THE POWER RANK

New international football / soccer rankings show recent form of nations

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world_soccer_June19_2014The FIFA rankings suck. Not only do they poorly predict the outcome of matches, but you have to wait a month for updates.

The Power Rank international football / soccer rankings do better. The ranking algorithm considers margin of victory in adjusting for schedule strength in international soccer. As an academic study has shown, using margin of victory is critical in making predictions.

In addition, the international rankings are now updated daily.

This constant updating is interesting during the World Cup. My rankings use a 4 year window of matches and weight matches by their importance.

  • World Cup Finals: 4.
  • World Cup Qualifiers, Confederations Cup, Continental Finals: 3.
  • Continental Qualifiers, 2.
  • Friendlies, 1.

Since we’re in the middle of a World Cup, the rankings add important matches each day while dropping results from the previous World Cup. This leads to some interesting changes for certain teams.

Spain and the Netherlands

The Netherlands dominated Spain in a 5-1 win last week. This dropped an aging Spain team down to 6th. The FIFA rankings still have Spain as the top team.

The Dutch have risen to 4th. It mystifies me why more people didn’t think this traditional power could win this World Cup.

Germany and Brazil

While most other respectable rankings have Brazil on top, the weighting of matches in The Power Rank vaults Germany ahead of Brazil.

Germany has played well in the last two World Cups. In 2010, they dominated Argentina in a 4-0 rout. Just last week, they beat Portugal, another top 10 team, by the same margin.

With no weighting, Brazil would be the top team in The Power Rank.

United States and Ghana

The Yanks are 18th currently, one spot above the Ghana squad they just beat.

The United States won the game because of two great finishes by Clint Dempsey and John Brooks. However, between these two goals, Ghana dominated possession and scoring opportunities. They were the better team.

Colombia and Chile

These two South American teams are in the top 10. Colombia is ranked higher at 5th, but Chile is not far behind at 7th.

From this World Cup, the Colombia looks like the better team. They continue to score goals despite the absence of Radamel Falcao, their leading scorer in qualifying.

Moreover, my aggregated win probabilities before the World Cup gave Colombia an almost 4% chance to win it all. Chile only had a 1.9% chance.

Belgium and France

Belgium has generated much chatter as a dark horse World Cup champion. Young players like Eden Hazard have dazzled on the pitch at this World Cup.

However, their performance over the last 4 years ranks them 13th in The Power Rank. That puts them lower than France (9th), a team no has talked about as World Cup champion. (Of course, France is missing star winger Frank Ribery for this World Cup.)

Belgium’s play as a team does not make me believe they will contend for the World Cup title. My aggregated win probabilities before the tourney agree with this assessment. Belgium had the 11th highest win probability at 2.3%.

Rankings of World Cup teams

Here are rankings of the 32 World Cup teams that consider matches from June 20, 2010 through June 19, 2014. The record gives wins, losses and ties over the past 4 years. The rating gives an expected margin of victory against an average international team.

1. Germany, (37-7-11), 2.52
2. Brazil, (40-9-12), 2.28
3. Argentina, (32-8-15), 2.15
4. Netherlands, (33-9-11), 2.09
5. Colombia, (24-8-11), 2.09
6. Spain, (45-8-8), 2.05
7. Chile, (29-17-9), 1.69
8. Uruguay, (28-14-15), 1.69
9. France, (28-11-12), 1.59
10. Portugal, (26-9-13), 1.54
11. Ecuador, (17-14-15), 1.48
12. Mexico, (35-18-17), 1.48
13. Belgium, (22-8-12), 1.44
14. England, (25-8-14), 1.43
15. Ivory Coast, (31-7-9), 1.42
16. Italy, (22-12-21), 1.40
17. Ghana, (30-15-14), 1.29
18. United States, (37-17-12), 1.25
19. Russia, (24-6-13), 1.25
21. Switzerland, (20-7-12), 1.23
23. Croatia, (24-10-11), 1.16
24. Nigeria, (29-11-21), 1.11
27. Japan, (33-12-13), 1.07
28. Bosnia-Herzegovina, (21-14-7), 1.03
30. Costa Rica, (25-23-19), 0.95
32. Greece, (24-8-16), 0.91
34. Australia, (26-16-11), 0.87
35. Iran, (30-8-16), 0.85
38. South Korea, (24-17-12), 0.80
43. Honduras, (22-24-18), 0.75
50. Cameroon, (16-13-12), 0.60
53. Algeria, (19-10-6), 0.56

For all teams, click here.

Predictions

The Power Rank also provides predictions for each match and stages of the competition, both of which are update nightly.

These predictions use a different set of rankings that consider a 12 year window of games. Research as shown that these calculations are as accurate in predicting match outcomes as using a 4 year window.

