Matter of Stats

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2018 - Round 17 : Overs/Unders Update

Another weekend of relatively low scores seems to be in prospect, with only one or perhaps two games likely to see over 170 points scored, and only one or two teams likely to register three-digit scores.

In aggregate, all four forecasters are suggesting an all-game average in the mid 160s, which would bring it in at roughly the season-average figure. That historically low average of just 165.4 points per game continues to be driven both by historically low scoring shot generation and historically low scoring shot conversion.

The last time a full season passed with a lower average was 1968 when it finished as 164.1 points per game. In that season, about 3 extra scoring shots were generated per game, on average, compared to 2018, so the lower scoring was attributable solely to lower scoring shot conversion.

Anyway, back to this week, where we find the forecasters views about high- and low-scoring teams and games as follows:

MOST LIKELY HIGH-SCORING GAME

  • MoSSBODS and TAB : Melbourne v Western Bulldogs (175 to 178)
  • MoSHBODS and Centrebet : Hawthorn v Brisbane Lions (180.5)

MOST LIKELY LOW-SCORING GAME

  • All : Fremantle v Port Adelaide (151.5 to 154.5)

MOST LIKELY HIGH-SCORING TEAM

  • All : Melbourne (102 to 109)

MOST LIKELY LOW-SCORING TEAM

  • MoSSBODS, MoSHBODS and TAB : Fremantle (64 to 67)
  • Centrebet : Gold Coast (63.5)

MoSHBODS did mostly poorly relative to naive forecasting in selecting the extremes of team and game scoring last weekend, attaching:

  • 3.6% probability to the highest-scoring team, Hawthorn (against a naive forecast of 5.6% since 18 teams were playing)
  • 5.5% probability to the lowest-scoring team, Fremantle (against a naive forecast of 5.6%)
  • 6.3% probability to the highest-scoring game, Western Bulldogs v Hawthorn (against a naive forecast of 11.1% since 9 games were played)
  • 19.8% probability to the lowest-scoring game, Sydney v Geelong (against a naive forecast of 11.1% since 9 games were played)

This week, MoSHBODS has

  • seven teams as more likely than 1 in 18 to be the highest-scoring: Melbourne, Hawthorn, Essendon, St Kilda, Richmond, and Geelong.
  • eight teams as more likely than 1 in 18 to be the lowest-scoring: Fremantle, GWS, Carlton, Gold Coast, Brisbane Lions, Adelaide, Western Bulldogs, and West Coast.
  • three games as more likely than 1 in 9 to be the highest-scoring: Dees v Dogs, Hawks v Lions, and Suns v Dons.
  • four games as more likely than 1 in 9 to be the lowest-scoring: Dockers v Power, Roos v Swans, Crows v Cats, and Giants v Tigers.

WAGERS

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

The current weather forecasts for both of the overs bets are encouraging: "partly cloudy" for the Thursday game at the Adelaide Oval, and "sunny" for the Saturday game at Carrara. For the unders bet on Saturday, where the game is at York Park, the forecast is also "sunny".

Overlays for the three games range from 8.5 to 14.7 points.

Given the recent performance of the Overs/Unders Fund, excuse me if I refrain from opining about whether, based on all that commentary, the prospects for these three wagers are good or bad.

PERFORMANCE TO DATE

MoSSBODS finished on the correct side of the TAB's and Centrebet's totals in four of the nine games last weekend, which is exactly the same performance that MoSHBODS recorded.

That left MoSSBODS' with a season-long 49% record against the TAB and a 48% record against Centrebet, and left MoSHBODS with a 47% record against the TAB and a 50% record against Centrebet. They all remain depressingly close to coin-toss type records.

MoSSBODS' landed 0 of 1 overs bets with the TAB and with Centrebet last weekend, as well as 1 of 2 unders bets with Centrebet. Its overall strike rate on overs bets is now 27% and on unders bets 60%.

On the mean absolute error (MAE) metric, MoSSBODS registered the lowest MAE for home team scores, the TAB for game totals, and Centrebet for game margins, while the TAB and Centrebet shared joint-low for away team scores.

Centrebet still leads on the season-long view for home team scores and game totals, while the TAB still leads on game margins and away team scores.