AFL 2009 Season - Finals Week 4 Predictions - Grand Final

Apologies again foir the late posting of these, though given the predictions it's probably best they had as little expsure as possible.  As has been the case in most of the finals the player selections has been decisive in the final probabilities.  Geelong were tipped slightly based on team form alone, but some nuances in the players selected has swung things in quite a bit in St Kilda's favour.

I find it interesting that Geelong are favoured as much as they are, they have dropped a few games recently against less favoured opposition, whereas St Kilda only lost a couple of games by less than a goal.  Perhaps they shouldn't be as highly rated as they are below, but it's a method that was worked great all season so what can you do?

Team 1	Team 2	Venue	Pr 1	Pr 2
St Kilda	Geelong	MCG	85%	14%

Total tips for the season: 128 from 184 (70%)
Total tips for finals: 5 from 8 (63%)

EPL 2009/10 Season - Week 6 Predictions

As with the A-League tipping it seems consistency is the key, tipping 7 correct results for the 3rd week in a row now.  And again like the A-League we are now in the top 7% of all EPL tippers on footytips.  We are now sitting on 62.5% correct results for the year, about 5% ahead of where we'd expect to be at years end so the early season results are very promising.

It was also a great week for betting as our 4 bets for the week - Burnley, Everton, Chelsea and Manchester United - the latter result not being confirmed until the 5th minute of injury time after United had taken the lead 3 times during the match, only for City to equalise every time.

Here are this week's predicitions, no huge surprises in terms of tipping or bets.  

Date	Home Team	Away Team	Pr Home	Pr Draw	Pr Away
26/09/2009	Portsmouth	Everton	25%	29%	46%
26/09/2009	Birmingham City	Bolton Wanderers	43%	30%	27%
26/09/2009	Blackburn Rovers	Aston Villa	30%	30%	40%
26/09/2009	Fulham	Arsenal	18%	25%	57%
26/09/2009	Liverpool	Hull City	90%	7%	3%
26/09/2009	Stoke City	Manchester United	9%	17%	73%
26/09/2009	Tottenham Hotspur	Burnley	64%	22%	14%
26/09/2009	Wigan Athletic	Chelsea	9%	17%	75%
27/09/2009	Sunderland	Wolverhampton Wanderers	45%	29%	26%
28/09/2009	Manchester City	West Ham United	54%	27%	20%

Total tips for the season: 35 from 56 (63%)
Return on Investment for the season: +24%

A-League 2009/10 Season - Round 8 Predictions

We tipped 2 out of 5 results again for the 5th week in a row for the relatively low accuracy of 43% this season.  However, this is enough to put us in the top 7% of all A-League tippers at footytips, suggesting that perhaps so far this has been a tough season to tip - or perhaps the A-League in general is hard to tip.  A strong case for the unpredicatble nature of the A-League can be found by looking at the current form of all the teams - only one team has won more than two of it's past five games, that being Perth Glory who finished 2nd bottom last season.

The predictions for these week show we're tipping all home teams for the 2nd week in a row.  Indeed, looking at the odds for this week, the home teams are all paying between $2.35 to $2.40, so we are pretty much in line with the bookies.

Date	Team 1	Team 2	Venue	Pr T1	Pr Draw	Pr T2
25/09/2009	Newcastle Jets	Perth Glory	EnergyAustralia Stadium	43%	26%	31%
26/09/2009	Gold Coast	Melbourne Victory	Skilled Park	39%	27%	34%
27/09/2009	New Zealand	Central Coast Mariners	Westpac Stadium	38%	27%	35%
27/09/2009	Queensland Roar	Sydney FC	Suncorp Stadium	45%	26%	29%
27/09/2009	North Queensland	Adelaide United	Dairy Farmers Stadium	40%	27%	33%

Total tips for the season: 15 from 35 (43%)

AFL 2009 Season - Brownlow Medal Results

An extremely successful year was had this year betting on the Brownlow medal courtesy of the predictions released on this site - thanks of course to Gary Ablett winning at odds of $3 (at least when I placed my bet), massive value when I rated him a 75% chance to win.  The only real downside was Dane Swan not polling as well as I - and most other people expected - this took out a few multiple bets I'd placed, but nonetheless a multitude of other bets out there more than made up for this.