What are Germany’s odds of winning Euro 2012 now that they own the Group of Death?

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For updated win probabilities for Euro 2012, click here to view our interactive bracket.

Group of Death

Germany marches on while the Netherlands lingers on the brink of Euro death. Since the Germans are almost certain to make the knock out stage (92%), they now have the highest chance of winning Euro 2012 at 24%. This is higher than Spain’s odds at 20%. The Netherlands now need Denmark to lose to Germany and then beat Portugal by a bunch of goals. It’s still possible. 9.7% possible.

Croatia is ranked 8th in the FIFA rankings?

When we mentioned that Croatia was the worst team in Euro 2012, Morgan kindly pointed out their lofty status in those other rankings. A big reason why Croatia lands at 35th in our rankings are two World Cup qualifying games with England. Croatia lost 9-2 on aggregate in this home and home series. In rankings without those two games, Croatia jumps up to 22nd. (England drops from 9th to 17th.) Moreover, Croatia didn’t astound anyone in a Euro qualifying group with Latvia (85), Georgia (95), and Malta (114). They even lost to Georgia.

Croatia faces a serious test in Italy tomorrow morning.

Home field advantage.

We use a home field advantage of 0.41 goals for Poland and Ukraine, since this was the average advantage over all qualifying matches for Euro 2012. Greg asked why we used all qualifying games instead of only games with teams that qualified.

Great question. First, there are only 248 games in qualifying. Eliminating any of those games reduces our sample size, which reduces the accuracy with which we can calculate home advantage.

Second, the objective is to determine the advantage of playing at home, no matter what the strength of the teams. We’re interested in Luxembourg just as much as Germany. Fortunately, the home and home structure of fixtures between any two teams in qualifying really helps. If Germany only played San Marino at home, they would, on average, win by more than 6 goals. This would seriously skew the estimate for home advantage. But since Germany plays a home and home with San Marino, they might win by 7 goals at home but only 5 goals on the road. In our calculation of home advantage, the large positive goal differential at home for Germany is negated by the large negative goal differential for San Marino at home. This leaves a clean estimate for home advantage when one European country travels to another.

What do you think?

Do the Dutch have a chance? Does Croatia’s play on the pitch seem like that of a top 10 team? Please leave us a comment.

Thanks for reading.

How far did the Netherlands’ win probability drop after Day 1 of the Group of Death, Euro 2012?

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Euro 2012 favorite Germany survived its first match in the Group of Death.

Euro 2012 favorite the Netherlands didn’t.

To see update win probabilities for Euro 2012 after Day 2, click here. Here are three thoughts from the day.

1. Sometimes the better team doesn’t win.

The Netherlands was dominating the first half against Denmark. The Danes could barely possess the ball against one of the most skilled teams in the world. Then, a lucky bounce brings the ball right to Denmark’s Michael Krohn-Dheli at the top of the box. He dribbles in and slots the ball right through the goalkeeper’s legs. Denmark wins the game 1-0.

The Power Rank calculates win probabilities for Euro 2012.With the win, Denmark’s chance to make the knock out phase jumps from 38% to 67%. They now have a 8.9% chance of winning Euro 2012, which makes the 66-1 odds at the sports book before the tourney seem even more ridiculous. The loss drops the Netherlands’ probability of escaping the Group of Death from 62% to 34%. Their probability of winning Euro 2012 drops from 15.4% to 8.2%.

2. George McFly scores for Germany.

Mario Gomez was terrible in the Champion’s League final. The center forward for Bayern Munich, who Grant Wahl of SI aptly called the George McFly of soccer, couldn’t do anything against Chelsea. For Germany, Gomez scored the only goal of the game against Portugal, heading a ball a down and in the corner of the net. (If only Americans could learn to head the ball down. Yes, I’m talking about you, Clarence Goodson.) Pre tourney favorite Germany increased their probability of winning Euro 2012 from 13.5% to 18%. Portugal drops from 40% to 23% to make it out of the Group of Death.

3. Back to the beautiful game for the Dutch

For a country that usually plays such beautiful football, the Netherlands went street on Spain in the World Cup final in 2010. The Dutch played a rough game to slow the Spanish passing game down. They were like the 1994 New York Knicks, with Mark Van Bommel as Anthony Mason.

At Euro 2012, they’ve returned to beautiful football. Their brief sojourn to the dark side should be seen as a tribute to Spain. The Spanish are so talented that a top 5 team in talent has to resort to kicking them in the shins.

Thanks for reading. And please do check out the updated interactive bracket here.

Check out our interactive bracket for Euro 2012

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To play with our interactive bracket, click here.

Who will win Euro 2012?

