MAFL 2010 : Round 14

If you're an Investor this is probably a blog best read seated.

In six of the weekend's eight games the home team is the favourite, and in five of them it's the short-priced favourite. The reaction from the MAFL Funds to this circumstance - especially from the New Heritage Fund - has been akin to the response you get if you open a packet that sounds even vaguely like a chip packet within earshot of Chi: immediate and overwhelming interest, palpable desire and a fixation on securing a piece of whatever's on offer.

Here's what the result of all that interest looks like.

MAFL 2010 : Team Dashboard for Round 13

Sorry that this is a little late this week. I think I've been mentally recovering from the hiding that MAFL took last weekend.

Anyway, here's the MAFL Team Dashboard:

MAFL 2010 : Round 13 Results (Final)

This'll be brief.

When scanning the week's Ready Reckoner, never do I consider the "Best Possible" or "Worst Possible" results as lying within the feasible set of actual wagering outcomes. How wrong I've been.

Three games, three losses. Waiter, may I have the menu for Round 14 please?

MAFL 2010 : Round 13 - Part II

Even with two attractive-looking matchups in the Cats v Saints and Swans v Pies games, this weekend can't help but seem like the stale bit of the loaf that is Round 13. (Apologies if you're a Melbourne or Adelaide fan, but I'm finding it hard to get enthused about 13th v 15th.)

The weekend's status might be elevated though if the Cats, Swans and Dees all wins, the Cats doing so by 21 points or more, since then the Recommended Portfolio will rise by about 3.9% more than offsetting, if barely, the losses suffered last weekend.

MAFL 2010 : Round 13 Results (Interim)

If I've much more practice in being philosophical after wagering losses I fear I'll wind up smoking a pipe, blogging about the meaning of truth, affecting a permanent, faraway look and calling myself Bruce. (Any Monty Python fans here?).

So far, Round 13 has not been a happy one for any Investor. The Recommended Portfolio has shed 3.7%, MIN#002's Portfolio has dropped 7.5%, and MIN#017's Portfolio has fallen 7.1%, these falls largely due to poor showings by the Blues and the Lions, who went down by 9 and 19 points respectively.

Given the likely prices on offer for the remaining three games, it seems unlikely that a net profit for the round will be the final outcome. Only an upset Sydney win over the Pies might make a difference, but it doesn't look as if any of the Funds is especially keen to invest in that particular result.

MAFL 2010 : Round 13 - Part I

And so we enter the first half - well five-eighths actually - of the split Round 13.

Recommended Portfolio holders have wagers in four of the week's five games, with the Eagles v Dogs clash the only one failing to attract the interest of at least one Fund. New Heritage is the boldest Fund (who'd have guessed?), wagering about 22% of the Fund on three bets including two that are for around 10% of the Fund both of which are on teams that are favourites but by no means raging hot ones in the form of the Hawks and Lions. The third bet is a contrarian, away team wager on Port Adelaide that, when offset by the wagers of Prudence and the Heuristic-Based Funds on the Roos in the same game, makes the outcome at best a small profit for those with the Recommended Portfolio.

MAFL 2010 : Team Dashboard for Round 12

Here's the week's MAFL Team Dashboard.

This week I thought we'd take a look at the correlations between team ladder position and the performance statistics in the Scoring Shot Data and Quarter-By-Quarter Performance sections of the Dashboard.

Here's the summary:

Scoring Shots

• The (rank) correlation between Scoring Shots For (measure A) and Ladder Position is +0.75. It would be much higher but for the effect of St Kilda who are 12th on this measure but 2nd on the ladder.
• The (rank) correlation between Scoring Shots Against (measure B) and Ladder Position is +0.84.
• The (rank) correlation between the Scoring Shot Differential (measure C) and Ladder Position is +0.98.
• Creating and preventing scoring shots seem to be of roughly equal importance in generating success so far this season.

Scoring Shot Conversion

• The (rank) correlation between Own Conversion Rate (measure D) and Ladder Position is +0.72. Collingwood, who are 3rd on the ladder but an astonishing 14th on this measure, drag this correlation down. The Pies could surely have had no better reminder of the importance of converting opportunities than that provided by their 9.22 performance on the weekend, which cost them 2, and almost 4, competition points.
• The (rank) correlation between Opponents' Conversion Rate (measure E) and Ladder Position is +0.08.
• The (rank) correlation between Conversion Rate Differential (measure F) and Ladder Position is +0.41.
• Clearly, this season, success has been far more about converting opportunities than it has been about preventing opponents from doing the same.

