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.

3 thoughts before Spain and Italy in the Euro 2012 Finals

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The Power Rank predictions for who will win Euro 2012I’m frequently at Tootsie’s, an Italian restaurant and cafe at the Stanford Barn with amazing food. When I asked the owner Rocco about Italy before the start of Euro 2012, he said, “We suck”. After Italy tied Spain in the first game, he proclaimed, “We’re going to win Euro.” When I told him Italy had a 36% chance to advance over Germany in the semifinals, he kicked me out. Well, no, but Rocco reflects the optimism of Italy as they face Spain in the final fixture of Euro 2012. The Power Rank gives Italy a 37% to win Euro 2012 over Spain.

Let’s break this down further, shall we?

What assumptions go into this win probability?

This prediction involve three steps. First, we use our core algorithm to rank the offense and defense of each country. Second, we employ these rankings to generate goal rates for Spain against Italy and vice versa. Third, we plug these goal rates into a model to get a score, both at the end of regular time and over time. In this model, we assume the goals scored by each team are independent of each other.

Well, the goals for two teams in a match are not independent. If they were, we would find that the correlation coefficient between the goals for the home and away teams in Euro qualifying is zero. It’s not. The correlation coefficient is -0.26. This implies that if one team scores a lot of goals, the other team tends to score fewer goals. The Wikipedia page for correlation coefficient has some nice pictures of what a plot of home versus away goals might look like.

From a soccer perspective, this negative correlation coefficient could mean that teams play more defensively when they take a lead. With match details beyond the final score, one could determine if goals rates are different based on the score. If so, that suggests a better probabilistic model for the final score than the independent Poisson random variables we use now.

If the game goes to penalty kicks, we flip a coin. Spain and Italy would then have a 50% chance to win Euro 2012. This model seems consistent with popular opinion, as an ESPN commentator has talked about the complete randomness of penalty kicks. Moreover, it’s difficult to imagine a better model since there is such little penalty kick data for each player.

Will Spain score against Italy?

In our rankings, Spain has the 4th best offense in the world. We predict they would score 2.16 goals against an average defense. However, this goal rate probably depends on who plays up top. When Ferrando Torres enters the game, the Spanish game transitions from a crisp passing game to an offense interrupted by offsides penalties on Torres. Spain plays much better with Cesc Fabregas at this attacking position.

Our ranking have Italy as the 25th defense in the world, despite giving up only 0.71 goals in meaningful competition since the start of World Cup 2010 qualifying. Our methods predict they would concede 0.79 goals to an average offense. However, Italy’s rating might suffer from weak competition in European qualifying matches. You can’t concede less than 0 goals to the Faroe Islands, the 107th best offense in the world. Italy’s defense features 3 defenders from a Juventus team that allowed only 0.53 goals per game in Serie A.

Will Italy score on Spain?

While Mario Balotelli has received most of the attention after his 2 goals against Germany, play maker Riccardo Montolivo is the key to this Italian offense. He made the pass found Balotelli behind the German defense for his second goal. Moreover, Montolivo made a number of incredible passes against England that led to missed goals for the Italians. Italy has the 17th best offense, predicted to score 1.76 goals against average international competition.

However, they face a stout Spainish defense, 3rd best in the world with a 0.44 rating. The Spanish haven’t conceded a goal since Italy’s Antonio Di Natale scored in the first match of Euro 2012. While known for their short passing game, Spain has a defense that has played a huge role in their Euro 2008 and World Cup 2010 victories. Can Sergio Ramos, the Val Kilmer of soccer, lead a defense that wins a historic Euro, World Cup, Euro triple crown?

What do you think?

Please leave us a comment. Thanks for reading.

Who would England, Spain and Germany be if they were NBA teams?

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The Power Rank predictions for Euro 2012 after the group stage
For most Americans, Euro 2012 is the reason the sports bar across the street keeps erupting during the middle of the day. The tourney has not become a mainstream event in America. Sports Illustrated has yet to mention a word about it in their magazine, opting instead to run a story about new United States men’s national team coach Jurgen Klinsmann.

But European Football Championships (that’s soccer) is one of the most exciting, competitive tourneys in the world. To make it more accessible for an American audience, we compared a few top teams to NBA teams. Really, this is an unsubtle attempt to convince our readers that we actually watch the games instead of just crunch numbers. While you can always see our win probabilities in this interactive bracket, we’ll attempt to pin a personality on three top team that have made the final 8 in Europe. You tell us how we do in the comments.

