Tag: Analysis

  • Flying Blind: Why This Model Ignores the Betting Markets

    The Dirty Secret of Most Prediction Models

    Here’s something that doesn’t get talked about enough: a lot of “prediction models” you see floating around aren’t really predicting anything. They’re laundering the betting market’s opinion through a spreadsheet and calling it analysis.

    The market opens on Monday morning. Punters pile in. The odds shift. The model ingests those odds as a feature. The model now “predicts” something very close to what the market already said. Everyone goes home feeling clever.

    This model doesn’t do that.


    What the Markets Know (A Lot)

    To be clear: the betting markets are genuinely impressive. They aggregate information from thousands of punters, professional analysts, injury tipsters, and people who probably have a guy inside the club. The line moves fast when a key player gets a late scratch. It adjusts for weather, travel, and the specific psychological state of teams coming off a big win or a demoralising loss.

    Markets are efficient in the way that makes economists happy. They’re not perfect, but they’re rarely stupid.

    So yes — ignoring them has a cost. A model that uses market odds as an input will almost certainly be more accurate than one that doesn’t, all else being equal. The market knows things this model doesn’t. That’s just true, and pretending otherwise would be dishonest.


    So Why Not Just Use Them?

    Because that’s not the question I’m trying to answer.

    If I wanted to know who was most likely to win a given game, I’d look at the odds. Done. No model required. The markets have already done the hard work, pooled vast amounts of information, and distilled it into a probability. It’s probably pretty close.

    What I’m actually interested in is: what does the football tell us? Not what the market thinks, not what the punting public thinks — what do the underlying statistics of how teams have actually been playing suggest about what’s likely to happen next?

    That’s a different question, and it requires a model that’s genuinely blind to market opinion.


    The Philosophy (Bear With Me)

    Think of it this way. You can build a model that predicts temperature using a weather forecast as an input. It will be highly accurate. It will also be completely useless as a scientific instrument, because all it’s doing is repeating someone else’s forecast back at you.

    Or you can build a model that predicts temperature using atmospheric pressure, humidity, historical patterns, and satellite imagery — no forecast allowed. It might be less accurate in the short run. But it’s actually doing something. It’s making independent claims about the world based on underlying signals, not just echoing consensus.

    This model is the second kind. It looks at how teams have been moving the ball, how their players have been performing, who’s travelling interstate, who’s got an inexperienced lineup. It doesn’t know what Tab.com.au thinks about any of it.

    That means when it disagrees with the market, it’s a genuine disagreement — not noise.


    The Advantage: Finding the Market’s Blind Spots

    Because this model forms its opinions independently, it occasionally sees things the market doesn’t weight heavily enough.

    Travel is a good example. The market prices in some interstate disadvantage, but it’s a blunt adjustment. This model calculates actual travel distances and applies a penalty based on historical evidence. Sometimes that surfaces something the odds haven’t fully captured.

    Player experience is another. When a team’s lineup is unusually young — a lot of players under 50 games — the model applies an inexperience penalty based on rolling individual game counts. Markets probably notice the obvious cases (a team suddenly fielding four rookies), but the subtler version of this effect tends to get washed out in the noise.

    The model’s opinion is formed entirely from what happened on the field, over the last handful of weeks. If the market is pricing something else — reputation, interstate crowd size, the narrative around a particular coach — then the model is ignoring all of that. Which is either a bug or a feature depending on what the market has gotten wrong lately.


    The Honest Part

    This approach comes with real costs, and it would be silly to pretend otherwise.

    Late team changes — particularly the Thursday night selections that get announced after the TAB has already adjusted — mean the model is sometimes working with outdated lineup information. The market has already moved. This model is still thinking about last week’s 22. Run make lineups and make predict after selection Thursday and that narrows the gap, but it doesn’t close it entirely.

    There’s also a deeper issue: some things that predict football outcomes aren’t cleanly measurable in statistics. Team morale. Player confidence. A coach who’s about to get sacked. The market absorbs some of that. This model, emphatically, does not.

    So when the model and the market disagree, there are two possibilities: either the model has found something the market missed, or the market knows something the model doesn’t. Both happen. The trick is figuring out which.


    The Bottom Line

    Most tipping models are glorified odds converters. This one is trying to do something different — build an independent view of what the football says, without peeking at the consensus.

