The 2014 Grand Final : When the Coin Flipped

/

The Sydney Swans were deserved pre-game favourites on Saturday according to most pundits (but not all - congratulations to Robert and Craig for tipping the winners). At some point during the course of their record-breaking loss that favouritism was handed to the Hawks. In this blog we'll investigate when.

Read More

Modelling Game Outcomes In-Running

/

Way back in 2010 I developed a model to estimate the Home team's chances of victory in-running (ie during the course of a game) based on the lead it held at the time and the time remaining in the game. In a subsequent post I investigated ways of combining the in-running projections of that model with the TAB Bookmaker's pre-game assessments in something of a proto-Bayesian way.

Read More

The Ten Most Surprising Things I've Learned About AFL So Far

/

The last few months have been a generally reflective time for me, and with my decision to leave unchanged the core of MAFL algorithms for 2014 I've been focussing some of that reflection on the eight full seasons I've now spent analysing and predicting AFL results.

Read More

To Win A Grand Final You Must First Lead

/
History suggests that, as the higher-Rated "Home" team, Hawthorn must lead early and lead well if it is to be confident of success in Saturday's Grand Final, and not assume that its superior Rating will allow it to come back from any substantial deficit.
Read More

In-Running Models: Confidence Intervals for Probability Estimates

/
In a previous blog on the in-running models I generated point estimates for the Home team's victory probability at different stages in the game under a variety of different lead scenarios. In this blog I'll review the level of confidence we should have in some of those forecasts. More formally, I'll generate 95% confidence intervals for some of those point forecasts.
Read More

Characterising AFL Seasons

/
I can think of a number of ways that an AFL season might be characterised but for today's blog I'm going to call on a modelling approach that I used back in 2010, which is based on Brownian motion and which was inspired by a JASA paper from Hal S Stern.
Read More

Predicting the Final SuperMargin Bucket In-Running

/
On Friday night, while watching the progress of the Saints v Freo game knowing that Investors has a SuperMargin wager on the Saints to win by 20-29, I was wondering how to react to the changes in the scoreline as the game progressed. Should I want the Saints to lead early? By a little? By a lot? By about 5 points at Quarter Time and 10 points at Half Time?
Read More

Predicting the Final Margin In-Running (and Does Momentum Exist)?

/
Just a short post tonight while we wait for the serious footy to begin. For this blog I've again called upon the services of Formulize, this time to find for me equations that predict the final victory margin for the Home team (which might be negative or zero) purely as a function of the scores at the various quarter breaks.
Read More

Projecting the Favourite's Final Margin

/
In a couple of earlier blogs I created binary logit models to predict the probability that the favourite would win given a specified lead at a quarter break and the bookmaker's assessed pre-game probability for the favourite. These models allow you to determine what a fair in-running price would be for the favourite. You might instead want to know what the favourite's projected victory margin is given the same input data, so in this blog I'll be providing some simple linear regressions that provide this information.
Read More

An Empirical Review of the Favourite In-Running Model

/
In the previous blog we reviewed a series of binary logits that modelled a favourite's probability of victory given its pre-game bookmaker-assessed head-to-head probability and its lead at the end of a particular quarter. There I provided just a single indication of the quality of those models: the accuracy with which they correctly predicted the final result of the game. That's a crude and very broad measure. In this blog we'll take a closer look at the empirical model fits to investigate their performance in games with different leads and probabilities.
Read More

Hanging Onto a Favourite: Assessing a Favourite's In-Running Chances of Victory

/
Over the weekend I was paying particular attention to the in-running odds being offered on various games and remain convinced that punters overestimate the probability of the favourite ultimately winning, especially when the favourite trails.
Read More

Drawing On Hindsight

/
When sports journos wait until after a contest has been decided before declaring a group of winning punters to be "savvy", I find it hard not to be at least a little cynical about the aptness of the label.

So when, on Sunday, I read in the online version of the SMH that a posse of said savvy punters had foxed the bookies and cleaned up on the draw, collectively winning as I recall about $1m at prices ranging from $34 to $51, I did wonder how many column-inches would have been devoted to those same punters had the margin been anything different when the final siren sounded on Saturday. I'm fairly certain it would have been the number that has '1' as its next-door, up the road neighbour on Integer Street.
Read More

In-Running Wagering: What's the Best Strategy?

/
With services such as Betfair now offering in-running wagering opportunities, the ability to accurately assess a team's chances of victory at any given point in a game is now of considerable commercial value. Imagine, for example, that your team, who are at home, lead by 18 points at the first change. Would a wager on them at $1.40 be advised?
Read More