AFL Prediction & Analysis

The Secret Weapon of the AFL’s Best Forward-line – Figuring Footy

Figuring Footy shows just how much extra attacking real estate a side gains when it can kick goals from further out, and looks at how effectively Adelaide are using it:

Because the ground opens out wider the further you get from goal, adding an extra 10 metres to your kicking distance does not just increase your opportunities by 20%, but rather increases the size of your “goal scoring zone” by around 43%. This is a massive increase in the area the opposition needs to defend, both from leading forwards and midfielders/backmen drifting forward.

Source: The Secret Weapon of the AFL’s Best Forward-line – Figuring Footy

Squiggle on Round 4

I’m reading “The Enchanted Wood” to my kids at the moment. In the middle of the Faraway Tree, Moon-Face has a slippery-dip that goes all the way down the inside the tree, which Joe, Beth, and Frannie ride down on cushions. Just like Hawthorn! Wheee!

But as you can tell from the flood of Richmond supporters entering this thread, the big story this week wasn’t that Hawthorn are heading for the soft moss outside the trapdoor at the bottom of the tree, nor that Geelong might actually win the flag this year, and not even that Nathan Buckley is nearing completion of his master plan to dismember one of the greatest teams in modern football. No! IT’S THAT THE TIGERS ARE 4-0.

Like every Richmond fan, I’ve spent the past 48 hours scouring the internet for anyone prepared to say we’re a premiership threat and mashing the LIKE button. I was hoping Squiggle would deliver for me here, but no, it’s still pretty tepid on the Tigers. It is tipping them to make finals for the first time, but only just, and it thinks the next month promises a return to reality, with a series of tough games.

So obviously Squiggle has SERIOUS FLAWS.

Actually, it’s for two reasons. Firstly, Squiggle doesn’t think teams get a lot better or worse in a hurry. It’s pretty conservative in this regard, because historically, teams really don’t get a lot better or worse in a hurry very often. As shocking as it is to see Hawthorn suddenly coughing up consecutive 86-point defeats, this is a team that started exhibiting symptoms of the same disease that claimed Fremantle the year before: pinching a bunch of close games and tailing off into the finals. In 2015 I wrote that Fremantle were the luckiest minor premier ever; in 2016 I wrote that in a fair universe, Hawthorn would have finished 6th, not 3rd. Most of the time, just like when Joe visits the Land of Toys and is turned into a clockwork clown, teams start hinting at what they’re becoming before they actually become it.

And the Tigers were pretty bad last year, finishing 13th with 8 wins, a percentage of 79.5, and no excuses like terrible injuries or a run of close losses. They were just bad. Admittedly, they made finals three years in a row before that, but in the worst possible way you can make finals three years in a row: the way where you don’t win any. This isn’t a premiership contender bouncing back from one dud season.

Secondly, while the Tigers have outperformed Squiggle expectations in all four matches, they’ve only done so by a few goals each time. You can move rapidly on Squiggle if you deliver (or receive) an unexpected thrashing, but the Tigers haven’t done that. They’ve just been a bit better.

So Richmond is rated a middle-ish team with four wins in the bank. Like North Melbourne last year, that looks like a club that will make finals, but not do much more. So, you know, Richmond 2013-15.

And that means that, like last year, there’s a gap between the best seven (Adelaide, GWS, Geelong, Bulldogs, West Coast, Port Adelaide, Sydney) and the rest. Just as the Tigers haven’t risen far because they’ve haven’t delivered a thrashing, Sydney haven’t fallen far because they haven’t received one. So while the Swans’ 0-4 start has virtually destroyed their hopes of a Top 4 finish, they’re probably still a very good team.

Geelong is this week’s big winner, by opening up their Top 2 chances. This is a lot more graphic in Tower of Power form:

Especially if you imagine a little regurge sound. Or produce one involuntarily. Of course, it’s possible that Hawthorn is going full Fremantle 2016 and the Cats aren’t that great; the Hawks are just that bad. After all, even Gold Coast can beat the Hawks by 86 points. But 134-48 is still impressive, particularly the 48 part, where they restrict an opposition to six goals.

It was a bad week for Brisbane, who look increasingly lonely as most of last year’s bottom 6 show improvement (Richmond, Fremantle, Gold Coast, Essendon). I mean, not Hawthorn-bad. Relative to Hawthorn, Brisbane’s week was like visiting the Land of Birthdays, where you get a wish granted with every slice of cake you eat. But still not great.

Flagpole!

Live squiggle!

Why 2017 Results Are Flattering The Cats – Figuring Footy

Figuring Footy ShotPlots are back!

One other method used by most footy fans is considering the number of scoring shots. A team leading 3 goals straight to 1.11 is probably not dominating the game to the standard they’d like. The problem with this method is that goals/behinds doesn’t tell us anything about the difficulty of the chances each team is creating. Maybe a return of 1.11 is about right if all a team is doing is pinging it from the centre square.

Source: Why 2017 Results Are Flattering The Cats – Figuring Footy

Tower of Power after Round 3

What does it look like if you run 10,000 simulations and count how many times each team winds up in each position? This!

At this stage, there’s still lots of uncertainty, so teams are mostly long slashes, capable of finishing in many different positions. As the weeks go by, they tend to flatten out.

Adelaide are already settled in the top 4, though, the squiggle reckons, and Brisbane are very likely for the spoon.

