Posts filed under Sports statistics (218)

February 25, 2015

Super 15 Predictions for Round 3

Team Ratings for Round 3

The basic method is described on my Department home page.

Here are the team ratings prior to this week’s games, along with the ratings at the start of the season.

Current Rating Rating at Season Start Difference
Crusaders 8.49 10.42 -1.90
Waratahs 8.16 10.00 -1.80
Hurricanes 4.10 2.89 1.20
Brumbies 4.07 2.20 1.90
Sharks 3.21 3.91 -0.70
Stormers 3.03 1.68 1.30
Chiefs 2.65 2.23 0.40
Bulls 1.41 2.88 -1.50
Blues 0.56 1.44 -0.90
Highlanders -2.43 -2.54 0.10
Force -3.75 -4.67 0.90
Cheetahs -4.42 -5.55 1.10
Lions -4.56 -3.39 -1.20
Reds -6.00 -4.98 -1.00
Rebels -7.52 -9.53 2.00

 

Performance So Far

So far there have been 14 matches played, 8 of which were correctly predicted, a success rate of 57.1%.

Here are the predictions for last week’s games.

Game Date Score Prediction Correct
1 Chiefs vs. Brumbies Feb 20 19 – 17 3.30 TRUE
2 Rebels vs. Waratahs Feb 20 28 – 38 -12.10 TRUE
3 Bulls vs. Hurricanes Feb 20 13 – 17 2.70 FALSE
4 Highlanders vs. Crusaders Feb 21 20 – 26 -7.10 TRUE
5 Reds vs. Force Feb 21 18 – 6 0.30 TRUE
6 Stormers vs. Blues Feb 21 27 – 16 6.30 TRUE
7 Sharks vs. Lions Feb 21 29 – 12 10.90 TRUE

 

Predictions for Round 3

Here are the predictions for Round 3. The prediction is my estimated expected points difference with a positive margin being a win to the home team, and a negative margin a win to the away team.

Game Date Winner Prediction
1 Highlanders vs. Reds Feb 27 Highlanders 8.10
2 Force vs. Hurricanes Feb 27 Hurricanes -3.40
3 Cheetahs vs. Blues Feb 27 Blues -0.50
4 Chiefs vs. Crusaders Feb 28 Crusaders -1.80
5 Rebels vs. Brumbies Feb 28 Brumbies -7.60
6 Bulls vs. Sharks Feb 28 Bulls 2.20
7 Lions vs. Stormers Feb 28 Stormers -3.60

 

February 18, 2015

Super 15 Predictions for Round 2

Team Ratings for Round 2

The basic method is described on my Department home page.

Here are the team ratings prior to this week’s games, along with the ratings at the start of the season.

Current Rating Rating at Season Start Difference
Crusaders 8.60 10.42 -1.80
Waratahs 8.35 10.00 -1.60
Brumbies 3.95 2.20 1.70
Hurricanes 3.65 2.89 0.80
Sharks 2.79 3.91 -1.10
Chiefs 2.77 2.23 0.50
Stormers 2.69 1.68 1.00
Bulls 1.87 2.88 -1.00
Blues 0.90 1.44 -0.50
Highlanders -2.54 -2.54 -0.00
Force -3.02 -4.67 1.70
Lions -4.14 -3.39 -0.80
Cheetahs -4.42 -5.55 1.10
Reds -6.73 -4.98 -1.70
Rebels -7.71 -9.53 1.80

 

Performance So Far

So far there have been 7 matches played, 2 of which were correctly predicted, a success rate of 28.6%.

Here are the predictions for last week’s games.

Game Date Score Prediction Correct
1 Crusaders vs. Rebels Feb 13 10 – 20 24.40 FALSE
2 Brumbies vs. Reds Feb 13 47 – 3 11.20 TRUE
3 Lions vs. Hurricanes Feb 13 8 – 22 -1.80 TRUE
4 Blues vs. Chiefs Feb 14 18 – 23 3.20 FALSE
5 Sharks vs. Cheetahs Feb 14 29 – 35 13.50 FALSE
6 Bulls vs. Stormers Feb 14 17 – 29 5.20 FALSE
7 Waratahs vs. Force Feb 15 13 – 25 18.70 FALSE

 

Predictions for Round 2

Here are the predictions for Round 2. The prediction is my estimated expected points difference with a positive margin being a win to the home team, and a negative margin a win to the away team.

