MAFL 2010 : Round 10 Results

When seven of the weekend's eight contests produce the result that you expected - the right team winning head-to-head, the right team winning on handicap, in some games both - I think you've a reasonable expectation of profit.

No such luck.

Port Adelaide just had too much money riding on them, so the triumphs in the other seven contests nevertheless left those with the Recommended Portfolio down a little over 1 cent for the round. MIN#002 fared no better, his portfolio also dropping by about a cent, while the portfolio of MIN#017 did even worse, dropping over 5 cents.

Here's the MAFL Dashboard for the round.

Most tipsters managed 5 from 8 this week though Home Sweet Home recorded a 7 and Short-Term memory I scored only 3, dropping it to third on the ladder, two tips behind Easily Impressed I and one tip behind Easily Impressed II. Only five favourites won, so BKB made no impression on most of the tipsters above it and remains 6 tips from joint-leadership.

It's interesting to note that no tipster has a better tipping record over the past 5 rounds than it has over the season as a whole, a reflection of how difficult tipping has been recently.

On MARS Ratings, Geelong widened the gap between itself and the Pies and the Dogs. It now has a 16.5 Ratings point lead over the second placed Pies and a lead of almost 19 Ratings points over the third placed Dogs.

Three teams climbed a spot on the Ratings ladder (Fremantle, Essendon and the Eagles), and three fell one spot (Carlton, Adelaide and Port Adelaide). Eleven teams are now rated 990+, and with a rating of 1,000 generally sufficient to see a team make the finals, we can look forward to a tightly contested second half of the season.

BKB still leads the Margin Tipsters on the Mean APE metric, but has been joined by ELO in the race for Median APE honours. LAMP has narrowed the gap between it and BKB on the Mean APE measure, knocking more than 0.6 points from its average this week while BKB knocked only 0.5 points from its average; LAMP is now just over 1 point per game behind BKB.

HELP did nothing much this weekend, correctly tipping just 3 of 8 line results and generally performing much as you'd expect a naive tipster to perform.

MAFL 2010 : Round 10

At some point earlier today, for reasons I expect we'll never know, TAB Sportsbet felt comfortable in reopening the Saints v Crows markets, pricing them exactly where they'd been a couple of days previously when the allegations broke and attracting wagers from four of the five head-to-head wagering MAFL Funds. Among them only Hope abstained, as in fact it has on all eight games this round.

The ELO-Based Fund also chose not to bet on this game, deeming the 27.5 points start that the Saints were required to give just 1 point too many.

All told, the MAFL Funds have made 26 wagers this week, representing around 30% of the initial Funds placed in the Recommended Portfolio. All the head-to-head wagers are on favourites, at prices from $1.03 (yes - Geelong again) to $1.30.

The only wagers we have on underdogs are line bets - one on Essendon +19.5 versus the Dogs, and the other on the Lions +21.5 versus Collingwood.

Here's the detail:

This week Geelong carry the largest proportion of Recommended Portfolio funds though their ridiculously low price makes the upside from the head-to-head portion of those wagers fairly insignificant. As a consequence, it's the Port v Tigers and not the Cats v Dees game that represents the greatest difference between the best and worst possible outcomes.

Five matches have swings of around 5.8% or more riding on their outcome. None of them have upside greater than 1.4%. Such is the price of backing favourites. It's going to be a tough week to make a profit if you're in the Recommended Portfolio.

Here's the week's Ready Reckoner:

On the tipping front it's wholesale harmony this week. On three of the matches there's unanimity and in two more there's only a single dissenting tipster.

• The Dogs are 14-1 favourites over Essendon. Only Home Sweet Home is duty-bound to opt for the Dons. Notwithstanding the overwhelming support for the Dogs, both BKB and LAMP have this as their Game of the Round (though neither is tipping a single digit victory margin)
• Geelong are unanimous favourites over the Dees. Predicted margins range from 26 points to 50.5 points, so this could be a game that gets boring pretty quickly.
• Port Adelaide are unanimous favourites over the Tigers. For this game too the margin predictions are quite high - none is below 17 points.
• Collingwood are 13-2 favourites over the Lions. Tipped margins for the Lions start at 13 points and work their way up to 34 points.
• St Kilda are 14-1 favourites over the Crows, with all but one of the margin tippers predicting Saints victories by between 27 and 32 points.
• Hawthorn are 13-2 favourites over Sydney. This is the Game of the Round for ELO (tipping a Hawks victory by 4 points) and HAMP (tipping a Hawks victory by 23 points, which makes something of a mockery of the notion of a Game of the Round).
• Carlton are 12-3 favourites over the Eagles. Chi is one of the three dissenting votes. He has the Eagles winning by a point, making this his Game of the Round.
• Fremantle are unanimous favourites over the Roos. Predicted victory margins are from 14 points to 40 points.

