THE POWER RANK

Win probabilities for the 2015 Gold Cup

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Screen Shot 2015-07-06 at 11.37.32 AMCan the United States win the 2015 Gold Cup?

Winning the Gold Cup means more than than just bragging rights over rival Mexico. With the win, the United States qualifies for the Confederations Cup in 2017, a key tune up tournament for the World Cup in 2018.

If another team wins the Gold Cup, they play a one game playoff against the United States, winner of the 2013 Gold Cup. The winner of this playoff represents North America at the Confederations Cup.

To determine win probabilities for the Gold Cup, I combined three different estimates into an ensemble prediction. Two came from my own calculations that rank international teams on offense and defense (see the bottom of this article), and a third came from the markets.

goldcup2015

The Gold Cup usually comes down to the United States and Mexico, but Costa Rica has emerged as a solid third team that made the final 16 of the World Cup last summer.

Let’s look at these three top contenders. The offense and defense rankings come from The Power Rank algorithm and use international matches since January 1st, 2011.

United States

12th offense, 27th defense

The United States looked fantastic in beating Germany in a friendly last month, and they also beat the Netherlands in another friendly. Both matches took place on European soil.

They need to play well at the start of the Gold Cup as their group has Honduras and Panama, two top 50 teams in my world soccer/football rankings. Meanwhile, Mexico has the dregs of CONCACAF (Guatemala, Trinidad and Tobago, Cuba, all ranked lower than 80th) in their group.

Coach Jurgen Klinsmann left central defender Matt Besler, who started every game of last year’s World Cup, off the Gold Cup roster. John Brooks will most likely start, and let’s hope they can improve a defense that has ranked 27th in the world over the last 4 years.

Mexico

11th offense, 9th defense

By the numbers, Mexico has a slight edge on the United States in my rankings. They don’t have the largest win probability though since the United States will enjoy home field advantage.

I’m not 100% certain the United States should get the full .59 goals for home field. If the United States and Mexico meet in Philadelphia for the final, there will be plenty of Mexican fans wearing green in attendance.

In my ensemble calculations, the market predictions most likely account for the semi-neutral type final in Philadelphia. They gave United States a 38% win probability with Mexico at 36%. The gap was bigger in my two calculations.

For Mexico, striker Javier “Chicharito” Hernandez broke his collar bone and will miss the Gold Cup. He scored 9 goals in 33 matches for Real Madrid last season.

Costa Rica

40th offense, 10th defense

Costa Rica had an amazing World Cup last summer. In winning their group, they sent Italy and England home before the knock out stage. Then they beat Greece to advance to the Round of 16.

Costa Rica relies on its defense, which is ranked 10th in the world over the last 4 seasons. They face a road game against Canada in Toronto in the group stage, but they should win their group before most likely playing the United States in the semi-final.

List of win probabilities for the 2015 Gold Cup

1. United States, 39.1%.
2. Mexico, 33.6%.
3. Costa Rica, 11.7%.
4. Panama, 4.7%.
5. Honduras, 4.7%.
6. Jamaica, 2.3%.
7. Guatemala, 1.8%.
8. Canada, 1.4%.
9. El Salvador, 0.9%.
10. Trinidad and Tobago, 0.7%.
11. Haiti, 0.1%.
12. Cuba, 0.1%.

Television Interview on Ronan Farrow Daily

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me_ronan_mauriceRonan Farrow interviewed me and Maurice Edu about the World Cup on his MSNBC show yesterday.

I was pumped to meet both the host and one of the best soccer players in the United States. However, there’s not much contact when they film you from a remote location.

To do the interview, I went to a studio in my home town of Ann Arbor. A nice guy Tony set everything up.

From a remote location, I could only hear Ronan and Maurice in my earpiece. I couldn’t see them or what appeared on television.

Still, it was fun. We talked World Cup, the United States’ chances against Belgium in the Round of 16 and how numbers affect the psychology of players.

To view the interview, click here. If you’re viewing on Tuesday, July 1, it should be the main video under “Betting on the World Cup.” Otherwise, you might have to scroll through the videos on the right.