The talking heads on sports media will certainly share their opinion based on gut instinct. But wouldn’t it be cool to have a card counter’s edge in knowing who will win? An unbiased estimate of the win probability for all 16 teams?

The Power Rank algorithm is used to rank teams and simulate Euro 2012 half a million times.At The Power Rank, we crunch numbers to predict the outcome of tournaments. It begins with our algorithm for ranking teams, which has been more accurate than Vegas at predicting winners of college football bowl games. Then, we use these rankings to simulate Euro 2012 half a million times. Just like the mathematicians who used simulations to beat black jack, we analyze these results to provide a fresh perspective. Perhaps it’s a new view to share with your soccer fanatic friends.

If Poisson random variables means something to you, there’s a description of our methods at the bottom of this post. For everyone else, click here to see all of our predictions. Here, we’ll supplement the bracket with analysis of some important questions.

Who will win Euro 2012?

Spain, the Netherlands and Germany are the three best teams in this tourney. Not many will argue with that. As one can see from hovering over the right most circle in the interactive bracket, these teams have the highest likelihoods of winning the tourney. However, Spain has a much easier route. The Netherlands and Germany occupy the Group of Death with Portugal and Denmark, two other top 12 teams in our world rankings. Spain has a 23.1% chance of winning, a significantly higher likelihood than the Netherlands and Germany at 15.2% and 13.6% respectively.

Still, a 23% win probability is not that large. If each team had an equal likelihood of winning Euro 2012, the win probability would be 6.25%. Spain is 3.7 times more likely to win the tourney. In this year’s NCAA men’s basketball tournament, the University of Kentucky had a 16% chance of winning. This is 10.9 times greater than the 1.5% probability assuming all 68 teams are equal. The European Football Championships are insanely competitive.

Who will survive the Group of Death?

The Netherlands (3), Germany (4), Portugal (7) and Denmark (12) are all in the same group. Just brutal. In comparison, Group A has Russia (20), Czech Republic (24), Greece (42) and Poland (44). This makes it the Group of Eternal Life. While the Netherlands and Germany have about a 60% chance of making it to the knock out stage, Denmark still has a 38% chance.

The strength of this group is even more apparent from the tournament win probabilities. Denmark and Portugal both have about a 5% chance to win Euro 2012, a higher likelihood than any team from the Group of Eternal Life.

How will the host countries Poland and Ukraine do?

These two host countries present a problem for our rankings since they did not have to qualify for Euro 2012. We only use meaningful games such as tournaments and qualifying games to rank teams. This leaves us with only 10 and 12 games to evaluate Poland and Ukraine respectively since 2009. These games were from a failed World Cup qualifying campaign for both countries.

To see whether these countries had performed better lately, we considered friendlies involving Poland and Ukraine since the last World Cup. We added these matches to the set of matches used in our rankings. While the team ranking for the Ukraine barely changed from 31st to 32nd, Poland shot up from 96th to 44th. They’re still essentially the worst team in the tourney, but they’re no longer the 2012 Charlotte Bobcats of the NBA. Poland has clearly performed much better since their failed World Cup qualifying campaign, earning ties against full strength squads from Germany and Mexico.

There are many problems with using friendlies in our rankings. As readers of this site have pointed out, the rules are different (6 substitutions instead of 3), and teams treat these games as exhibitions to try new strategies. However, Poland and Ukraine probably treated these games more seriously since they didn’t have to qualify for Euro 2012. Moreover, the jump in Poland’s ranking is too large to ignore. We decided to use these additional games in our Euro 2012 simulations. With a 0.41 goal advantage as a host country, Poland and Ukraine have a 56% and 53% probability respectively to advance past the group stage.

Note: We have not used the friendlies for Poland and Ukraine in the primary world rankings. Sorry for the confusion, as the rankings on the interactive bracket do not match these rankings.

How did we perform these simulations?

The win probabilities in the interactive bracket are based on The Power Rank algorithm, a method that accounts for strength of schedule and margin of victory in ranking teams. While our team rankings show team strength for 119 countries, we take a different approach to generate win probabilities for Euro 2012. Instead of applying the algorithm to the entire team, we apply it to the offensive and defense separately. This leads to a goal rate for one team’s offense against another’s defense.

From here, we simulate the score of each game in the group round. The score comes from two uncorrelated Poisson random variables based on the goal rates. Moreover, the goals scored and allowed for each team lets us account for tie breakers in each simulation. The Poisson model also applies in the knock out stage. In the unfortunate case a game ends tied after 120 minutes, we pick randomly to determine a winner. Unfortunately, we don’t have the data or analytics to make a better guess about the outcome of a penalty kicks.

What do you think?

Is Poland really that good? Will you completely ignore these predictions because it includes friendlies for Poland and Ukraine? Please leave us a comment.