Game Date Winner Prediction
1 Chiefs vs. Brumbies Feb 20 Chiefs 3.30
2 Rebels vs. Waratahs Feb 20 Waratahs -12.10
3 Bulls vs. Hurricanes Feb 20 Bulls 2.70
4 Highlanders vs. Crusaders Feb 21 Crusaders -7.10
5 Reds vs. Force Feb 21 Reds 0.30
6 Stormers vs. Blues Feb 21 Stormers 6.30
7 Sharks vs. Lions Feb 21 Sharks 10.90

 

February 13, 2015

Super 15 Predictions for Round 1

Team Ratings for Round 1

Sorry about the delay in posting these predictions. I have never been really happy with my selection of parameters, so decided to do a massive grid search yesterday which ended up taking about 16 hours. That means this year I have shiny new parameter values for my predictions. As ever, remember the adage, “past performance is not necessarily indicative of future behaviour”.

The basic method is described on my Department home page.

Here are the team ratings prior to this week’s games, along with the ratings at the start of the season.

Current Rating Rating at Season Start Difference
Crusaders 10.42 10.42 0.00
Waratahs 10.00 10.00 0.00
Sharks 3.91 3.91 -0.00
Hurricanes 2.89 2.89 -0.00
Bulls 2.88 2.88 0.00
Chiefs 2.23 2.23 0.00
Brumbies 2.20 2.20 -0.00
Stormers 1.68 1.68 -0.00
Blues 1.44 1.44 0.00
Highlanders -2.54 -2.54 -0.00
Lions -3.39 -3.39 -0.00
Force -4.67 -4.67 0.00
Reds -4.98 -4.98 0.00
Cheetahs -5.55 -5.55 -0.00
Rebels -9.53 -9.53 -0.00

 

Predictions for Round 1

Here are the predictions for Round 1. The prediction is my estimated expected points difference with a positive margin being a win to the home team, and a negative margin a win to the away team.

Game Date Winner Prediction
1 Crusaders vs. Rebels Feb 13 Crusaders 24.40
2 Brumbies vs. Reds Feb 13 Brumbies 11.20
3 Lions vs. Hurricanes Feb 13 Hurricanes -1.80
4 Blues vs. Chiefs Feb 14 Blues 3.20
5 Sharks vs. Cheetahs Feb 14 Sharks 13.50
6 Bulls vs. Stormers Feb 14 Bulls 5.20
7 Waratahs vs. Force Feb 15 Waratahs 18.70

 

December 20, 2014

Not enough pie

From James Lee Gilbert on Twitter, a pie chart from WXII News (Winston-Salem, North Carolina)

pie

This is from a (respectable, if pointless) poll conducted in North Carolina. As you can clearly see, half of the state favours the local team. Or, as you can clearly see from the numbers, one-third of the state does.

If you’re going to use a pie chart (which you usually shouldn’t), remember that the ‘slices of pie’ metaphor is the whole point of the design. If the slices only add up to 70%, you need to either add the “Other”/”Don’t Know”/”Refused” category, or choose a different graph.

If your graph makes it easy to confuse 1/3 and 1/2, it’s not doing its job.

October 22, 2014

Infographic of the week

From the twitter of the Financial Times, “Interactive: who is the better goalscorer, Messi or Ronaldo?”

I assume on the FT site this actually is interactive, but since they have the world’s most effective paywall, I can’t really tell.

The distortion makes the bar graph harder to read, but it doesn’t matter much since the data are all there as numbers: the graph doesn’t play any important role in conveying the information. What’s strange is that the bent graph doesn’t really resemble any feature of a football pitch, which I  would have thought would be the point of distorting it.

B0cvaNfIEAA0WZH

 

The question of who has the highest-scoring season is fairly easy to read off, but the question of “who is the better goalscorer” is a bit more difficult. Based on the data here, you’d have to say it was too close to call, but presumably there’s other information that goes into putting Messi at the top of the ‘transfer value’ list at the site where the FT got the data.

(via @economissive)

Currie Cup Predictions for the Currie Cup Final

Team Ratings for the Currie Cup Final

The basic method is described on my Department home page. I have made some changes to the methodology this year, including shrinking the ratings between seasons.

Here are the team ratings prior to this week’s games, along with the ratings at the start of the season.