Aggregating the results of many World Cup prediction models

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wc2014_winprob_ensemble10Who will win the 2014 World Cup?

There is no shortage of quants making their own prediction. These range from my own at The Power Rank to the financial types at Goldman Sachs.

As much as I’d like to think my model is the best, research has shown that combining the results of many models often gives a better prediction. If you want to sound smart about combining predictions, you say the words ensemble learning.

The visual shows the average win probabilities for 10 different World Cup models, which are described at the bottom of this post. This list gives the full results.

1. Brazil, 28.64.
2. Spain, 12.62.
3. Argentina, 11.49.
4. Germany, 10.75.
5. Colombia, 3.73.
6. France, 3.72.
7. Portugal, 3.47.
8. Netherlands, 3.41.
9. Uruguay, 2.89.
10. England, 2.85.
11. Belgium, 2.34.
12. Chile, 1.87.
13. Italy, 1.84.
14. Ecuador, 1.43.
15. Russia, 1.13.
16. Ivory Coast, 1.05.
17. Mexico, 1.02.
18. United States, 0.82.
19. Switzerland, 0.78.
20. Bosnia-Herzegovina, 0.67.
21. Greece, 0.64.
22. Croatia, 0.58.
23. Japan, 0.45.
24. Nigeria, 0.44.
25. Ghana, 0.40.
26. South Korea, 0.22.
27. Iran, 0.17.
28. Algeria, 0.16.
29. Cameroon, 0.11.
30. Honduras, 0.11.
31. Costa Rica, 0.09.
32. Australia, 0.08.

The aggregated predictions neatly split up the 32 team field into 3 classes.

Brazil

First, Brazil has the highest win probability at 28.6%. This results from their status as a traditional power as well as home country advantage in this World Cup.

Research has shown that referee bias plays a large role in home advantage. Yesterday’s opening game between Brazil and Croatia was the perfect example.

Despite playing poorly overall, Brazil was awarded a penalty kick on a terrible call in the second half. Neymar converted, giving Brazil a 2-1 lead.

Then the referee missed a foul on Brazil deep in Croatia’s end of the field. As a result, Oscar scored a beautiful goal to finish off a 3-1 win.

The other three elite teams

The second class of teams consists of Spain, Argentina and Germany, teams with greater than 10% win probability each. Should Brazil stumble, one of these traditional powers should lift the trophy.

Spain won the last World Cup with their mesmerizing short passing game and stout defense. Despite the advanced age of their stars, they have a 12.6% chance of winning the World Cup.

Argentina is probably the weakest of these three teams. However, some of the models included a home continent advantage for Argentina. This puts them ahead of Germany with a 11.5% chance to win.

Germany is a dynamic young team with a potent offense. The Power Rank thinks they’re the best offensive team in the world by a significant margin. However, their defense can let them down, as it did against Italy in Euro 2012.

Most models and pundits consider Brazil, Spain, Argentina and Germany the favorites to win the World Cup.

Randomness in soccer competitions

The remaining 28 teams make up the third class of teams. There’s 36.5% chance that one of these teams wins the World Cup, the event that interests me most.

This type of “upset” has not happened recently at the World Cup. The last 5 World Cup champions are Spain, Italy, Brazil, France and (West) Germany, all traditional football powers.

However, the World Cup offers a small sample size of matches.

The group stage has three games. Have you ever looked the table of your favorite league after 3 games? The best do not necessarily rise to the top that early in the season.

After the group stage, the World Cup enters the knock out stage with 16 teams. The top teams do not always survive a single elimination tourney.

Manchester City, the Premier League champions this season, did not make the finals of the FA Cup. Hull City, 16th in the Premier League table, did.

Americans know the randomness of single elimination tourneys well from the NCAA men’s basketball tournament. This season, top teams like Arizona, Louisville and Florida failed to win the title. An unheralded Connecticut team, angry over the 1.5% win probability from The Power Rank, won the tourney.

While the World Cup hasn’t had an upset winner lately, the same is not true for the European Championships.

In 2004, Greece qualified for their first championships in 24 years. They won Euro 2004.

In 1992, Denmark only qualified when people started shooting each other in Yugoslavia. They won the competition.

