Monday, August 31, 2009

World Cup Qualifying - CONMEBOL

How It Works

All 10 teams play under the league format. Each team plays every other team twice, once in each country. The top four teams automatically advance to the finals in South Africa, the fifth-place team has to win a playoff against the fourth-place team from CONCACAF.

Where the Group Is Now

Brazil are sitting pretty at the top, 7 points clear of the playoff spot. Chile are doing quite well just one point behind. Paraguay are also in great shape, four points clear of fifth. Argentina do not look as good as usual and sit just two points ahead of fifth-place Ecuador going into their match with Brazil this weekend. At the bottom, Bolivia and Peru are effectively out of it while Colombia and Venezuela all have a shot but are running out of time with only four matches to go. Uruguay should challenge Ecuador for that fifth spot and could even catch Argentina.

Peru and Bolivia have been significantly worse this qualifying campaign than the bottom teams have historically been - with the exception of Venezuela before France '98 with just 3 points. Four years ago at this point both were the bottom two teams as they are now, but in the other order. Bolivia had 13 points and Peru 14. As a result, it looks like more points will be required this year to make the finals. Four years ago at this point, there was a 3-way tie for fifth. Colombia, Chile and Uruguay all had 17 points. Right now fifth is a full 3 points higher. Argentina haven't looked nearly as good as usual and Chile have given us a much better showing than they historically have. Otherwise there's nothing too strange going on.

Poisson Predictions

I put the qualifying results into the Poisson model. I also ran a version where I included the matches from Copa America, which took place in 2007. It didn't change things much. Putting those results in made Ecuador look a bit better and Uruguay a bit worse. In qualification chances, it bumped Ecuador up about 7%, decreased Uruguay 6.2% and also reduced Colombia's chances 0.7%. Other teams changed only slightly.

Here is the chart with just the qualification results:

The format is similar to what I used in the CONCACAF article. The first numbered column gives the percentage chance of finishing in the top 4, which automatically qualifies you for South Africa 2010. The second column gives the chance of finishing in fifth place, which puts you in a playoff against the 4th-best team from CONCACAF. The out column gives the chance of finishing 6th or worse - this eliminates you from the competition. The last column gives the chance of qualification if a potential playoff with the CONCACAF team would be a 50/50 proposition. As I said in the earlier article, I think this underestimates the chances a bit because whichever team finishes fifth here is probably a small favorite over the CONCACAF team finishing fourth.

As you can see, Brazil, Chile and Paraguay are effectively in and Bolivia and Peru are effectively out. In 100,000 simulations, Brazil finished in 5th 8 times and the other 99,992 times they were in the top four. I'd say they're pretty safe. Similarly, Peru didn't finish in the top 5 for even one of the 100,000 simulations.

Things are much more interesting in the middle. Argentina are still favored to get in, but they're certainly no lock. Of the four other contenders, Uruguay rates the best. This is likely due to their schedule - they play at Peru this weekend and face rivals Colombia and Argentina at home. Their toughest test is a trip to Ecuador. Meanwhile, Argentina have Brazil left on their schedule and Ecuador wrap things up with a trip to Chile. That likely means that the model will underrate Ecuador's chances because most likely Chile will have nothing to play for in that match and a win for Ecuador wouldn't be unlikely in the event that they need one, even though they are the worse team and playing away.

Saturday's Matches

Argentina - Brazil

Importance for Argentina:
A win would be a huge boost to their chances, and even getting a single point would help. With a win, Argentina go from the 53% chance they currently have to automatically qualify to 78%. Overall their chances go up to 88% to make it to South Africa if you assume they'd be 50/50 but it's probably more like 93% since they'd be a solid favorite in a playoff. So a win gives them about a 10% better chance of making it. A draw leaves their numbers pretty much unchanged. A loss would be bad though, and the likelihood that they finish in the top 4 would drop 14 percentage points to 39%. They would lose about 10% for their overall qualification chances.

Importance for Brazil:
Effectively none. They're in either way.

Colombia - Ecuador

Importance for Colombia:
Colombia's chances are quite slim either way. A win makes them about twice as likely to finish in fifth, which about doubles their chances of qualifying to a little over 4%. If they lose they are effectively out. A draw roughly cuts their chances in half.

Importance for Ecuador:
This match for Ecuador is pretty important. A loss reduces their chances of finishing in the top 4 by about 5.5% and their overall chances by about 10%. A draw keeps them pretty much where they are, they only lose a couple percentage points. A win would be a huge boost. If they win then their chances of a top 4 finish roughly triple to about 21%. Overall they would be about twice as likely to qualify going from 19% to 38%.

Peru - Uruguay

Importance for Peru:
None. They're out.

Importance for Uruguay:
This is close to a must-win for Uruguay. With a win they are in pretty good shape - probably in fifth place, possibly just a point behind Argentina in fourth. Their chances of finishing in the top 4 go up 10 points to 49% and they'd become about 2:1 favorites overall to qualify with a win. A draw would reduce their chances to 27% for the top 4 and about 44% overall. A loss would be devastating and they would drop to just a 15% shot at going automatically and 32% overall.

Paraguay - Bolivia
Chile - Venezuela

Both of these matches feature a team that is virtually certain to make it and one that is just as likely to finish outside the top 5. Chile and Paraguay would be pretty much unaffected even by a loss. If Venezuela pull the upset then they would go from practically no shot to having a small chance - about 8%.

1 comment:

  1. Nice work Jared.

    Really looking forward to Brazil and Argentina and if Maradona the manager has made any progress with this (extremely talented) team.

    "Bjørn" on 2+2