2018 - Round 20 : Overs/Unders Update

Another week, another sub-170 point average total score expectation, though this week we can maybe hope that four games will exceed that threshold.

Not, however, if we favour the MoS twins over the bookmakers since they have only two contests breaching the 170 point high watermark. As a result, their average expected score is a couple of points lower than the bookmakers', due to a combination of slightly lower scoring expectations for home teams and slightly lower scoring expectations for away teams. Their average home team margin, though, is about the same as the bookmakers'.

In fact, they agree with the bookmakers about quite a bit this weekend.

MOST LIKELY HIGH-SCORING GAME

  • MoSSBODS: Melbourne v Gold Coast (181)
  • MoSHBODS, TAB & Centrebet: Brisbane Lions v Kangaroos (180 to 186.5)

MOST LIKELY LOW-SCORING GAME

  • All: Adelaide v Port Adelaide (151.5 to 157)

MOST LIKELY HIGH-SCORING TEAM

  • All: Melbourne (113 to 121)

MOST LIKELY LOW-SCORING TEAM

  • All: Gold Coast (53.5 to 63)

MoSHBODS' performance was outstanding last weekend. It attached its highest probabilities to each of the high- and low-scoring teams and games. Specifically, it attached:

  • 18.3% probability to the highest-scoring team, Geelong (against a naive forecast of 5.6% since 18 teams were playing)
  • 13.9% probability to the lowest-scoring team, Western Bulldogs (against a naive forecast of 5.6%)
  • 15.6% probability to the highest-scoring game, Geelong v Brisbane Lions (against a naive forecast of 11.1% since 9 games were played)
  • 22.0% probability to the lowest-scoring game, Western Bulldogs v Port Adelaide (against a naive forecast of 11.1% since 9 games were played)

This week, MoSHBODS has

  • five teams as more likely than 1 in 18 to be the highest-scoring: Melbourne, GWS, Richmond, West Coast, and Brisbane Lions
  • four teams as more likely than 1 in 18 to be the lowest-scoring: Carlton, Fremantle, Gold Coast, and Geelong.
  • two games as more likely than 1 in 9 to be the highest-scoring: Lions v Roos, and Dees v Suns.
  • four games as more likely than 1 in 9 to be the lowest-scoring: Crows v Power, Eagles v Dockers, Blues v Giants, and Swans v Pies.

WAGERS

Investors have six wagers this week, four unders and two overs bets.

The relevant weather forecasts are as follows:

  • Richmond v Geelong (MCG - overs bet): Rain developing. 80% chance of rain.
  • Hawthorn v Essendon (MCG - unders bet): Cloudy. 10% chance of rain.
  • Brisbane Lions v Kangaroos (Gabba - unders bet): Sunny. 5% chance of rain.
  • Carlton v GWS (Docklands - unders bet): Shower or two with chance of roof.
  • Melbourne v Gold Coast (MCG - overs bet): Shower or two. Windy. 70% chance of rain.
  • West Coast v Fremantle (Perth Stadium - unders bet): Partly cloudy. 20% chance of rain.

In a more perfect universe you'd not arrange for 70 to 80% chance of rain at the venue for your overs bets, especially when your estimated rain-free overlays are 10 points or less, but it is what it is.

PERFORMANCE TO DATE

It was another week of quite different performances from the MoS twins', with MoSSBODS finishing on the right side of TAB totals in five games, and the right side of Centrebet totals in four, while MoSHBODS managed only two against the TAB and just one against Centrebet.

That left MoSSBODS' with a season-long 49% record against the TAB and a 48% record against Centrebet, and left MoSHBODS with a 48% record against the TAB and a 50% record against Centrebet. 

MoSSBODS' landed 0 of 2 overs bets with the TAB, 0 of 1 overs bets with Centrebet, and 1 of 1 unders bets with Centrebet last weekend. That left its overall strike rate on overs bets at 29% and dropped its overall strike rate on unders bets to 59%.

On the mean absolute error (MAE) metric, MoSHBODS registered the lowest MAE for game margins and home team scores, Centrebet registered the lowest MAE on away team scores, and the two bookmakers tied for lowest MAE on game totals.

Centrebet still leads on the season-long view for home team scores (MAE of 17.7) and for game margins (26.9), but remains tied with the TAB for game margins (22.4). The TAB still leads on away team scores (17.6).