A list of all the bets that returned a profit are listed here:

• Gary Ablett to win - 75% @ $3
• Jimmy Bartel to top group comprised of Cooney, B Harvey, Deledio, Jobe Watson and Scott Thompson - 21% @ $7.5
• Bernie Vince to top group comprised of Adam Selwood, Rich, Akermanis, Hodge and Hasleby - 66% @ $2
• Fevola to top group comprised of Koschitzke, Franklin, LeCras, Pavlich and Tredrea - 75% @ $3
• Vince to top Adelaide - 53% @ $2.40
• Brown to top Brisbane 82% @ $2.2
• Winderlich to top Essendon - 17% @ $34
• Pavlich to top Fremantle - 57% @ $4
• Ablett to top Geelong - 99% at 1.12
• Richardson to top Richmond - under Any Other Player (not Deledio, Foley, Tambling, Jackson or Tuck) 49% @ $4
• LeCras to top West Coast - 34% @ 3.25

A couple of these options ended up tying with another player, effectively  halving the odds - having said that we managed to return over 50% profit on the night mainly thanks to Ablett winning and Winderlich topping Essendon at long odds.

A couple of missed opportunities were there as well - the first was Jonathan Brown to finish in the top 5 overall.  I rated him 5th in my predictions, which is exactly where he placed at massive odds of $18.  

Another was Dane Swan - he was paying $1.03 to top Collingwood's votes, whereas I rated him 91% chance, so under the odds - this represented a very nice laying opportunity where you could have taken on someone else's massive bet for a very minor risk - ie if you took $1,000 of someone's money, you would have only risked paying out $30 had Dane Swan topped Collingwood.  Turns out he didn't, so you would have pocketed the $1,000.

Still it was a very successful event overall, and in the days since I've come across a plethora of detailed player statistics that should only improve the model and it's results.  And as always, if not well we still have a model that is extremely capable.

So the only piece of AFL prediction left for the year will be the grand final, which I'll upload after the final team selections are announced.  At this stage on team form alone I'd rate Geelong slightly on top, however once we factor in the player's named this may change.  Til then.

AFL 2009 Season - Brownlow Medal Predictions

Every year for the past few years I've compiled Brownlow Medal predictions with reasonable success.  Every game I rate each player on their chance to get 3, 2, or 1 votes - then based on these probabilities I simulate the season 30,000 times in order to find the average number of votes for each player over the whole season, and their respective chance to win the medal. 

A variety of statistics are fed into the Brownlow Model - for example, each player's kicks, marks, handballs, goals, inside 50's and even the number of free kicks they give away are found to be significant predictors of how many votes they will receive.  However the two most significant predictors are the margin your team wins by, and how many Supercoach points you receive in a game.  The latter is by far the major pointer to how well a player is likely to poll, and explains why I rate Gary Ablett so highly this year, as he has by far amassed the most Supercoach points per game played.

Given that the entire season is simulated, it enables me to produce a variety predictions, not just who will win the league.  Other stats I've produced include the likelihood of there being multiple winners, how many votes the winner is likely to poll, various head to head and group propositions, and who is likely to poll the most votes for each of the teams.

One point worth noting - these predictions are all based on cold, hard, observable statistics.  There's no accounting for other reasons a player might poll well - such as being based in the midfield, having blonde hair, or being named Adam Goodes for example.  All other things being equal, a midfielder kicking for goals will likely poll higher than a forward kicking 4 goals.