Thanks for reading.

What Everybody Ought to Know About World Football / Soccer

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The FIFA rankings are terrible.

Behind the disguise of weighting factors and other funny math, the FIFA rankings are a table of results. Win a match, get 3 points. Draw a match, earn 1 point. Attempt to adjust for strength of competition and divide by the number of games played, and you have a rating for each country.

But tables are misleading. For example, Newcastle finished 5th in the English Premier League. However, they scored only 5 more goals than they allowed, only 8th best among 20 teams. Goal differential is predictive of team strength, so Newcastle got a bit lucky this year.

At least in the Premier league, each team plays every other team twice. Tables are even more misleading in world football since countries play schedules of differing strength.

Rankings for World Football / Soccer Teams by The Power Rank algorithmHere at The Power Rank, we have developed better ranking system based on years of research in statistical physics. Instead of counting up points for wins and ties, we solve a set of linear equations, the bedrock operation in modern data mining. Moreover, our algorithm accounts for margin of victory and strength of schedule in ranking countries. Using all major international competitions since 2009, our algorithm assigns each team a rating, which gives a team’s strength in goals compared to the average international team. So Spain’s 2.0 rating says they will beat the average team (Belgium) by 2 goals on average at a neutral site.

While we haven’t tested these predictions on international football yet, the predictions for American college football work quite well. Over the last 10 years of college football bowl games (late season games played at neutral sites), the rankings have predicted more game winners, 62.4%, than the Vegas betting line, 61.7%. This sample includes 314 games.

For world soccer, the rankings reveal some hidden truths that everyone ought to know.

Brazil is the best team in the world

They haven’t done so well in their last two major competitions. The Brazilians exited the World Cup in 2010 in the quarterfinals against the Netherlands. Coach Dunga left after this debacle. Then in last year’s Copa America, Brazil lost to Paraguay in the quarterfinals.

However, our algorithm still thinks highly of Brazil due to their consistent track record of success. They won the Confederation’s Cup in 2009. More importantly, they finished first in World Cup qualifying out of South America, a brutal stretch of 18 games against some of the best teams in the world. Lastly, tournament soccer leaves even the best teams in the world subject to random chance. Brazil lost to the Netherlands on a freak own goal by Felipe Melo. Their exit in Copa America came in penalty kicks after a 0-0 draw.

Let’s contrast Brazil with Uruguay, the 5th best team in the world. Uruguay had more success than Brazil in the World Cup (4th place) and Copa America (winner). However, they finished 5th in World Cup qualifying in South America, 10 points back of Brazil. Uruguay had to win a playoff against Costa Rica just to make the World Cup.

And then no one will ever forgot the luck bestowed upon Uruguay against Ghana in the World Cup. Tied late in the quarterfinal game, Uruguayian striker Luis Suarez intentionally blocks a sure goal with his hand. Then Ghana’s Asamoah Gyan missed the ensuing penalty kick, allowing Uruguay to win the game in penalty kicks. Watch it again here.

We mean no disrespect to Uruguay. It takes incredible talent and work to earn the 5th spot in these rankings. However, Brazil is the better team.

Is the United States better than Mexico?

Well, no. The Power Rank puts Mexico at 12th, while the United States comes in at 22nd.

However, this distinction rests on a single game. In 2009, the United States went to the Confederations Cup in South Africa. That summer also featured the Gold Cup, the North American championship held every two years. While the Americans sent their first team to South Africa, they played a reserve unit on home soil in the Gold Cup. The reserves played very well, making it all the way to the final against Mexico. Even through halftime, the championship remained tied at 0.

Then the wheels came off for the Americans. Mexico, who played first teamers like Gio Dos Santos and Gerardo Terrado, scored 5 goals in the second half. The U.S. line up featured Jay Heaps and Brian Ching, players who would not make the 2010 World Cup squad.

If we do not include games from the 2009 Gold Cup, the United States and Mexico are ranked 18th and 19th respectively. Clearly, better rankings would account for situations in which one team doesn’t play their first team. For now, we’re treating all international matches the same.

Who is the best team in Europe?

Spain and the Netherlands are 2nd and 3rd in the rankings, separated by less than a hundredth of a goal. Essentially, our algorithm does not make a distinction between these two teams. The finals of Euro 2012 could quite possibly be a rematch of the World Cup final two years ago.

Next week, we’ll reveal the full rankings and discuss how to use our algorithm to project the entire bracket for Euro 2012. If you’re interested in this, please follow The Power Rank on Twitter.

What do you think?

We would love to hear from you. Are there other games like the 2009 Gold Cup final in which one team didn’t play their first team? How necessary is it to include friendly matches in these rankings? Please leave us a comment.

Thanks for reading.