Current Rating Rating at Season Start Difference
Lions 7.39 0.07 7.30
Western Province 5.87 3.43 2.40
Sharks 3.00 5.09 -2.10
Blue Bulls 1.17 -0.74 1.90
Cheetahs -3.53 0.33 -3.90
Pumas -8.20 -10.00 1.80
Griquas -10.10 -7.49 -2.60
Kings -14.91 -10.00 -4.90

 

Performance So Far

So far there have been 42 matches played, 31 of which were correctly predicted, a success rate of 73.8%.

Here are the predictions for last week’s games.

Game Date Score Prediction Correct
1 Lions vs. Sharks Oct 18 50 – 20 6.70 TRUE
2 Western Province vs. Blue Bulls Oct 18 31 – 23 10.00 TRUE

 

Predictions for the Currie Cup Final

Here are the predictions for the Currie Cup Final. The prediction is my estimated expected points difference with a positive margin being a win to the home team, and a negative margin a win to the away team.

Game Date Winner Prediction
1 Western Province vs. Lions Oct 25 Western Province 3.50

 

ITM Cup Predictions for the ITM Cup Finals

Team Ratings for the ITM Cup Finals

Here are the team ratings prior to the ITM Cup Finals, along with the ratings at the start of the season. I have created a brief description of the method I use for predicting rugby games. Go to my Department home page to see this.

Here are the team ratings prior to this week’s games, along with the ratings at the start of the season.

Current Rating Rating at Season Start Difference
Tasman 12.36 5.78 6.60
Canterbury 12.25 18.09 -5.80
Counties Manukau 6.58 2.40 4.20
Taranaki 6.27 -3.89 10.20
Auckland 4.84 4.92 -0.10
Hawke’s Bay 0.47 2.75 -2.30
Wellington -2.74 10.16 -12.90
Manawatu -2.90 -10.32 7.40
Otago -3.98 -1.45 -2.50
Northland -4.05 -8.22 4.20
Waikato -5.74 -1.20 -4.50
Southland -6.07 -5.85 -0.20
Bay of Plenty -9.23 -5.47 -3.80
North Harbour -10.13 -9.77 -0.40

 

Performance So Far

So far there have been 74 matches played, 48 of which were correctly predicted, a success rate of 64.9%.

Here are the predictions for last week’s games.

Game Date Score Prediction Correct
1 Hawke’s Bay vs. Northland Oct 17 26 – 21 9.30 TRUE
2 Manawatu vs. Southland Oct 18 23 – 18 7.70 TRUE
3 Taranaki vs. Auckland Oct 18 49 – 30 3.00 TRUE
4 Tasman vs. Canterbury Oct 18 26 – 6 1.30 TRUE

 

Predictions for the ITM Cup Finals

Here are the predictions for the ITM Cup Finals. The prediction is my estimated expected points difference with a positive margin being a win to the home team, and a negative margin a win to the away team.

Game Date Winner Prediction
1 Manawatu vs. Hawke’s Bay Oct 24 Manawatu 0.60
2 Taranaki vs. Tasman Oct 25 Tasman -2.10

 

October 15, 2014

Currie Cup Predictions for the Semi-Finals

Team Ratings for the SemiFinals

The basic method is described on my Department home page. I have made some changes to the methodology this year, including shrinking the ratings between seasons.

Here are the team ratings prior to this week’s games, along with the ratings at the start of the season.

Current Rating Rating at Season Start Difference
Lions 6.03 0.07 6.00
Western Province 6.02 3.43 2.60
Sharks 4.36 5.09 -0.70
Blue Bulls 1.02 -0.74 1.80
Cheetahs -3.53 0.33 -3.90
Pumas -8.20 -10.00 1.80
Griquas -10.10 -7.49 -2.60
Kings -14.91 -10.00 -4.90

 

Performance So Far

So far there have been 40 matches played, 29 of which were correctly predicted, a success rate of 72.5%.

Here are the predictions for last week’s games.

Game Date Score Prediction Correct
1 Kings vs. Pumas Oct 10 26 – 25 -2.20 FALSE
2 Lions vs. Cheetahs Oct 11 47 – 7 11.30 TRUE
3 Western Province vs. Sharks Oct 11 20 – 28 8.70 FALSE
4 Blue Bulls vs. Griquas Oct 11 46 – 12 13.70 TRUE

 

Predictions for the SemiFinals

Here are the predictions for the SemiFinals. The prediction is my estimated expected points difference with a positive margin being a win to the home team, and a negative margin a win to the away team


Game Date Winner Prediction
1 Lions vs. Sharks Oct 18 Lions 6.70
2 Western Province vs. Blue Bulls Oct 18 Western Province 10.00

 

ITM Cup Predictions for the ITM Cup Finals

Team Ratings for the ITM Cup Finals

Here are the team ratings prior to the ITM Cup Finals, along with the ratings at the start of the season. I have created a brief description of the method I use for predicting rugby games. Go to my Department home page to see this.