So here are the predictions for this year - if there is anything else you'd like to see let me know and I should be able to work it out.  For what it's worth I rated last year's winner Adam Cooney a 15% chance to win - he paid $14 so this represents close to double what I rated him, good value indeed

Click on the link to download a spreadsheet of advanced predictions

2009 Brownlow Medal Predictions

Player	Avg Votes	% Chance
Gary Ablett	26.8	75.08%
Dane Swan	22.4	21.93%
Nick Dal Santo	18.2	4.84%
Leigh Montagna	17.8	3.56%
Jonathan Brown	15.9	0.85%
Brendon Goddard	14.1	0.64%
Paul Chapman	15.1	0.38%
Sam Mitchell	13.3	0.00%
Alan Didak	14.4	0.27%
Lenny Hayes	12.3	0.19%
Chris Judd	12.4	0.18%
Nick Riewoldt	12.1	0.17%
Marc Murphy	11.5	0.13%
Adam Goodes	12.5	0.06%
Bernie Vince	10.6	0.05%
Brendan Fevola	12.4	0.03%
Luke Power	10.2	0.03%
Matthew Boyd	9.5	0.03%
Joel Selwood	10.0	0.02%

AFL 2009 Season - Finals Week 3 Predictions

Apologies for the late posting of these, I've spent most of my free time this week getting my Brownlow Medal predictions handy, which I'll post on here shortly.

Well first off last week went according to script, firstly with the Western Bulldogs winning easily and Collingwood winning in a very close match.  Both these teams provided decent overlays as well, so profits were to be made for those betting.

I'm pretty hesitant to put the predictions up for this week, and look at the probabilities you'll soon see why, tipping both underdogs by a fairly big gap.  As has been the case with the Western Bulldogs in recent weeks, on form alone we'd rate St Kilda and Geelong on top but when the player-based aspect is added things swing in favour of the underdogs.  For what it's worth I'll be extremely happy if both of my tips are wrong, as this means St Kilda will be in the Grand Final, and more importantly Collingwood won't be.

Team 1	Team 2	Venue	Pr 1	Pr 2
St Kilda	Western Bulldogs	MCG	26.6%	71.7%
Geelong	Collingwood	MCG	20.2%	78.4%

Total tips for the season: 128 from 182 (70%)
Total tips for finals: 5 from 6 (83%)

EPL 2009/10 Season - Week 5 Predictions

Another very nice week on the tipping last week, getting 7 out of the 10 results correctly.  Currently sitting on 61% tipping success for the season, higher than I'd expected to be, so if we can keep this rate up I'll be more than happy.  A break-even week on the betting no thanks to betting on Arsenal away at Manchester City who are on the rise.

A couple of really interesting games this week - Chelsea and Manchester United at home to up and coming teams Tottenham and Manchester City - the games made even more interesting given they are both local derbies.

Date	Home Team	Away Team	Pr Home	Pr Draw	Pr Away
19/09/2009	Arsenal	Wigan Athletic	82%	12%	6%
19/09/2009	Aston Villa	Portsmouth	66%	21%	13%
19/09/2009	Bolton Wanderers	Stoke City	46%	29%	25%
19/09/2009	Burnley	Sunderland	46%	29%	25%
19/09/2009	Everton	Blackburn Rovers	62%	23%	15%
19/09/2009	Hull City	Birmingham City	38%	30%	32%
19/09/2009	West Ham United	Liverpool	15%	24%	61%
19/09/2009	Wolverhampton Wanderers	Fulham	34%	31%	36%
20/09/2009	Chelsea	Tottenham Hotspur	78%	15%	7%
20/09/2009	Manchester United	Manchester City	80%	13%	7%

Total tips for the season: 28 from 46 (61%)
Return on Investment for the season: +14%

A-League 2009/10 Season - Round 7 Predictions

Last round we tipped 2 for the 4th week in a row, getting up the first two games then missing the last 3.  Good news is we're into the top 7% on footytips, hopefully we can keeping going higher as the weeks go on.

So here are this weeks games, no real surprises as we've gone with all the home teams - tipping Adelaide and Central Coast against Melbourne and Gold Coast respectively should prove interesting.