The average number of dissenting tipsters per game is only 1.13 this week, a long way from last week's 3.25. So, the surprisals forecast for this week would be very low.

HELP's continues on its eccentric way, this week tipping all eight away teams, six of them receiving start, with probability estimates from 62% to 81%.

Here's to an exceptionally good weekend for BKB tipping ...

MAFL 2010 : Round 10 (Coming Soon to a Browser Near You)

Well normally I'd be posting this week's pre-round blog, but, as I type this, the Saints' alleged player sex scandal is still unresolved, at least to the satisfaction of the TAB Sportsbet bookie. As a consequence all St Kilda v Adelaide markets are suspended.

So, we've no ability to back the Saints, which we probably will both on the head-to-head and line markets once we're able. I'll wait 24 hours and see what happens.

MAFL 2010 : Round 9 Results

For the third week in succession, those with the Recommended Portfolio were let down by the Saints' performance in the last game of the round. In Rounds 7 and 8 it was the Saints' ineptitude that caused the disappointment; in Round 9 that ineptitude was nowhere to be seen when Investors most needed it.

Not that the weekend's losses can be entirely attributed to the Saints' victory on Sunday evening. Collingwood, the Roos, Sydney and Carlton all did their bits too, offset only - and not completely - by Essendon, Melbourne and Adelaide victories.

This week I'm trialling a new way of presenting the various pieces of information about wagers, tips, team ratings and margin prediction. I call it the MAFL Dashboard.

In the first part of the MAFL Wagering section you can see that only one of the six Funds is currently priced above its buy-in price of $1, and you see that three Funds made money this round (Prudence, Shadow and Heuristic-Based) and the other three Funds lost money. You can also see each Fund's season long performance statistics and price history.

Below this you'll find the same information for the various portfolios. You'll see that the Recommended Portfolio dropped 1.3c this week, the MIN#002 Portfolio rose by 1.9c, and the MIN#017 Portfolio dropped 2.6c. This leaves all portfolios in varying states of unprofitability.

Next is the MAFL Tipping section, which holds all the regular information about the performance of the 13 MAFL tipsters. Short-Term Memory I and Easily Impressed I currently head our tipping competition on 52 from 72 (72%). BKB continues to struggle, scoring just four this week (the Tipping Performance - Last 5 Rounds section has this information), leaving it now six tips behind the leaders.

The column headed Return (Home) records the profit or loss that would have accrued to someone level-stake betting on the tips of the relevant tipster whenever that tipster predicted a home team victory. So far this season, following that strategy with the predictions emanating from Short-Term Memory I would have been the most lucrative, yielding a profit of 9.63 units. Adopting the same strategy with Shadow, as the Recommended Portfolio has been via Shadow's own Fund and via its control of the Heuristic Fund, has yielded a profit of 6.18 units. Incidentally, Shadow made money this weekend and so will retain control of the Heuristic Fund for at least another three rounds.

In the right-hand portion of this section there is information about the recent tipping form of each tipster, as evidenced by its accuracy in each of the last five rounds. The two tipsters currently leading the overall tipping competition also have the (equal) best performances of all tipsters across rounds 4 to 9. In these five rounds they've tipped 28 winners.

Underneath the MAFL Tipping section is the MARS Ratings section. This week, seven teams moved up or down the MARS Ratings ladder. Largest amongst these moves was the two-rung climb recorded by the Hawks based on their 60-point victory over the Blues, which earned them 5.6 ratings points. Currently, the seven highest-ranted teams are also the top seven from the competition ladder, albeit in a different order. The eighth-highest rated team is Brisbane, who sit eleventh on the competition table. Port are eighth on the ladder, but are rated twelfth.

In the chart on the right of this section you track the ratings trajectories of each team.

The final section is the Margin Predictors section and it records the performance of the five MAFL Margin Predictors. BKB still has the season's best margin predictions, whether you rank based on Mean Absolute Prediction Error or on Median Absolute Prediction Error. LAMP is now second on Mean APE while ELO is second on Median APE. The chart on the right shows each Margin Predictor's Mean APE as at the end of every round of the season.

I've not included HELP's data in the dashboard since its unspectacular performance seems unworthy of considered attention.

This week HELP correctly predicted 5 of the 8 line results and moved to a 50% win-loss record for the season. Its very high levels of confidence in all of its predictions meant that its probability scores ended up sub-naive for the second successive week.

In the next day or so I'll be posting another blog in which I'll introduce one more dashboard, this one providing information about team performances.

MAFL 2010 : Round 9

Just when you get into a routine, someone has to go and change something.

This week the TAB Sportsbet bookie decided to post the line markets a day early, leaving me with the dilemma of deciding whether to follow the time-honoured strategy of placing bets around noon on Wednesday or, instead, to follow the other time-honoured strategy of placing bets just after the line markets go up. In the past, save for those weeks where there's been a Thursday game, these two events have coincided.

