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Collingwood +9 v Brisbane
Richmond +17 v North Melbourne
Gold Coast v Carlton +10
GWS +24 v Essendon
St Kilda v Geelong +10
Adelaide +17 v Sydney
Western Bulldogs +67 v West Coast
Melbourne +17 v Hawthorn
Fremantle v Port Adelaide +1

5/9, 141/198

1. Carlton 16.49
2. Brisbane 15.59 (+3)
3. Melbourne 13.11 (+1)
4. Adelaide 12.28 (-1)
5. GWS 11.62 (+5)
6. Collingwood 11.41 (-4)
7. Port Adelaide 10.67 (+1)
8. Sydney 10.04 (+1)
9. Geelong 5.55 (-3)
10. St Kilda 5.43 (+1)
11. Western Bulldogs 2.15 (-4)
12. Gold Coast 1.75
13. Fremantle -4.59
14. Hawthorn -5.83
15. Richmond -7.76
16. Essendon -18.7
17. North Melbourne -25.93
18. West Coast -38.37

With one match to play, the ladder tips are kind of moot.

Essendon v Collingwood +30
Hawthorn +11 v Fremantle
North Melbourne v Gold Coast +24
Brisbane +16 v St Kilda
Geelong +3 v Western Bulldogs
West Coast v Adelaide +39
Port Adelaide +31 v Richmond
Sydney +3 v Melbourne (assuming an umpiring howler that gifts them the win)
Carlton +11 v GWS

If my tips are right, the ladder going into the finals will be

Collingwood 18
Brisbane 17
Port Adelaide 17
Melbourne 15
Carlton 14.5
Sydney 13.5
St Kilda 13
GWS 12
Geelong 11.5
Adelaide 11
Bulldogs 11
Essendon 11
Gold Coast 10
Fremantle 9
Hawthorn 8
West Coast 3
North Melbourne 2
 
Essendon v Collingwood +30
Hawthorn +11 v Fremantle
North Melbourne v Gold Coast +24
Brisbane +16 v St Kilda
Geelong +3 v Western Bulldogs
West Coast v Adelaide +39
Port Adelaide +31 v Richmond
Sydney +3 v Melbourne (assuming an umpiring howler that gifts them the win)
Carlton +11 v GWS

4/9. 145/207

I include a phantom week for the break, which tends to neutralize ratings a little.

1. Collingwood 13.88 (+5)
2. GWS 13.48 (+3)
3. Brisbane 13.18 (-1)
4. Melbourne 13.15 (-1)
5. (Adelaide 11.19) (-1)
6. Carlton 10.31 (-5)
7. Port Adelaide 9.73
8. Sydney 6.85
9. (Western Bulldogs 6.19) (+2)
10. St Kilda 4.35

Collingwood +1 v Melbourne
Carlton +9 v Sydney
St Kilda v GWS +3
Brisbane +15 v Port Adelaide
 
Collingwood +1 v Melbourne
Carlton +9 v Sydney
St Kilda v GWS +3
Brisbane +15 v Port Adelaide

4/4, 149/211

1. Brisbane 16.79 (+2)
2. GWS 16.21
3. Collingwood 15.2 (-2)
4. Melbourne 13.64
5. (Adelaide 11.19)
6. Carlton 10.76
7. (Sydney 8.18) (+1)
8. Port Adelaide 7.52 (-1)

Melbourne +3 v Carlton
Port Adelaide +3 v GWS
 

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Melbourne +3 v Carlton
Port Adelaide +3 v GWS

0/2, 149/213. Since the computer didn't think there was much in it, I don't feel badly about this.

1. GWS 19.28 (+1)
2. Brisbane 15.24 (-1)
3. Collingwood 13.7
4. (Melbourne 13.15)
5. Carlton 11.74 (+1)
6. (Adelaide 10.32) (-1)
7. (Sydney 7.69)
8. (Western Bulldogs 5.38) (+1)
9. (Port Adelaide 5.00) (-1)

Collingwood +1 v GWS
Brisbane +10 v Carlton
 
I'm attempting to revive the algorithm. I've made a few changes and I'll see how it pans out.

I'm not recalculating old results - this results in recursion issues and plays havoc with my spreadsheet.

Teams will have a rating which reflects an expected result against an average team on a neutral ground. Home ground advantage is assessed as two goals for interstate match-ups, nothing for intra-state. The Grand Final is considered neutral. The predicted result will be your current rating, minus the other team's current rating, and the home state bonus.

When assessing a result, I shrink results over 50 points (by half of the amount over 50) and add/subtract the home-ground bonus, and then add the opponents' rating before the game. So, a +20 win at home against an interstate team with a rating of -5 would be valued at +3. Away, it would be rated at +27.

I consider Tasmanian venues as home ground for Hawthorn/North Melbourne against interstate teams. I'll have to check if they play any Victorian teams there to see whether I need to make a decision. Other matches played outside the home team's home state will be considered neutral.

I'm currently degrading results at a regular rate, and I'm trying varying rates of degradation from 10% to 20%. I'll see which one has the best predictive rate so far this season. (So far, it only matters for roughly one match per round). In theory, old matches can continue to count toward current predictions forever. I've only entered results from the beginning of last year. With (functionally) 30 rounds in a season, including the opening round, break before the finals, and four weeks of finals, at 10% it takes 96% of its rating from the last year, and over 99% at 15% or 20%. After 13 rounds this year, 77-96% of the current ratings are taken from this year alone.

For long-term ladder predictions, I add the predicted margin to 50%, capping at 95%/5%. So, if I predict a 20 point win, I think the team will win 70% of the time. I'm applying the degradation for future tips so that projections for later in the season will be weaker - margins will shrink and predictions will tend to favour the home team a bit more.