Date	Team 1	Team 2	Venue	Pr T1	Pr Draw	Pr T2
18/09/2009	Adelaide United	Melbourne Victory	Hindmarsh Stadium	40%	27%	34%
19/09/2009	Central Coast Mariners	Gold Coast	Bluetongue Stadium	38%	27%	36%
20/09/2009	New Zealand	North Queensland	Westpac Stadium	39%	27%	34%
20/09/2009	Sydney FC	Newcastle Jets	Sydney Football Stadium	46%	26%	29%
20/09/2009	Queensland Roar	Perth Glory	Suncorp Stadium	54%	24%	22%

Total tips for the season: 13 from 30 (43%)

AFL 2009 Season - Finals Week 2 Predictions

We tipped 3 out of the 4 winners in the 1st week of the final - missing out the Western Bulldogs who I rated highly - which is the case again this week, in giving them a 92% chance against Brisbane, and again because of the profile of players selected (we'd still tip them just based on both teams' form alone for what it's worth).  The other game I rated almost a toss of the coin, tipping just in favour of Collingwood.  Any further teams changes would be interesting as this could sway the predicition in Adelaide's favour.

As a said last week I'm not using my predicstions to bet on the finals, primarily because the data I used to build the model is only using games from the home-and-away rounds.

Team 1	Team 2	Venue	Pr 1	Pr 2
Western Bulldogs	Brisbane	MCG	91.7%	7.7%
Collingwood	Adelaide	MCG	49.5%	48.4%

Total tips for the season: 126 from 180 (70%)
Total tips for finals: 3 from 4 (75%)

EPL 2009/10 Season - Week 4 Predictions

After a 2 week gap for internationals the English Premier League returns this week.  Last round we did quite well, tipping 7 out of the 10 results correctly and taking the tips to 58% for the season which is slightly ahead where'd I'd like to be by season's end, so no complaints there.

An interesting week this week, rating undefeated teams Tottenham and Manchester City as clear underdogs against Manchester United and Arsenal respectively.  The ratings for these teams haven't yet reacted to the hype surrounding them, though should these teams win against their more fancied opposition then expect their ratings so increase significantly.

Date	Home Team	Away Team	Pr Home	Pr Draw	Pr Away
12/09/2009	Blackburn Rovers	Wolverhampton Wanderers	53%	27%	20%
12/09/2009	Liverpool	Burnley	85%	10%	5%
12/09/2009	Manchester City	Arsenal	20%	27%	53%
12/09/2009	Portsmouth	Bolton Wanderers	46%	29%	25%
12/09/2009	Stoke City	Chelsea	10%	18%	72%
12/09/2009	Sunderland	Hull City	51%	28%	21%
12/09/2009	Tottenham Hotspur	Manchester United	17%	25%	57%
12/09/2009	Wigan Athletic	West Ham United	37%	30%	32%
13/09/2009	Birmingham City	Aston Villa	26%	29%	45%
13/09/2009	Fulham	Everton	32%	30%	38%

Total tips for the season: 21 from 36 (58%)
Return on Investment for the season: +23%

A-League 2009/10 Season - Round 6 Predictions

Another week of 2 tips correct out of 5, not helped by a rare week where there were 3 draws.  No real surprises this week - we're justing tipping Brisbane over Newcastle.  Interesting that the Sydney vs Nth Queensland game is being played at the Sydney Cricket Ground, no reason not to treat this as a Sydney home game.