Worse was the fact that only half the line markets were posted, so I couldn't make all the bets I wanted to anyway.

Well the bets have been placed though we're still waiting for four more line markets to be posted, three of which we'll be wagering on. (I've included these wagers in the MAFL Wagers summary and in the Ready Reckoner, though the latter might need to change if we don't secure a price of $1.90 for the three line market bets we want to make.)

(Update: It's now Thursday evening and we've placed the three remaining line bets. On two of the bets we've secured more favourable terms than I expected: backing Adelaide we wound up getting 7.5 points start rather than 6.5, and backing Sydney we received a price of $1.95 rather than $1.90. In the other bet we took West Coast +6.5 points but only received a price of $1.80. The Ready Reckoner below now reflects these wagers.)

Investors holding the Recommended Portfolio have 23 wagers this weekend - including the three wagers-in-waiting - just one fewer than they had last weekend. New Heritage has six of those wagers, Prudence and Hope have two each, Shadow and the Heuristic-Based Funds have three each, and ELO-Based will have the remaining seven.

In total, Investors with the Recommended Portfolio will have about 19% of their funds at risk this week, again only a tad less than they risked - and significantly lost - last weekend.

In aggregate, Essendon carries the majority of the week's wagers. They're priced at $1.28 and are playing Richmond, a team that appear to have decided to act as this year's quasi-bye, thereby allowing other teams to become accustomed to what they'll face next year when the Gold Coast joins the competition. Hawks fans might have a somewhat different view, of course, as their team went perilously close last weekend to dropping points to the bye.

Other bets are at prices ranging from $1.36 to $2.25, so none of the funds at risk can reasonably be tagged "best forgotten".

Here's the detail:

For those with the Recommended Portfolio, the Essendon v Richmond clash, by virtue of the shedload of cash on the Dons, represents the largest swing between best and worst outcomes. It also represents by some considerable margin the largest downside risk.

The Adelaide v Lions game carries the second largest swing between best and worst outcomes, which it does because it promises the largest upside should the Crows win and cover the spread but because it also threatens the second largest downside should the Crows lose.

Here's the Ready Reckoner in full (subject to amendment [Update: now duly amended] once the three remaining line bets are placed):

For the tipsters it's a weekend of moderate agreement, with unanimity in just one of the games.

• The Pies are 11-4 favourites over Geelong. The Cats can count BKB, Chi and the Easily Impressed brothers amongst their supporters, though BKB looks likely to have this game as one of its four - yes, four - Games of the Round, and no margin-tipper is predicting a victory margin in excess of 8 points.
• The Dogs are 14-1 favourites over the Roos, with only Home Sweet Home tipping the upset. All five margin-tippers are on the Dogs with margins ranging from 13 to 24.5 points.
• Fremantle are 9-6 favourites over the Swans, though all the margin-tippers are predicting a Swans victory. BKB will have this as another Game of the Round.
• Essendon are the week's only unanimous favourite. They face Richmond and are tipped to win by margins from 16 to 34 points.
• Port Adelaide are 12-3 favourites over the Dees. Three of the five margin-tippers - LAMP and BKB being the exceptions - are tipping Port victories, including ELO, who is tipping Melbourne by just 1 point, making this its Game of the Round.
• Adelaide are 10-5 favourites over the Lions. This is the Game of the Round for Chi (tipping a Crows victory by 2 points), LAMP (tipping a Lions victory by 1 point) and BKB (tipping a Lions victory by 6.5 points)
• Carlton are 11-4 favourites over the Hawks and are tipped by all five margin-tippers with margins ranging from 10 to 27 points.
• St Kilda are 9-6 favourites over the Eagles. This is the final Game of the Round for BKB. None of the margin-tippers are suggesting that either team will win by a sizeable margin - the largest tipped victory margin for St Kilda is 13 points and for the Eagles is 6 points.

The average number of dissenting tipsters per game is, therefore, about 3.5. This fact, coupled with the bookie's generally miserly points start offerings, suggests that this will be a difficult round to tip. Only the Dons and the Dogs might reasonably be considered 'bankers' and four, maybe five of the remaining six contests have a coin-tossy feel to them.

Whilst seasoned judges might be expressing high degrees of uncertainty about the head-to-head results, HELP's expressing near-certainty about the result of all eight games when adjusted for points start.

Remarkably, all eight HELP predictions are for the away teams. In contrast, the ELO-Based Fund will be making seven wagers on home teams. I think we all know which tipster we want to be incorrect more often.

This week I'll finish by providing my short version of the competition ladder, from which I'd like to highlight the Saints' performance. Despite losing three of their last four games they remain in the top eight. The table shows that this is not because of their points-scoring ability (for which they're ranked equal fourth last) but is instead attributable to their defensive skills: they've allowed only 583 points in their eight games, including only 10.5 goals per game.