Here are the team ratings prior to this week’s games, along with the ratings at the start of the season.

Current Rating Rating at Season Start Difference
Canterbury 13.65 18.09 -4.40
Tasman 10.97 5.78 5.20
Counties Manukau 6.58 2.40 4.20
Auckland 6.05 4.92 1.10
Taranaki 5.06 -3.89 9.00
Hawke’s Bay 0.84 2.75 -1.90
Manawatu -2.66 -10.32 7.70
Wellington -2.74 10.16 -12.90
Otago -3.98 -1.45 -2.50
Northland -4.42 -8.22 3.80
Waikato -5.74 -1.20 -4.50
Southland -6.31 -5.85 -0.50
Bay of Plenty -9.23 -5.47 -3.80
North Harbour -10.13 -9.77 -0.40

 

Performance So Far

So far there have been 70 matches played, 44 of which were correctly predicted, a success rate of 62.9%.

Here are the predictions for last week’s games.

Game Date Score Prediction Correct
1 Counties Manukau vs. Auckland Oct 08 41 – 18 1.40 TRUE
2 Waikato vs. Bay of Plenty Oct 09 29 – 12 5.70 TRUE
3 Otago vs. Manawatu Oct 10 25 – 38 5.40 FALSE
4 Wellington vs. North Harbour Oct 11 58 – 34 9.10 TRUE
5 Hawke’s Bay vs. Southland Oct 11 20 – 20 13.20 FALSE
6 Auckland vs. Northland Oct 11 38 – 10 13.60 TRUE
7 Taranaki vs. Canterbury Oct 12 23 – 26 -5.00 TRUE
8 Tasman vs. Counties Manukau Oct 12 16 – 21 12.40 FALSE

 

Predictions for the ITM Cup Finals

Here are the predictions for the ITM Cup Finals. The prediction is my estimated expected points difference with a positive margin being a win to the home team, and a negative margin a win to the away team.

Game Date Winner Prediction
1 Hawke’s Bay vs. Northland Oct 17 Hawke’s Bay 9.30
2 Manawatu vs. Southland Oct 18 Manawatu 7.70
3 Taranaki vs. Auckland Oct 18 Taranaki 3.00
4 Tasman vs. Canterbury Oct 18 Tasman 1.30

 

October 7, 2014

Currie Cup Predictions for Round 10

Team Ratings for Round 10

The basic method is described on my Department home page. I have made some changes to the methodology this year, including shrinking the ratings between seasons.

Here are the team ratings prior to this week’s games, along with the ratings at the start of the season.

Current Rating Rating at Season Start Difference
Western Province 7.02 3.43 3.60
Lions 4.39 0.07 4.30
Sharks 3.35 5.09 -1.70
Blue Bulls -0.18 -0.74 0.60
Cheetahs -1.89 0.33 -2.20
Pumas -7.97 -10.00 2.00
Griquas -8.90 -7.49 -1.40
Kings -15.13 -10.00 -5.10

 

Performance So Far

So far there have been 36 matches played, 27 of which were correctly predicted, a success rate of 75%.

Here are the predictions for last week’s games.

Game Date Score Prediction Correct
1 Sharks vs. Lions Oct 03 26 – 23 4.10 TRUE
2 Pumas vs. Blue Bulls Oct 03 6 – 37 0.80 FALSE
3 Cheetahs vs. Western Province Oct 04 29 – 34 -3.70 TRUE
4 Griquas vs. Kings Oct 04 45 – 25 10.00 TRUE

 

Predictions for Round 10

Here are the predictions for Round 10. The prediction is my estimated expected points difference with a positive margin being a win to the home team, and a negative margin a win to the away team.

Game Date Winner Prediction
1 Kings vs. Pumas Oct 10 Pumas -2.20
2 Lions vs. Cheetahs Oct 11 Lions 11.30
3 Western Province vs. Sharks Oct 11 Western Province 8.70
4 Blue Bulls vs. Griquas Oct 11 Blue Bulls 13.70