Date	Team 1	Team 2	Venue	Pr T1	Pr Draw	Pr T2
11/09/2009	Adelaide United	Central Coast Mariners	Hindmarsh Stadium	43.4%	26.3%	30.4%
12/09/2009	Newcastle Jets	Queensland Roar	EnergyAustralia Stadium	36.5%	26.8%	36.7%
13/09/2009	Sydney FC	North Queensland	Sydney Cricket Ground	47.6%	25.5%	26.9%
14/09/2009	Melbourne Victory	New Zealand	Telstra Dome	52.3%	24.4%	23.3%
15/09/2009	Perth Glory	Gold Coast	Members Equity Stadium	33.5%	26.6%	39.9%

Total tips for the season: 11 from 25 (44%)

Super 14 Rugby Model Analysis

I managed to get hold of past Super 14 results so decided to build a quick-and-dirty model to see what we could find.  The 14-team competition started in 2006, so I've used data from 2006 through to 2008 to create the model parameters, and tested on the 2009 season.  Well, the results so far are extremely impressive - below are a couple of graphs to show how profitable this model looks.

Tipping

In the 94 games of the 2009 season the model correctly tipped 70.5 winners, which is right on 75%.  Out of the 39,000 Super 14 tippers on footytips this would have placed us somewhere between 29th and 70th overall, which is outstanding.  As with all these models though, the real fun is to see how profitable it can be.

Betting

Head to Head Betting
Firstly we'll look at the stanndard head to head betting - simply betting on the team we think will win.  As with all my betting, I've used the Kelly Criteria.  To keep things simple we'll analyse all potential bets, provided that the probability implies an advantage over the bookmaker - regardless of the size of the advantage, or the probability of the team to win.

Return on Investment

• All games: 21%
• Home Team Only: 9%
  
• Away Team Only: 32%

After an up and down start to the season (potentially due to the ratings taking a couple of weeks to stabilise),  the model showed consistent profits week after week for the rest of the season, particularly when betting on the away team to win.  More detailed analysis will more than likely show why the away teams are more profitable, but like I said this is just a quick analysis for now.

Margin Betting
A different type of betting option typically available is betting on the margin - the bookmaker will set what they expect the margin for the games to be, and then the price either side of that margin is even money.  As an example, if New South Wales host Queensland then the bookie might set the line at -6.5 points, which means NSW need to win by at least 7 points for that bet to win, otherewise if Queensland win, or even lose by 6 points or fewer then they win the bet. I tweaked the model to predict the probability of or going over and under any given margin, and from this we can bet on either side of the margin if we find an advantage over the bookie exists.

Again, we'll analyse all bets provided there is an overlay - regardless of the size of the overlay or the probability of beating the margin.

Return on Investment

• All games: 23%
• Home Team Only: -3%
  
• Away Team Only: 42%

A bit disappointing that betting on the home team to win the margin showed a slight negative profit, but that is tempered by the fact that betting on the away team to beat the margin shows over 40% ROI which is amazing.  Not sure why there is such a different profile between home and away margin betting, this will require some more time to analyse - my early thoughts are that the bookies line favour the home team more than they should, hence the bets on the away team provide more value

Improvements
Like I mentioned, this model was a quick and dirty model - I literally grabbed the data from the net and had a model built in less than hour.  As such it is a pretty simple model, with the main point is that, all other things being equal, the home ground advantage is standard throughout the comp.  That is, the ACT Brumbies face the same home ground advantage by travelling a few hours up the highway to Sydney as they would by jumping on a plane and flying across the other side of the world to play in South Africa.  The first improvemnt to make is set up separate home ground advantages based on whether the opponent is from the same country or from overseas - and then perhaps more complex home ground advtanges could be applied, for example a separate one for each team.

Secondly, in the analysis shown here no filters were put in place - we bet on all teams provided there was an overlay.  Given more time, I'll apply filters based on the size of the overlay, and the probability of winning (or beating the margin).  There's no guarantees that these improvements will results in increased profitability, but if not I can just return to the model as it appears in this report and feel fairly comfortable about its profitability in the future,.  Stay tuned.

AFL 2009 Season - Finals Week 1 Predictions

5 tips in Round 22 to round off the home-and-away season, for a final figure of 123 tips (69.9%) overall which is quite respectable for a start-up model.  As I mentioned in the season review we should only see this figure to increase when I improve the model in the off-season.