Quarter-By-Quarter Performance

• The (rank) correlation between ranking on Q1 performance and Ladder Position is +0.79.
• The (rank) correlation between ranking on Q2 performance and Ladder Position is +0.58, dragged down by St Kilda, who are 2nd on the ladder but 14th on Q2 performances, having won just 4 from 12 second terms.
• The (rank) correlation between ranking on Q3 performance and Ladder Position is +0.69
• The (rank) correlation between ranking on Q4 performance and Ladder Position is +0.65. Two teams have depressed this correlation, Collingwood and Hawthorn, the former being 3rd on the ladder but 11th on Q4 performances, and the latter being 8th on the ladder but 16th on Q4 performances.
• Unusually, it's been Q1 performances that have been most indicative of a game's outcome this season. Winning teams have won first quarters in 71 of the 96 games played so far this season (and they've drawn 2 more), which is higher than any other quarter.
  To put this in some historical context, last season, winning teams won just 68.9% of games (ignoring draws). This season they've won 75.8% (ignoring the draw).

MAFL 2010 : Round 12 Results

As I've probably mentioned before, I dislike draws, not so much for their inconclusive nature, but more for the fact that they make the statistics messy. All the formulae in my spreadsheets that calculate returns need to cater for this once-or-twice-in-a-season phenomenon, and all the tipping statistics now sport an awkward .5 at the end.

MAFL 2010 : Round 12

Is it really the second half of the season already?

Recommended Portfolio holders can look forward to another weekend of cheering for favourites one game and underdogs the next. This week they've one game (Kangaroos v Carlton) in which their interest is solely in the line and not the head-to-head result, and another game in which they've no interest at all (Richmond v West Coast).

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?

MAFL 2010 : Team Dashboard for Round 11

Here's the week's MAFL Team Dashboard.

A few things to note in this data:

• Collingwood, despite being placed second on the ladder, have the second-worst opponent conversion rate (56.4%) and a relatively poor record in final terms (which was starkly in evidence on Sunday night)
• Hawthorn are in the eight at least partly because they've prevented their opponents from converting opportunities in front of goal. They're struggling in the second half of games, particularly in final terms where they have a 1-10 record.
• St Kilda, Essendon and Fremantle are all allowing their opponents to convert too many of their opportunities. Essendon's struggles in first and last terms, Fremantle in third terms, and St Kilda in second terms.
• Relative to their respective ladder positions, Melbourne and Richmond are ranked highly on opponent conversion rate.
• Melbourne performs significantly better is third terms.
• Port Adelaide has mastered the art of the whirlwind finish, winning almost two-thirds of the final terms it's played. This hasn't been enough in 6 games out of 11 however.
• The Lions continue to pair lousy first halves with stunning second halves. The round just finished provided an excellent example of this, as the Lions were outscored 10 goals to 5 by the Roos in the first half of their game, before kicking 8 goals to 2 in the second half.
• West Coast performs relatively poorly in second halves.
• The Bulldogs are the best in the league for second terms.

MAFL 2010 : Round 11 Results

Absent an upset victory by either the Tigers or the Eagles - both of which outcomes seemed possible for at least a portion of their respective games - that was just about as good a weekend as Investors with the Recommended Portfolio might have hoped for.

An improbable Dogs victory also tantalised for a few minutes late in the final term on Friday, but that outcome ultimately proved unattainable, leaving the Recommended Portfolio up 2.4c on the weekend and down now just 11.1c on the season.

The portfolio of MIN#017 also finished in the black, though the 8.4c hike has left much still to do to return that Portfolio to parity, languishing as it does still some 37c down on the season. Still, how does one eat an elephant? The conventional answer is: one spoonful at a time.

MIN#002 was the only Investor to suffer losses this week. His portfolio fell 6.3c to 75.2c, a victim of Hope's curiously lacklustre performance so far this season, which has seen it land just 4 of 12 wagers.

In-Running Prediction of the Winner of an AFL Game

I've been planning to create this model for a while.

With it, you can calculate the probability that the home team will eventually prevail given the state of the match at a particular point in the game.

MAFL 2010 : Round 11

Every week I learn a little more about my tolerance for risk.

I feel far more comfortable with an array of wagers that includes the Tigers at $5.50 and West Coast at $6.00 than I did with last week's festival of favourites. Wagering at odds-on prices still feels inordinately Sysyphean to me.

Looking At Team Performance Quarter-By-Quarter

AFL Football - as the cliche goes - is a game of four quarters. The benefit of this arrangement is that AFL scores provide twice as much information about the ebb and flow of each contest as the scores of any other form of football in this country.

With the quarter-by-quarter information alone we can perform some interesting analyses for every team.