Will 2014 be the year that randomness descends on the World Cup? Stay tuned.

Models used in the aggregate predictions

These 10 models were used.

  • The Power Rank, using a 12 year window of matches. A description of the simulation methodology is here, while an explanation of using such a long window of games is here.
  • The Power Rank, with a 4 year window of matches, weighted by importance of the match. These rankings were quite different from the 12 year rankings above. Germany was the top team instead of Brazil. A big reason was their 4-0 win over Argentina, a 2010 World Cup match that got 4 times the weight of a friendly in the rankings.
  • Betting markets at Bovada.
  • Infostrada, emailed to me from Simon Gleave.
  • Michael Caley at SB Nation used a least squares method that considered shots in addition to goals.
  • Numberfire.
  • Goldman Sachs. I would have never used their results had they continued to use the FIFA rankings like they did in 2010. However, they transitioned to Elo ratings, which are more accurate for international soccer.
  • David Dormagen. He aggregates a number of different rankings. Not a fan of how he calculates ties, but…
  • Roger Kaufman.
  • Bloomberg Sports, who do their own rankings.

Check out the interactive visual for the World Cup

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Screen shot 2014-06-09 at 10.17.53 PMThe World Cup starts today, and this interactive visual shows you all the important numbers.

It starts with international soccer/football rankings from The Power Rank. This method takes the scores in games and adjusts for strength of schedule. The Power Rank can not only rank teams but also offense and defense.

These rankings feed a simulator that plays the World Cup 10,000 times. By counting the number of times an event happens, like the United States finishes 2nd in Group G, we obtain the probabilities for certain events.

For more details on my methods, click here.

Data visualization

Unlike most sites, we don’t want you to go blind reading these numbers in a table. In collaboration with Andrew Phillips at Chartball, we created this interactive visual with World Cup probabilities.

Hover over a team name to see the odds that they advance through the stages of the competition. The group of circles closest to the team name corresponds to the probability of winning the group. The next closest circles correspond to second place.

For the round of 16, a team can enter this stage of the competition via two routes: winning the group and placing second in the group. Hence, each team has two probabilities for the round of 16. The gray lines show which circles correspond to which scenario.

Each team also has two probabilities for the quarter and semi-finals for the same reason.

Hover over the circles at any stage of the competition to see the corresponding team.

The visual will be updated each night after the games.

The nature of these probabilities

The rankings used for the visual consider the last 12 years of international play. Research by others has shown that these rankings are as accurate as rankings that consider the last 4 years of play.

However, these rankings tend to underestimate up and coming teams like Belgium, a team that suddenly has stars on major European club teams. While my rankings have them at 41st, they’re more likely a top 20 team.

The visual has Russia as the top team to win Group H at 42%. However, I’m probably underestimating Belgium’s chances at 24%.

World Cup 2014 win probabilities from The Power Rank

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wc2014_winprobWho will win the 2014 World Cup?

The visual shows the top contenders according to The Power Rank. This list gives the odds for all 32 teams.

1. Brazil, 35.9%.
2. Argentina, 10.0%.
3. Spain, 8.9%.
4. Germany, 7.4%.
5. Netherlands, 5.7%.
6. Portugal, 3.9%.
7. France, 3.4%.
8. England, 2.8%.
9. Uruguay, 2.5%.
10. Mexico, 2.5%.
11. Italy, 2.3%.
12. Ivory Coast, 2.0%.
13. Colombia, 1.5%.
14. Russia, 1.5%.
15. United States, 1.1%.
16. Chile, 1.0%.
17. Croatia, 0.9%.
18. Ecuador, 0.8%.
19. Nigeria, 0.8%.
20. Switzerland, 0.7%.
21. Greece, 0.6%.
22. Iran, 0.6%.
23. Japan, 0.6%.
24. Ghana, 0.6%.
25. Belgium, 0.4%.
26. Honduras, 0.3%.
27. South Korea, 0.3%.
28. Bosnia-Herzegovina, 0.3%.
29. Costa Rica, 0.3%.
30. Cameroon, 0.2%.
31. Australia, 0.2%.
32. Algeria, 0.1%.