In the meantime here are my predictions for week 1 of the finals series.  No surprises for 3 of games, obviously the Cats vs Dogs game is an eye-opener with the Dogs rated so high.  Again this is down to the profile of players selected, a couple of nuances in certain players profiles sees the massive probability here.  We rated the Dogs highly in their last two game against more fancied opposition and they managed to win these, so again will be interesting to see how this game pans out.  For the record I don't think I'll be betting heavily on this game, or indeed through the finals.

Team 1	Team 2	Venue	Pr 1	Pr 2
Adelaide	Essendon	AAMI Stadium	79.3%	19.4%
Geelong	Western Bulldogs	MCG	7.9%	91.4%
Brisbane	Carlton	Gabba	78.2%	20.4%
St Kilda	Collingwood	MCG	68.7%	29.6%

Total tips for the season: 123 from 176 (69.9%)
Total tips for finals: N/A

A-League 2009/10 Season - Round 5 Predictions

Round 4 highlighted that form counts for nothing in the A-League, with undefeated Gold Coast losing away to Newcastle, and Melbourne losing away to lowly Perth. Still, the Newcastle win came on the back of a large suggested bet on them, so happy to trade-off some tips for profit.

Following are the Round 5 predictions - it's worth noting that the Central Coast vs Perth game is held in somewhat neutral Canberra. To my knowledge there hasn't been a neutral venue in the A-League before, hence I can't properly model what happens at a neutral venue. I've been able to tweek parameters though as though there is no home ground advantage, so we'll see how we go. For what it's worth, Central Coast would have been rated 46% had it been held at their home ground.

Date	Team 1	Team 2	Venue	Pr T1	Pr Draw	Pr T2
3/09/2009	Melbourne Victory	Newcastle Jets	Telstra Dome	49%	25%	26%
4/09/2009	New Zealand	Adelaide United	Westpac Stadium	37%	27%	36%
4/09/2009	Central Coast Mariners	Perth Glory	Canberra Stadium	40%	27%	34%
5/09/2009	Gold Coast	Sydney FC	Skilled Park	42%	26%	32%
5/09/2009	North Queensland	Queensland Roar	Dairy Farmers Stadium	35%	27%	39%

Total tips for the season: 9 from 20 (45%)

AFL 2009 Season - Regular Season Review

Now that the home-and-away matches have been completed I thought I'd share the overall results of the model for the year, both in terms of tipping and betting.

Tipping

The tipping did quite well for a first attempt at an AFL model - finishing on 123 tips at 69.9% success (counting both draws as 0.5 tips). The leading Herald Sun football expert finished on 122 tips, so we topped them, while Shane Warne finished on an impressive 128, no doubt buoyed by tipping St Kilda every week.

Comparing against the results from footytips.com.au (who count a draw as a whole tip, not just 0.5) - out of the 317,000 tippers we would have finished in the top 5% - 7% which again is a pretty good result for a start-up model. Hopefully some improvements to the model will only improve on this figure - more on this later.

Betting

Tipping is nice and fun and goes a long way towards bragging rights, but if a model can be used to make consistent profits then all the better. As mentioned in previous posts I follow the Kelly Criterion method of betting - which has the useful property of maximising one's exponential profit. The criteria works by finding out if the model throws up an advantage over the bookmaker (for example, if a team is rated 50% and a bookie is offering $2.20 then we have an advantage, if they are only offering $1.80 then we don't). The higher the advantage over the bookie, the more that is bet.

Two options are presented in the results below. The first shows the results had we potentially bet on every game, provided that there was an advantage over the bookie. The second option will only bet on a team if they are playing in their home state, or at a neutral venue. So in this scenario if Hawthorn played West Cost in Perth and provided a betting opportunity, we wouldn't bet on them. However if these teams played in Tasmania, then we would bet on Hawthorn as it is a neutral venue. Respected sports predictions website Sportpunter has shown in the past that betting on teams travelling interstate isn't as profitable as those playing at home or neutrally, and in fact may end up losing money. So we will present both scenarios and see if there is a significant difference.