I won't predict draws - if that's the predicted result, I'll drag it out to a 1 point tip for whichever side is rated slightly better.

Currently, with 10% degradation, the ratings are:

Collingwood 23.4
Geelong 21.4
Adelaide 20.4
Bulldogs 19.5
Brisbane 11.8
Fremantle 8.7
Gold Coast 7.9
Hawthorn 6.5
GWS 3.0
Carlton 1.1
St Kilda -4.5
Sydney -8.1
Melbourne -8.4
Essendon -9.56
Port Adelaide -9.59
North Melbourne -16.0
Richmond -22.6
West Coast -25.8

And the predicted ladder is something like this (with fractional wins)

Collingwood 17.26
Geelong 15.23
Brisbane 15.15
Adelaide 14.77
Gold Coast 14.21
Bulldogs 13.66
Fremantle 13.24
GWS 12.72
Hawthorn 12.37
Essendon 10.87
Carlton 10.39
St Kilda 9.78
Melbourne 9.43
Port Adelaide 9.32
Sydney 9.19
North Melbourne 7.48
Richmond 6.77
West Coast 5.13

If I just take the favourite for each match, we end up with:

Collingwood 19
Adelaide 17
Bulldogs 17
Geelong 17
Brisbane 15.5
GWS 14
Fremantle 14
Gold Coast 13
Hawthorn 12
Carlton 12
St Kilda 10
Port Adelaide 10
Sydney 9
Essendon 9
Melbourne 7
North Melbourne 5.5
Richmond 3
 
Last edited:
I'm attempting to revive the algorithm. I've made a few changes and I'll see how it pans out.

I'm not recalculating old results - this results in recursion issues and plays havoc with my spreadsheet.

Teams will have a rating which reflects an expected result against an average team on a neutral ground. Home ground advantage is assessed as two goals for interstate match-ups, nothing for intra-state. The Grand Final is considered neutral. The predicted result will be your current rating, minus the other team's current rating, and the home state bonus.

When assessing a result, I shrink results over 50 points (by half of the amount over 50) and add/subtract the home-ground bonus, and then add the opponents' rating before the game. So, a +20 win at home against an interstate team with a rating of -5 would be valued at +3. Away, it would be rated at +27.

I consider Tasmanian venues as home ground for Hawthorn/North Melbourne against interstate teams. I'll have to check if they play any Victorian teams there to see whether I need to make a decision. Other matches played outside the home team's home state will be considered neutral.

I'm currently degrading results at a regular rate, and I'm trying varying rates of degradation from 10% to 20%. I'll see which one has the best predictive rate so far this season. (So far, it only matters for roughly one match per round). In theory, old matches can continue to count toward current predictions forever. I've only entered results from the beginning of last year. With (functionally) 30 rounds in a season, including the opening round, break before the finals, and four weeks of finals, at 10% it takes 96% of its rating from the last year, and over 99% at 15% or 20%. After 13 rounds this year, 77-96% of the current ratings are taken from this year alone.

For long-term ladder predictions, I add the predicted margin to 50%, capping at 95%/5%. So, if I predict a 20 point win, I think the team will win 70% of the time. I'm applying the degradation for future tips so that projections for later in the season will be weaker - margins will shrink and predictions will tend to favour the home team a bit more.

I won't predict draws - if that's the predicted result, I'll drag it out to a 1 point tip for whichever side is rated slightly better.

Currently, with 10% degradation, the ratings are:

Collingwood 23.4
Geelong 21.4
Adelaide 20.4
Bulldogs 19.5
Brisbane 11.8
Fremantle 8.7
Gold Coast 7.9
Hawthorn 6.5
GWS 3.0
Carlton 1.1
St Kilda -4.5
Sydney -8.1
Melbourne -8.4
Essendon -9.56
Port Adelaide -9.59
North Melbourne -16.0
Richmond -22.6
West Coast -25.8

And the predicted ladder is something like this (with fractional wins)

Collingwood 17.26
Geelong 15.23
Brisbane 15.15
Adelaide 14.77
Bulldogs 13.66
Gold Coast 13.53
Fremantle 13.24
GWS 12.72
Hawthorn 12.37
Essendon 10.54
Carlton 10.39
St Kilda 9.78
Melbourne 9.43
Port Adelaide 9.32
Sydney 9.19
North Melbourne 7.48
Richmond 6.77
West Coast 5.13

If I just take the favourite for each match, we end up with:
The Dogs run home seems easy on paper. Your model has them bunched up much closer either the 2 teams below than the top 4 entry barrier.

That's the most interesting thing that jumped out. I agree with Adelaide being a massive top 4 threat though.
 
The Dogs run home seems easy on paper. Your model has them bunched up much closer either the 2 teams below than the top 4 entry barrier.

That's the most interesting thing that jumped out. I agree with Adelaide being a massive top 4 threat though.
An effect of applying the rating degradation to future matches is that, for example, a rating of about 20 now is worth about 5 by round 24. It won't effect the win-loss predictions for teams in the same state, but it will shrink the predicted margin (which affects the first ladder).

A good team that holds its current form will exceed these predictions.

The Bulldogs' good run home is made more clear by the "favourites win" ladder.
 
An effect of applying the rating degradation to future matches is that, for example, a rating of about 20 now is worth about 5 by round 24. It won't effect the win-loss predictions for teams in the same state, but it will shrink the predicted margin (which affects the first ladder).

A good team that holds its current form will exceed these predictions.

The Bulldogs' good run home is made more clear by the "favourites win" ladder.
Ah, the favourites ladder wasn't attached when I posted. Yes, that has the Dogs up in the top 4. Either way, bullish predictions for Adelaide.
 

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