Ready?

England is the 2011 Memphis Grizzlies

England uses their size and physicality on the pitch. Many of their goals come from long passes into the box, such as Andy Carroll’s header off a Stephen Gerrard cross against Ukraine. Their back line features imposing players like John Terry, Joleon Lescott and Glen Johnson. They’re happy knock opponents off the ball, like Lescott did before his goal against France.

The NBA equivalent is the Memphis Grizzlies, a team build around physical post players Marc Gasol and Zach Randolph. These big guys are surrounded by athletes like Rudy Gay and O.J. Mayo. Sure, these are fine NBA players, but no one is drafting these guys for their dribbling or shooting skills.

We picked the 2010-2011 version of the Grizzlies because they knocked off San Antonio in the first round of the playoffs. This England team has the same potential to beat Italy in the quarterfinals. In fact, our algorithms give them a 49.2% chance of advancing. But just like Memphis got stoned in the next round against Oklahoma City, England’s journey will most likely end in the semi finals against Germany. England is a fine team, and our rankings place them at 7th in the world. They just live on a continent with Spain and Germany. Anything can happen though, and our methods give them a 10% chance to win Euro 2012.

Spain is the 2012 San Antonio Spurs

Spain plays a short passing known as tiki-taka. It’s a mischievious little game of keep away. When the Spanish artists play to their full potential, it’s one of the most beautiful thing in all of sports.

There is really no basketball equivalent. The closest comparison is this year’s San Antonio Spurs. Tim Duncan’s team was a passing machine, always swinging the ball around the court to find the open shot. This artistry led to a 39.3% shooting percentage from three point range.

Unfortunately for Spain, the comparison runs a bit further. Both San Antonio and Spain have players on the down side of their prime. On the Spurs, Tim Duncan and Manu Ginobili are 36 and 35 respectively. They couldn’t quite get over the hump against a young Oklahoma City team in this year’s playoffs. Spain’s midfield duo of Xavi and Andres Iniesta are 32 and 28 respectively. Their club team Barcelona could not reach the same play as in previous years. While The Power Rank gives Spain a 28.7% of winning Euro 2012, it reasonable to shave a few percentage off in favor another, younger team…

Germany is the Los Angeles Lakers of the early 80’s

I understand this is a hard comparison to stomach at first glance. The stoic Germans are like the flashy Lakers in the Magic Johnson days?

It’s about the style of play. The Germans are fearsome on the counter attack, the soccer equivalent of the fast break. It seemed almost inevitable they would score a winning goal against Denmark when the Danes were pushing hard for a goal. They have scored 2.69 goals per match in meaningful competitions since the start of qualifying for the last World Cup. While they haven’t scored more than 2 goals in any Euro 2012 match, they did have 4 goals outbursts against England and Argentina in the 2010 World Cup.

Now, this 2.69 goal average is inflated by 15 goals in 4 matches against Azerbaijan. However, our algorithms allow us to adjust for strength of schedule. The Germans have a 2.27 offensive rating, the best in the world. This means they would score 2.27 goals against an average international team.

We compare the Germans with the Lakers of the early 80’s because of their youth. Midfielders Mesut Ozil and Thomas Muller are 23 and 22 respectively. Even at this young age, this duo has already played together in a World Cup and European Championships. The Germans are improving as a unit, while Spain might be past its prime. The Power Rank gives the Germans a 25.9% of winning the tourney. From watching the Germans play, I think they should inherit a few percentage points from the aging Spain team.

What do you think?

We would love to hear other comparisons for England, Spain, Germany or any other European teams. Please leave us a comment.

Thanks for reading.

How did Spain’s odds of winning Euro 2012 change after their first group match?

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Spain didn’t look quite right.

Too many long balls over the top. Too many shots from outside the box. Not enough crisp passing between players forming triangles all over the field.

Did Italy’s defense take Spain out of their game? Probably not, as our algorithm ranks Italy’s defense 25th in the world. This isn’t the type of ranking one expects for a country famous for their catenaccio system.

Maybe it’s just Spain’s first game this tourney. Or maybe this core group of players is past its prime. We’ll find out in their next match against Ireland.

Spain’s odds to win Euro 2012 dropped from 22.6% to 21.5%. This is because Croatia beat Ireland today, putting them in control of this group with Italy and Spain. Croatia’s increased chance of making out of the group stage dropped Spain’s odds of advancing from 83% to 80%.

For our most updated win probabilities, click here to see our interactive bracket.

Thanks for reading.

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.