MAFL 2010 : Round 4

If last weekend was the SSO in the Opera House this weekend is an acapella duo down the local pub.

We've just two bets and they're both priced at under $1.60. One wager is on the Pies, who face Hawthorn on Saturday, and the other is on the Saints, who take on Fremantle on Sunday.

Here are the details:

The paucity of wagering action is reflected in the simplicity of the weekend's Ready Reckoner the simple message of which is that we need both teams to win if we're to record a net profit.

You might have noticed from the MAFL Wagers table above that two of the line markets are yet to be posted on TAB Sportsbet; at this point they'd be redundant anyway since the head-to-head markets for these games are already offering $1.90 for both sides with no start at all. Three other games have line markets with starts of fewer than 12 points, which might help explain why you're finding it hard to settle on your tips this week.

Our own tipsters suffered no such self-doubt or uncertainty in arriving at their selections, which are shown in the table below (now that'd be a fun bit of AI development - a tipping algorithm that's uncertain about its tips, a bit overwhelmed by the data at its disposal and struggling to make a final selection, maybe outputting 'Cats by 6 ... No, wait a minute, I forgot about that game 12 seasons ago ... make that Port by 2 ... oh, but the Cats are at home, so let me just calculate something else ... carry the 3 ... okay make that Cats by 2 ... oh, but hang on, it's played on a Sunday in April isn't it ... actually, can you get back to me? ... give me another hour ... or maybe two ...').

This week I've included for the first time a column showing each tipster's season-long performance (though 24 games is shy of 30, the sample size sometimes suggested as the minimum necessary to purge a sample from the pejorative label of 'small'). Adding this column gave me the first opportunity to review the tipping performances of LAMP and HAMP, which I'm pleased to report are both superior to BKB's 62.5%.

Here's a summary of the tips:

• Essendon are 9-6 favourites over West Coast, though they're underdogs and not tipped by any of the margin-tipping tipsters. Chi tips the Eagles by just 2 points, making this his Game of the Round.
• Sydney are 14-1 favourites over the Roos, with Home Sweet Home the only tipster coming down on the side of the Roos. Despite the lopsidedness of the tipping the game appears likely to be a close one since the largest predicted margin is the bookie's and it is only 11.5 points.
• Carlton are 10-5 favourites over Adelaide, BKB being assigned Consult The Ladder's selection in the absence of a clear favourite in head-to-head prices. This game too looks destined to be a close one since the largest predicted margin is just 8 points. HAMP and LAMP are predicting margins of just 2 and 3 points respectively, making this one of their two Games of the Round.
• Collingwood are 14-1 favourites over Hawthorn. Easily Impressed I is the shaglike tipster for this game, tipping Hawthorn solely on the basis that it deems their 16-point loss impressive - or, I suppose more correctly, less unimpressive - than the Pies' 28-point loss. If this heuristic was any more one-dimensional it'd be a point (ooh look, maths humour).
• Brisbane are 8-7 favourites over the Bulldogs, with BKB again being allocated the selection of Consult The Ladder. This is yet another game thought likely to be won narrowly, Chi's tip of an 8 point victory by the Dogs being the largest predicted margin. The narrowness of victory predicted by HAMP and LAMP make this their other Game of the Round selection.
• Melbourne are 13-2 favourites over Richmond. Whilst ELO now rates Melbourne a better team than Richmond, the numerical magnitude of the Dees' superiority is narrowly insufficient to overcome Richmond's home ground advantage. Thus ELO is one of the two Tiger tippers, but ELO predicts just a 1 point margin making this ELO's Game of the Round. The only other Richmond selection comes from Home Sweet Home, a tipster also swayed by Richmond's home team status.
• Geelong are 10-5 favourites over Port Adelaide. Amongst the margin-tipsters, Chi's support is the most lukewarm as he's predicted a Cats win by just 8 points.
• St Kilda are the round's only unanimous choice. They face Fremantle. Chi is, again, the margin-tipster with the lowest predicted margin of victory for the Saints, but even he has them as 10-point favourites.