    That makes it less accurate in absolute terms than a model that just launders market opinion. It also makes it more interesting. When it’s right despite disagreeing with the market, that’s a genuine signal. When it’s wrong, at least you know it failed on its own terms, not because it was following someone else’s homework.

    Flying blind has costs. But it also keeps the lights on.

  • Under the Hood: Model Improvements for 2026

    A Better Picture of Form

    Going into 2026, I’ve made the most significant changes to the prediction model since the site launched. The short version: the model now has a better sense of how teams have been playing, not just whether they’ve been winning.

    Previously, the main form signals came from things like recent win rates, scoring margins, and player quality (measured through fantasy scoring). These are solid indicators, but they miss something. A team can win a few scrappy games and look fine on paper while actually playing pretty poor football — and vice versa. A team can lose a close game while dominating possession and territory.

    The new version of the model picks up on some of those subtler signals.


    What’s New

    How far teams move the ball. One of the new inputs tracks how much territory a team’s players gain with the ball in hand — not just whether they’re taking possessions, but whether those possessions are actually advancing the team forward. A team that consistently pushes the play into attacking positions tends to create more scoring opportunities, and the model now accounts for that.

    How often teams are involved in scores. This measures how many players in a team’s lineup are regularly contributing to scoring chains — the sequences of kicks and handballs that lead directly to a goal or behind. It’s a sign of a team playing connected, structured football rather than relying on individuals to do everything.

    Quality of ball use. Two sides of the same coin: how often players use the ball effectively, and how often they give it straight back to the opposition through poor decisions. Raw disposal counts have always been in the model, but this new layer separates the clean, purposeful ball use from the messy stuff.


    Why It Matters

    All four of these measures are calculated as rolling averages across each team’s last six games, then compared against the opposing team. A large gap in any of these areas tends to be a meaningful predictor of the result — more so than the raw score from last week.

    The model still uses all the same signals it always has (recent wins and margins, player experience, travel disadvantage, scoring shot rates). The new features sit alongside them, giving a fuller picture.


    A Note on the Numbers

    Test accuracy on historical data came in at 69.4% with the new model — a solid improvement over previous versions. That figure comes from games the model had never seen during training, so it’s a genuine out-of-sample measure rather than a self-congratulatory one.

    For the top 30% of predictions where the model is most confident, historical accuracy is considerably higher. Those are the picks worth paying most attention to.


    Round 1 predictions are coming. The new model has Opening Round data to work with, so it’s already picking up on how teams looked in the first week back.

  • Opening Round 2026 Preview

    Welcome to 2026

    The AFL season is back, and so are the predictions. This week I’m running the model over Opening Round — five games, no second chances to make a first impression.

    The Marquee Game: Collingwood vs St Kilda at the MCG

    The model’s most confident call this round. Collingwood have strong fantasy scoring and disposal form heading into the game, while St Kilda’s metrics are below average. The MCG gives Collingwood an additional edge. 72% confidence — this is one to trust.

    Sydney vs Carlton at the SCG

    The model’s second most confident call. Carlton’s away travel is a significant factor, and Sydney’s disposal and form metrics are strong at home. The model gives Sydney a clear edge at 70/30 — this is a high confidence pick.

    Geelong vs Gold Coast at People First Stadium

    Geelong travelling north but the model still likes them at 59%. Their average margin and fantasy scoring are both strong coming off the 2025 Grand Final campaign. Gold Coast have decent recent wins but the quality gap shows in the numbers.

    GWS vs Hawthorn at ENGIE Stadium

    GWS at home is a decent advantage. The model calls this 56/44 GWS. Hawthorn are travelling but have reasonable form — worth watching if you’re looking for an upset.

    Brisbane Lions vs Western Bulldogs at the Gabba

    Brisbane at the Gabba is a stronghold. 55% model confidence, with Brisbane’s average margin being the key differentiating factor. The Bulldogs have interstate travel working against them.

    Summary

    Match Model Pick Confidence
    Sydney vs Carlton Sydney High (70%)
    Gold Coast vs Geelong Geelong Medium (60%)
    GWS vs Hawthorn GWS Low (56%)
    Brisbane vs W. Bulldogs Brisbane Low (55%)
    St Kilda vs Collingwood Collingwood High (72%)

    Two high-confidence calls this round: Collingwood and Sydney. For the rest, I’d be cautious — Opening Round always throws up surprises.