Matter of Stats

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2018 - Round 13 : Overs/Unders Update

If the bookmakers are right, not a single game should be expected to generate more than 168 points over this elongated in time and truncated in content weekend of football.

MoSSBODS offers slightly more hope in its forecast of a 172 point total for the Suns v Saints game but, for the most part, the MoS twins concur with the bookmakers about the likely dearth of scoring this week. We should expect an all-game average of 160 points per game or less.

Again this week there are high levels of agreement across the four forecasters about the likely high- and low-scoring teams and games, though there is some debate about how high and how low.

MOST LIKELY HIGH-SCORING GAME

  • All : Gold Coast v St Kilda (167.5 to 172)

MOST LIKELY LOW-SCORING GAME

  • All : Port Adelaide v Western Bulldogs (140.5 to 151)

MOST LIKELY HIGH-SCORING TEAM

  • MoSSBODS & MoSHBODS : St Kilda (93 to 98)
  • TAB : Port Adelaide and St Kilda (88)
  • Centrebet : Port Adelaide (90)

MOST LIKELY LOW-SCORING TEAM

  • All : Western Bulldogs (52.5 to 59)

MoSHBODS did well in forecasting the extremes of team and game scoring last weekend, with its top picks for low- and high-scoring team, and for low-scoring game all proving accurate, and its second choice for high-scoring game ultimately being the right one.

Over the course of the season, however, it's still done worse than a naive forecaster in estimating probabilities for the high- and low-scoring games, and better than a naive forecaster in estimating probabilities for the high- and low-scoring teams.

This week, MoSHBODS has St Kilda as the likely high-scoring team, and the Western Bulldogs (by some margin) as the likely low-scoring team.

The Suns v Saints game is estimated as being most-likely to be the round's high-scoring game, with an estimated probability of just under 25%, while the Power v Dogs games is estimating as having a slightly higher probability of being the round's low-scoring game.

WAGERS

Just two wagers this week, both overs, and in the round's first and last games.

The forecast for both Thursday night's and Sunday afternoon's game is for showers. If they eventuate, this will narrow our current estimated overlay of about 10 points.

PERFORMANCE TO DATE

Last week was another poor one for MoSSBODS and MoSHBODS in terms of the totals markets, with MoSSBODS on the correct side of the TAB's and Centrebet's totals in only one of the seven games, and MoSHBODS on the correct side of the TAB's in one and Centrebet's in two.

That gives MoSSBODS a season-long 50% record against the TAB and Centrebet, and gives MoSHBODS a 49% record against the TAB and a 52% record against Centrebet.

MoSSBODS' record continues to be starkly different for overs as compared to unders wagers. Across the two bookmakers it now has a 28% strike rate on overs bets, and a 63% strike rate on unders bets.

That doesn't augur well for this week ... 

On the mean absolute error (MAE) metric, it was a triumphant week for the TAB bookmaker. He registered the lowest MAE for game margins, away team scores, and game totals, leaving Centrebet to take the honour for home team scores. 

Centrebet still leads, however, on the season-long view for home team scores, as does MoSHBODS on team scores, and the TAB on game margins. Centrebet also, however, took top spot away from MoSHBODS on game totals.