Gold Coast and Freo evacuating those bottom rungs opened up a lot of space for other teams to fall into. That chute opening for Hawthorn all the way down to 17th is kind of terrifying.

Computers are beating the bookies

It’s been a rough start to the year for tipsters. And the start of a season is a tough time for computer models, which generally don’t know about personnel changes during the off-season.

Still, after three rounds, the computers models are doing okay!

Tips Bits
Figuring Footy 18 0.88
Squiggle 18 -0.96
PlusSixOne 17 1.28
Aggregate 17 0.48
Footy Maths Institute 17 -1.84
Punters 16 0.73
Matter of Stats 15 0.16
The Arc 15 0.04

“Bits” from Monash University rewards tipsters for saying a win was likely and punishes them for saying it was unlikely.

Squiggle has been fortunate with a few line-ball calls, doing well on raw tip numbers but badly burned on over-confident predictions that turned out to be upsets.

Figuring Footy has been strong on both. PlusSixOne has been excellent in probabilistic terms, and is currently leading in Bits.

Squiggle on Round 3

Animated!

So… Hawthorn. This isn’t an easy conversation. You’ve been there for me since I started posting squiggle stuff on BigFooty. You camped out among the premiership cups for months on end. You were a pleasure to watch and easy to predict.

It’s even easy to identify the moment it all went wrong for Hawthorn: Round 6, April 30, 2016, 4:35pm. That was when the Hawks, travelling at 4 wins and 1 loss after a series of narrow escapes, ran into GWS and started watching footballs flying over their heads. They lost by 75 points. It was the beginning of the end because if there was one thing the Hawks made clear during their period of dominance, it was that good teams don’t get thrashed.

Thrashings are very indicative. Squiggle pays a lot of attention to them, even more than wins. Very good teams don’t receive them, under any circumstances, not even when nothing’s going right. They cough up close losses but not thrashings. And they belt bad teams.

So after copping an 86-point belting from the Suns, the Hawks take the big plunge on the squiggle, while Gold Coast leap toward the middle of the pack:

Adelaide and GWS did what was expected, while Sydney had another bad week — again, not because their performance was so terrible, but because when you can only afford to lose 5 or 6 games for the year to make the top 4, it’s not great to accumulate three of them before your first win. They’re still rated the third-best team, but they probably need to go 16-3 from here, and that’s a huge ask.

A good week for the Cats, mainly because Sydney and the Bulldogs’ troubles freed up some breathing space in the top 4. Also good for Collingwood, who banked a win that few would have counted on, and stole ground from top-8 competitors in Hawthorn, Melbourne, and North.

Carlton and Essendon take a step to the right, mainly because of a heavily rain-affected game. But Fremantle overtake both after beating the Bulldogs.

The Tigers are now 3-0, but squiggle isn’t too excited yet. They’re a genuine finals chance, currently predicted to miss out on percentage only, but their results have been only mildly better than expectation. To really move, they need to belt Brisbane next week.

Flagpole! Pretty much business as usual here:

 

Squiggle: Round 2

Not as much dramatic squiggling this week, with most results falling somewhere around expectations. But a great one to be a Port Adelaide fan!

Port had the best week by solidifying their finals’ claims in an 89-point hammering of Fremantle. As a result, the top 7 is already LOCKED IN:

I may be going early on that. That isn’t really a sure thing. But right now there are seven teams who will probably be playing finals, plus a whole mess of teams who might.

The other top 6 teams – Adelaide, the Bulldogs, GWS, Sydney, and West Coast – also had pretty good weeks, or least not terrible ones. But that’s the problem: they all did. So no-one stole a break.

The Crows, for example, would be very happy with their win over the Hawks, but even though GWS’s 102-point demolition of Gold Coast proved that Adelaide’s Round 1 victory really meant something, so too did it confirm that the Giants are a serious obstacle to the flag. So it’s a good news/bad news situation.

The Swans and Cats are an interesting pair. You would probably rather be Sydney, who put up a good fight against the Bulldogs despite a raft of injuries. But the fact that Geelong are now 2-0 while Sydney are 0-2 is starting to bite. There isn’t usually much room for error at the top of the ladder, so although Sydney are rated the better team, the question becomes whether they’re so much better that they can overtake the Cats after giving them a 2-win head start.

North Melbourne had about as good a week as you can have when you lose by one point. And Gold Coast had about as good a week as you can have when you lose by 102, because Fremantle and Brisbane showed they’re bad enough to compete for the spoon, and Carlton doesn’t look like breaking out of the bottom 4, either.

Not much action on Flagpole this week, since it already loved Adelaide, and expected nothing less from them than what they delivered. But a handy bump for the Giants, Bulldogs, and Port.

For more: Live squiggle!Squiggle dials!

More on the importance of the early rounds

Two more articles on what early results really mean.

First a fantastic follow-up to the great piece last week from The Arc:

Here’s a version of that graph extended to the full home-and-away season. Cool, IMO. Using this chart, you can look up how many games your team is on pace to win for the year. For example – if your team has won 6 from their first 9 (a 6-3 record), then they’re on pace to win 13.9 for the year – enough to comfortably make the finals.

Source: More on the importance of the early rounds | The Arc

And here’s a particular examination of Round 1 upsets by Hurling People Now:

We have considered two classes of results: eventual finalists beaten in round one by teams who missed the finals, and eventual finalists beaten by other finalists who finished lower down the ladder.

Source: What does winning in round 1 mean?