We finish with the week's line tips from HELP, which this week are far more conservative than they were last week, all of them having attached probabilities in the 59% to 67% range. Probabilities in that range provide little opportunity to rack up large probability scores on any of the measures, but they also preclude the possibility of anything catastrophic.

HELP's selections are, however, all away teams, so they're interesting tips if not particularly brave ones.

A reminder that this is the last round in which there'll be only one Fund active. Next week Hope starts trading and from Round 6 everything's live.

MAFL 2010 : Round 3 Results

Well that was quite a Sunday.

Investors awoke on Sunday morning with the weekend's profitability hinging on an improbable victory by the Dees against the Crows, which then had to be followed by an almost equally unlikely win by the Dockers against the Cats. In the end, Investors got both results, with a victory by the Dogs providing the proverbial marzipan on the sweet, baked, traditionally tea-accompanying confection.

Sunday's three wins more than offset the financial damage inflicted by Friday's and Saturday's two wins and two losses performance, leaving the Heuristic Fund up 11.75% on the weekend and up 7% on the season. That, in turn, left Investors with the Recommended Portfolio up 1.175% on the weekend and up 0.7% for the season, which means that Shadow has done enough to earn at least three more weeks in control of the Heuristic Fund.

Here are the details of the weekend's wagering:

Only four favourites won during the round, which had the unprecedented effect of driving BKB to third-bottom in our tipping race and delivering Follow The Streak and Easily Impressed I into outright leadership on 18 from 24. The strong tipping performance of these two heuristics has been mirrored in the profitability of their home-team only wagering performances, so much so that had Freo not claimed its dramatic victory over the Cats on Sunday evening, Follow The Streak would have had control of the Heuristic Fund for the next three weeks. (Since Follow The Streak and Easily Impressed I would have been equal on profitability the tie-breaking rule would have been invoked. This rule hands control to the tipster with the superior performance across season 2009. That rule puts Follow The Streak ahead of Easily Impressed I.)

So far this season we've not looked at MARS Ratings; it's about time we did.

St Kilda are rated a clear first at this stage of the season having increased their lead over the Cats with their 28-point victory over Collingwood this weekend. Sydney recorded the weekend's largest ladder climb, jumping three spots into sixth, overtaking the Blues, Hawks and Crows in doing so. Essendon registered the week's next-biggest jump, rising two places to eleventh.

Four teams' rankings dropped on the strength of their weekend performances: Adelaide dropped furthest, falling two places to ninth, while Carlton, Port and the Eagles each fell by just one spot.

Overall, that leaves nine teams rated 1,000 plus and Fremantle narrowly rated sub-1,000. Richmond appear to be making an early-season race for the bottom.

All margin predictors recorded solid performances over this round, reducing both their mean average prediction errors and their median average prediction errors so that now all but Chi have sub-30 mean APEs and all have median APEs of 27 or lower.

HAMP and LAMP remain stubbornly misordered in this table, with HAMP narrowly heading LAMP on mean APE, and LAMP heading HAMP on median APE. Chi is in the odd position of having the worst mean APE but the (equal) best median APE, while BKB's performance continues to demonstrate why bookmakers book holidays more often than they do losses.

In contrast to BKB, HELP turned in another uninspiring set of numbers this weekend, correctly tipping just four of eight line winners - a performance that's no better than chance - and registering probability scores less than those that a naive tipster would have produced.

Collingwood's appalling 4.17 on Friday night got me to wondering about recent kicking performances that had been as bad as or worse. Looking at the 20 seasons before this one I could find only one performance as bad as the Pies' and just four that were worse.

Actually, the overall kicking performance this weekend, which saw 190 goals and 228 behinds kicked - a percentage of just 45.5 - seemed remarkably poor. Indeed, a review of the aggregate kicking performances of all teams in home-and-away rounds since 1995 shows that this weekend was the second-worst in that period, surpassed only by the 45.2% performance recorded in Round 14 of 1997.

Just for the heck of it I then had a look at the worst kicking performances, combined for both teams in a single game, all-time and in the last 30 completed seasons.

That Geelong v Melbourne game must have tested the patience of even the hardiest supporter - twenty scoring shots and only one of them good enough to thread the big sticks. The lone six-pointer came in the second quarter, leaving spectators to find whatever joy they could in seeing Geelong kick six behinds to Melbourne's three in the second half. I do hope they took a good book with them.

