week, two unders and one over.

In the St Kilda v Hawthorn the two markets were

  • TAB u162.5 $1.85

  • Sportsbet u161.5 $1.88

In essence, I’ve paid 3c for an extra point. If we assume that Game Totals are distributed as a Normal about their expected value (which, empirically, seems reasonable) and that the standard deviation (SD) of that Normal is about 30 points (again historically reasonable), and if we assume that the Sportsbet Total is correct, we have:

For the TAB: EV = 1.85 * NORMDIST(162.5 - 161.5, 30, TRUE) = 0.95

For Sportsbet: EV = 1.88 * NORMDIST(161.5 - 161.5, 30, TRUE) = 0.94

So, the TAB bet would offer a higher expected value.

But, if we instead assume that MoSSBODS’ Total of 145 points is correct, we have:

For the TAB: EV = 1.85 * NORMDIST(162.5 - 145, 30, TRUE) = 1.3323

For Sportsbet: EV = 1.88 * NORMDIST(161.5 - 145, 30, TRUE) = 1.3326

Here, the Sportsbet bet offers a fractionally higher expected value.

(Note that, by convention, I convert a $1.85 price into a one point adjustment for the purposes of the table below. The correct adjustment depends on what assumption we make about the SD and how far away the adjustment is made from the true expected Total)

The estimated overlays for the games where we’ve a wager are all between 10.5 and 16 points.

PREVIOUS RESULTS

Honours for the lowest Mean Absolute Errors (MAEs) this week were again shared around, with MoSSBODS taking Away Team Scores, MoSHBODS taking Game Totals, the TAB taking Game Margins, and Sportsbet taking Home Team Scores.

MoSHBODS still has the season-best MAE for Away Team Scores, the TAB Bookmaker still has season-best for Game Margins and Home Team Scores, while the Sportsbet bookmaker now has outright season-best for Game Totals.

The leads are as follows:

Game Margins: TAB 10.9 points ahead of MoSHBODS and 23.9 points ahead of MoSSBODS

Home Team Scores: TAB 8.5 points ahead of Sportsbet, and 73.5 points ahead of MoSHBODS

Away Team Scores: MoSHBODS 1.5 points ahead of MoSSBODS, and 17.5 points ahead of the TAB

Game Totals: Sportsbet 4 points ahead of the TAB, and 10.6 points ahead of MoSHBODS

MoSSBODS had four wagers last week, two unders wagers with the TAB, and two unders wagers with Sportsbet. It won both wagers with the TAB (although this is erroneously recorded as a 1 from 2 outcome on the weekly summary, which will be corrected this week), and it lost both wagers with Sportsbet.

Overall, its season record stands at 13 wins and 13 losses.

Across all games, the MoS twins recorded 5 from 9 results against the TAB, and 4 from 9 results against Sportsbet.

That moved MoSSBODS to a 43 from 90 (48%) record against the TAB, and a 41 from 90 (46% ) record against Sportsbet. MoSHBODS now has a 47 from 90 (52%) record against the TAB, and a 47 from 90 (52%) record against Sportsbet.

TEAM SCORE FORECAST ERRORS

It’s interesting to look at which teams’ scores have been hardest to forecast so far this season.

In raw scoring terms:

  • West Coast, Geelong, Sydney, North Melbourne, Fremantle, and GWS have all tended to score more points than the forecasters have expected

  • Collingwood, Western Bulldogs, St Kilda, Gold Coast, Richmond, and Adelaide have all tended to score fewer points than the forecasters have expected

In mean absolute error terms:

  • GWS, Adelaide, Melbourne, and Essendon have been easiest to forecast

  • Sydney, Geelong, Gold Coast, and Hawthorn have been hardest to forecast