For those interested in my methods, see the end of this post.

But first, some quick thoughts on a few teams.

Brazil

The host nation Brazil has the highest win probability at 36%.

Home advantage plays a big role in these large odds. On average, the home team scored about 0.56 goals more than the road team over the last 3 cycles of World Cup qualifying.

As discussed in the book Scorecasting, referee bias plays a big role in home advantage. In last year’s Confederation Cup final, Spain tried to execute their short passing game against the home nation Brazil. From my perspective, the referees let Brazil get away with fouls that stymied Spain’s attack. Brazil won 3-0.

But Brazil also plays some magnificent soccer as the top ranked team in The Power Rank. Their young star Neymar will dazzle you with his quick feet and skills.

Argentina

The other traditional soccer power from South America, ranked 3rd in The Power Rank, has the second highest win probability at 10%.

Argentina benefits from a weak group with Bosnia-Herzegovina, Iran and Nigeria. I like to call it Group of Eternal Life. They have a 85% chance to advance to the knock out stage.

Argentina might also benefit from a home continent advantage. It’s much easier for Argentina fans to travel to Brazil for the World Cup than nations from Europe. Enough fans in attendance could create a home advantage effect like Brazil will enjoy.

I did not include a home continent advantage in my model, so Argentina might have even better odds than 10%.

United States

Expectations are different for the United States. Surviving a tough group with Germany, Portugal and Ghana would be a huge achievement. My numbers give the Yanks a 38% to make the knock out stage.

Those are decent odds for the 20th ranked team in the world. I also looked at their ranking when including only games with Jurgen Klinsmann as coach. Despite all those goals they scored in last year’s Gold Cup, the United States only rises to 17th.

The road to winning the World Cup gets harder in the knock out stage. The United States has a 1.1% chance to win the World Cup, 15th best out of 32 nations.

However, Connecticut had a 1.5% chance to win the 2014 NCAA men’s basketball tourney by my numbers. They beat Kentucky to win an improbable title.

Better predictions

Here’s the truth: If you want the most accurate predictions about who will win the World Cup, you shouldn’t just look at my predictions.

One system is not enough. Research has shown that better predictions arise from aggregating many predictions. This was a key finding in a recent academic paper on using rankings to predicting football matches.

Yeah, it’s a blow to my massive ego. 🙂 But you deserve the best possible predictions for the 2014 World Cup.

I’m curating World Cup predictions from other sources. Next week, I’ll aggregate these predictions for my email list, since they’re my favorite people in the world.

If you want to see those results (and you really should if you’re in any kind of World Cup pool), sign up for my free email newsletter. It’s the best way to get updates on The Power Rank’s content.

Just enter your email address and click on “Sign up now.”








Methodology

Still reading? Thanks, you’re the best.

The World Cup win probabilities start with The Power Rank’s algorithm for ranking teams. It takes margin of victory in matches and adjusts for strength of schedule. With the wide disparity between countries in international soccer, this adjustment is critical for predicting the World Cup.

This algorithm can not only rank teams but also the offense and defense of each team. This allows me to estimate the goal rate for an offense against an opposing defense.

To predict the outcome of a match, I pick a Poisson random variable according to these goal rates per 90 minutes. This model says a team has the same rate of scoring a goal at any point in the match.

For example, teams score 1.34 goals per 90 minutes in international play. This implies that a team has a 1.4% chance to score a goal during any minute. For each minute, you could flip a coin that comes up heads 14 out of every 1000 flips. Repeating this flipping 90 times and counting the heads is the same as getting goals from a Poisson random variable.

To simulate the World Cup, I use this Poisson model for each match in the group stage. To see the predictions for all 48 matches, check out the predictions page.

This model gives not only the winner or loser of each match but also a score. The scores allow for the calculation of tie breakers, which consider goal differential and goals scored.

The same Poisson model applies in the knock out stage. If two teams are tied on goals after regulation, the model is applied again for extra time. I assume each team has a 50-50 chance to win penalty kicks.

The win probabilities arise from counting the number of times each team wins over 10,000 simulations.