MAFL 2010 : Round 3

This week the Heuristic Fund will again be guided by the selections of the heuristic tipster named Shadow, a situation that will not persist into next week if Shadow's Round 3 tips are responsible for the Fund's third straight weekly loss.

Were Shadow hell-bent on retaining control of the Heuristic Fund - assuming, for the sake of the narrative, that it were sentient at all - it might have chosen to respond to this situation by wagering on a couple of short-priced favourites, hoping to eke out a small profit and in so doing earn the right to manage the Heuristic Fund for at least another 3 weeks.

As it happens, there's only one markedly short-priced favourite this weekend - Sydney at $1.10 facing Richmond - and Shadow has, indeed, thrown bread at the Swans ... but also at six other teams.

Yes, that's right, Investors have bets in every game but one this weekend, the Roos being the only home team felt unworthy of a flutter by Shadow. Here are the details:

Three weeks ago few could have imagined the Dees priced at just $2.80 taking on one of last year's semi-finalists, but that's the situation we have this week and it's one that's prompted Shadow to lob 5% on the Dees. This is the highest-priced team that Shadow is supporting this week and is one of only two wagers that Shadow has made on underdogs, the other being another 5% on Fremantle at $2.50.

Not surprisingly, this makes the Melbourne v Adelaide and Fremantle v Geelong contests those with the greatest differences between potential profit and potential loss. Here are the Ready Reckoner details for the week:

With so many wagers it's not easy to summarise in words the minimum set of favourable outcomes that will ensure Investors earn a profit this week, so I've opted for a graphic instead.

In the graphic, the ticks in each row are against those games where the outcome must be favourable if we're to make a profit and the blanks represent games where, in the context of the ticks in the same row, we're indifferent to the result. Considered as a whole, each row represents one set of outcomes that will produce a profit, however small, for the Heuristic Fund.

So, for example, since there's a tick in every row against at least one of Friday's or Saturday's games we know that it won't be possible to make a profit on the entire weekend if we're 0 for 4 come Saturday night. If, instead, we clean sweep (swept?) the Friday and Saturday bets, the fact that every row has at least one tick against a Sunday game tells us that we'd still need at least one of the Sunday bets to win for us to finish ahead.

The last row of the graphic tells us that if Port's our only success across Friday and Saturday, we'll need the two underdog bets on Sunday to get home if we're to finish in the black. The eleventh row - the last row in which there's a tick against the St Kilda game - tells us that if the Saints win on Friday but the three Saturday wagers lose, we'll need all three Sunday bets to win if we're to register a profit.

You can generate and analyse a range of other what-if scenarios using this graphic. I feel like there should be a simpler way to describe the sets of favourable outcomes necessary for profitability, but this is a task I've wrestled with for a few years now and still haven't found a way to satisfactorily resolve. Your suggestions are welcomed.

Anyway, time for a look at our tipsters.

In Friday's game there's unanimous support for the Saints to topple the Pies. Amongst the margin-tippers only ELO has the Saints covering the spread and even then only by half a point.

Next, the underdog Eagles have majority support in their clash with the Roos, though four of the five margin-tippers, including the bookies, are selecting a Roos win. HAMP is the lone Eagle-supporter and has them winning by just 2 points, making this one of its two Games of the Round. LAMP's on the Roos (which sounds a bit like the name for a depressing documentary on the Discovery Channel chronicling the night-time culling of one half of our coat of arms) but is predicting just a 4 point win, which also makes this one of its two Games of the Round. Assuming that the line market is eventually posted as Roos -6.5 it'll also be a Game of the Round for the bookies. The sentiment seems to be then that this game will be a close one.

In the Swans v Tigers game, Sydney are the unanimous selection, with comfortable wins predicted by all of the margin-tippers except Chi who's predicting a margin of only a point, making this his Game of the Round. Carlton, facing the Dons at the G on Saturday evening, are another unanimous tip, by margins ranging from one to four goals.