The analysis that follows will compare various betting strategies dependent on how much we rate a team to win, and how much of an bookie's advantage (overlay) we have.

The first piece of analysis we'll look at here is betting on every game, provided there is a an advantage to be found. So regardless of how highly we rated a team, or the size of the overlay we'll bet on them - so long as there is an overlay. As mentioned, we'll compare betting on all games to just betting on home/neutral teams.

Return on Investment

• All games: 17%
• Home/Neutral Only: 25%

The return on investment is simply the amount profited (or lost) as a percentage of the total amount bet. So looking at the above graph we can see that only betting on home/neutral teams returned around $1050 profit while betting on all games returned around $900 - instantly we can see in this scenario that the bets on the teams playing interstate actually lost $150 - so the second option is better here as less money is bet (as we are not betting on interstate teams), yet profited more.

The next scenario we'll look at is to only bet on teams provided there is an overlay, and we rate them a least a certain percentage to win - in this case we'll look at 60%


Return on Investment

• All games: 25%
• Home/Neutral Only: 29%

So in this case both scenarios return around $1,100 profit, but remember that by excluding those team playing interstate we are in effect risking less money to win the same amount (hence the higher ROI).

Finally we'll look at a scenario where we only bet on a team if they have at least a certain overlay over the bookmaker. Again, any figure can be chosen - for this example we'll look at a minimum 34% overlay before we bet on a team


Return on Investment

• All games: 44%
• Home/Neutral Only: 60%

These scenarios return a little less than the previous ones, showing about $850 profit. However with this filter we have risked only half as much money as before - resulting in the massive ROI figures shown above. Also when looking at the home/neutral scenario this appears to have a nice straight-line trend throughout the year, whereas the other scenarios - while constantly growing throughout the year - appear to tail off towards the end.

Regardless of the combination of scenarios chosen, it is clear to see this model has performed exceptionally well in betting over the 2009 season.

Improvements

Despite the success of this model, there is a lot that can be improved on, which will hopefully see an uplift in both tips and profitability.

1. A portion of the model is player-based, hence I need to obtain the players that are selected on a Thursday night for that weekend's games. While I try and update the teams if any late changes are announced, for any number of reason the list of players I obtain may not be the final 22 who run out on game day - particularly for Sunday games. By going back and entering the actual players who played each game we should expect to see a slight improvement in the model's performance.
2. The player-based aspect of the model is fairly simple - I only look at the number of games played and goals kicked for the player's selected, as this info was easy to find and incorporate into the model at the time. However there is a wealth of player-based information available - for example disposals, effectiveness, time on ground, even player ratings such as SuperCoach points - so I will see if adding this information into the model will improve it significantly.
3. This model is built only using data from the 2007 and 2008 seasons, and applied to the 2009 season to arrive at the results shown on this page. By going back a few more years we should be able to bring more information into the model and hopefully improve upon the results.
4. At the moment the home ground advantage in the model is a generic one applied to the whole league. For example, all other things being even, a Melbourne team would have just as much advantage over a South Australian team as Brisbane would over a team coming from Perth. It may be beneficial to look at home ground advantage based on distance travelled, or even give each team their own home ground advantage.
5. Given the scenario above where betting on a team playing interstate isn't profitable, I may look at building two separate models - one model based on both teams being in their home state or at a neutral venue, and one where there is a team in their home state playing a team from interstate. Whether this makes a difference or not I have no idea, but the results will be interesting to see.

So there we have it. I'll still aim to publish predictions for the finals but it is worth noting that these models are only built using data from the home-and-away season so I give no guarantees for the finals. Also in the next couple of weeks I hope to publish my predictions for the Brownlow Medal.

There's probably a lot of foreign concepts introduced here so if anyone has any queries at all please don't hesitate to leave a comment and I'll get back to you.