The Port v Lions game is the other game this weekend that seems likely to be a thriller according to our margin-tippers. ELO, HAMP and LAMP - and probably the bookies, again assuming the line market is posted with 6.5 points start to one team or the other - have this game as a Game of the Round, each predicting margins of 4 points or fewer. Majority tipping support is with the home team as it is in all but one game this week.

Melbourne take on Adelaide at the G on Sunday and enjoy unanimous support from all the non margin-tippers. Adelaide, on the other hand, has unanimous support from all margin-tippers and is predicted by them to win by between 1.5 and 3 goals.

In the Sunday game at Docklands where the Dogs face the Hawks, Chi and Consult the Ladder are the only tipsters opting for an underdog Hawks victory, and in the weekend's final game, which sees Fremantle pitted against the Cats, we again find unanimous non margin-tipper support for one team (Fremantle) and unanimous margin-tipper support for the other (Geelong).

So, in summary, this week's majority tips are: St Kilda (15-0), West Coast (10-5), Sydney (15-0), Carlton (15-0), Port Adelaide (10-5), Melbourne (10-5), Western Bulldogs (13-2) and Fremantle (10-5).

Lastly, let's have a look at HELP's line betting tips for the week.

There are a few high-risk probability forecasts in that lot, most obviously the 97% probability attaching to Richmond's winning on line betting, an outcome that will require the Tigers to lose by 39 points or fewer.

MAFL 2010 : Round 2 Results

If you didn't tip the round this weekend you've only yourself to blame. All eight winners were published in the online (and probably the print) version of Melbourne's Herald Sun late on Wednesday night as one of their forecaster's considered selections.

They were Jennifer Hawkins' tips.

It was that kind of round.

Investors are entitled to think themselves lucky that Collingwood snuck home against the Dees but equally aggrieved at the barnstorming finish from the Cats that prevented a Hawks payoff at $2.50, which would have been sufficient to drag the Heuristic Fund into profitability. In all, the weekend's two losses and one win meant that Investors with the Recommended Portfolio dropped 0.42% of Total Funds, leaving them down 0.48% on the season.

If Shadow records another loss in Round 3 it will surrender control of the Heuristic-Based Fund to some other algorithm (assuming that some other algorithm has a superior return at that point, which is not the case at present).

Here are the details of this round's wagers and results:

With only five favourites grabbing the points and six teams winning that were in a superior ladder position to their opponent, it was a good round for the simpler heuristic tipsters. These tipsters tended to follow Consult the Ladder this week and so bagged six from eight:

ELO went with the favourites in all eight games and so scored only five. Chi's only underdog tip was the Dees and, although vindicated, he wasn't rewarded for his bravery. As a result he scored only four for the week.

That leaves our tipping competition with nine equal leaders, all on 12 from 16, with ELO and BKB one tip back on 11 and then Chi back another two tips on nine. Home Sweet Home trails the pack on just 7 from 16.

The blowout wins of St Kilda and the Dogs, the surprise victories of Sydney and Port, and the narrower-than-expected loss of the Dees all combined to inflate the absolute prediction errors of the margin-tipsters this weekend.

HAMP did best, recording 34.0 points per game for the round, better even than BKB, which recorded 34.4. Next best were LAMP (37.5) and ELO (37.9), with Chi (39.6) responsible for the round's worst MAPE.

Cumulatively, that leaves the situation as shown here:

On mean APE then, BKB leads narrowly from HAMP, whereas on median APE, BKB is tied with Chi. At this point, HAMP leads LAMP on mean APE, while for median APE the situation is reversed. This is, as you might recognise, the opposite of what we'd ultimately expect since LAMP is meant to be low average and HAMP is meant to be low median. Still, it's only early days.

Let's finish again this week by reviewing the performance of HELP.

In short, it wasn't a weekend for the HELP family scrapbook. Just three correct line tips and considerably worse-than-naive probability scores on all three measures.

MAFL 2010 : Round 2

Before I launch into this week's wagering and tipping information, a final reminder: if you want to take part in this year's blog-readers' competition you need to have an entry to me before centre-bounce Thursday night. Details of the competition are in this blog entry.

Entry is free and there are no prizes, which I think has an appealling symmetry to it. Entries can be e-mailed to me at the usual address.

Anyway, onto the footy, which again starts on a Thursday this week but which has no Friday game, it now being traditional for the AFL to avoid games on Good Friday.

The Heuristic Fund is the only Fund active this week and is still under the stewardship of Shadow despite a small loss last weekend. Shadow's opted for just three bets this weekend, two of them on teams giving six or more goals start, making these bets akin to a small investment in the sovereign debt of a generally stable but occasionally startling regime. Even if both of these bets are landed the Heuristic Fund will rise by less than 0.1%, which for many Investors won't even be enough to round them up to the next highest 5 cents.

Our excitement then is all down to the weekend's third and final wager, which is on the underdog Hawks taking on the Cats on Monday and currently paying $2.50 the win.

Here are the weekend wagering details:

For completeness, I'll also provide the Ready Reckoner, dull though it is:

My first thought when I saw the opening markets this week was that it'd been a long time since we'd had two $8.50 shots or longer in the same round, but when I checked I discovered that we'd had Freo at $10 playing Geelong and Melbourne at $11 playing St Kilda in the final home-and-away round of last season. Oh how quickly the memory fades.

This weekend the teams offering the snowball-in-a-warm-place-like odds are Richmond and Melbourne, but the bookies' scorn hasn't been enough to discourage Chi from waving a paw in the direction of the Dees. Perhaps he's making an early and desperate bid to snatch control of the Heuristic Fund should Shadow turn in another two consecutive rounds of losses.

Chi's not alone amongst the heuristic tipsters in plumping for underdog victories this weekend, though he and Home Sweet Home are undoubtedly at the more distant extremities of that particular limb.

Here's a quick summary of the tipping highlights for each game:

• Carlton (away to Brisbane), by virtue of its thumping win over Richmond in Round 1 and the proclivity of most non margin-tipping heuristics to revert to ladder position when they are otherwise undecided, is the first of the underdog teams with majority tipster support, favoured by nine tipsters but not by any with a memory longer than last week.
• Collingwood (at home to Melbourne) is favoured by all but one tipster though clearly not by every man and his dog as I have the dissenting dog sitting next to me as I type this. Chi at least has the commonsense to make this his Game of the Round; he's tipping Melbourne by just 2 points.
• St Kilda (at home to the Roos) is the weekend's only unanimous choice of our tipsters. Amongst the margin-tippers only LAMP has them winning by enough to cover the 37.5 point spread the bookies are insisting they give.
• Port Adelaide (away to West Coast) is another of the tipster-favoured underdogs and is supported by the same amnesia addled set of tipsters that have opted for Carlton. HAMP, one of the tipsters siding with the bookies, has West Coast winning by 10 points, making this game one of its two Games of the Round. None of the other margin-tippers forecast this to be a blowout either - the largest forecast margin is Chi's 19 points.
• Sydney (away to Adelaide) is another underdog supported by the same group of tipsters as Port and Carlton. HAMP rates this game as its other Game of the Round and tips Adelaide by 10 points.
• Fremantle (away to Essendon) is the last of the quartet of teams with identical patterns of tipster support. The margin-tippers foresee this game too as being close; LAMP's predicted margin of 23 points is the largest among them.
• The Dogs (away to Richmond) have only Home Sweet Home standing between them and a clean sweep of supporters and there's not a lot they could have done bar lobbying to have the game deemed a Dogs home game to have convinced Home Sweet Home to have tipped otherwise.
• Hawthorn (at home to Geelong) is the fifth and final tipster-favoured underdog for the week. Once more, all the support is coming from the non margin-tipping tipsters. ELO (who tips Geelong by 5) and LAMP (who tips Geelong by 9) both have this as their Game of the Round, and the bookies are only offering Hawks' backers 13.5 points start.

Which leaves just one item for us to cover: the HELP forecasts.

This week HELP has adopted the Home Sweet Home approach to prediction in selecting all eight home teams as line betting winners, though in its case at least for six of the eight games it's enjoying the benefit of points start.

As you can see, HELP is quite confident about each of its selections, attaching probabilities ranging from 77% to 86% to each.

Good tipping, good punting and good fortune.