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Much is made following the World Cup draw every four years over which group is the “group of death.”  This is generally considered to be a really difficult group that is tough to advance from, although there is no true definition (more on that below).

First, for readers not familiar with World Cup groups, a brief explanation of how teams are “grouped” in the World Cup is in order.  Thirty-two teams qualify to compete, and they are placed into eight different groups labeled A-H, with each having a predetermined “top” team.  In the group stage of the World Cup, each team plays the other three teams in their group, and the top two teams move into a standard bracketed tournament. The bottom two teams watch the rest of the tournament on TV, like the rest of us.

So how do you decide which group is the Group of Death?

There is no formal definition, so let’s look at a few possibilities and see what we can learn by analyzing some data. To do so, I’m going to use the team ratings found at eloratings.net although other rating systems exist.

Highest Average Rating

One quick method to look for a Group of Death would be to see which group has the highest average rating among their four teams…this group would be the most difficult, after all. 

Here are the ratings of every team in every group, with the group average plotted as well:

Highest Average Rating

Group B (Spain, Netherlands, Chile, Australia) obviously has the highest average, followed by Group G (Germany, Portugal, USA, Ghana).  So based on this method, Group B is the most difficult and the Group of Death for 2014.

Variation

But take a closer look at Group B, and you’ll notice how widely spread the teams are…the top team (Spain) is significantly better than average, and the bottom team (Australia) probably has little hope of qualifying.  If the top team is likely to qualify and the bottom team likely is not, then the group really can’t be that competitive and considering it a “Group of Death” seems a bit dramatic.

What if instead we considered the Group of Death to be one in which the teams are closely rated, which makes the group highly competitive – even the best team is far from certain to advance past the group stage. 

So instead, let’s look at the standard deviation of the ratings within each group:

Variation

Now we see that Group C (Colombia, Greece, Ivory Coast, Japan) is actually highly competitive and may qualify as the Group of Death.

2nd to 3rd Gap

It could be, however, that the entire group doesn’t need to be highly competitive in order to be a “Group of Death.”  The Group of Death designation could simply mean that it is not clear which teams are most likely to advance. Having one really weak team in your group would raise the variation, but if the other three are very competitive with one another then your group could easily get the title.

First, let’s take a look at the rating difference between the second- and third-highest rated teams in each group:

2-3 Gap

By this measure, Groups A, D, and E look to be very competitive for making it to the second spot to advance.

Top 2 Versus Bottom 2

Another measure of competitiveness for advancing would be to look at the average ratings of the top two teams in each group versus the bottom two, as a large difference indicates that it is unlikely there will be surprises within the group:

Top 2 vs Bottom 2

By this measure, Groups C, D, and E appear highly competitive and the bottom teams can easily surprise and move on, making it a Group of Death for teams rated at the top.

Best Team Left Out

As a final measure, I’ll look at the highest-rated team left out after the group stage. The third-highest rated team in any group has the lowest possible rating of the best team left out.  So the better that team is, the better the group fits the Group of Death mold: a very good team will not move on because of the difficulty of the group.

Here is the rating of the third-best team in each group:

3rd-best Rating

Groups B and D each have really good teams that are only the third-best in the group, meaning at least one really good team will not advance from these groups. In fact, the third-best teams in these groups rank 10th (Chile) and 11th (Italy) in the world!  By comparison, the third-best team in Group H is ranked 42nd (South Korea) in the world.

So Which Group Is the Group of Death?

The analysis here definitely illustrates one thing: without any agreed-upon definition of a “Group of Death,” it is very difficult to clearly distinguish which group deserves the designation.

Sometimes there is no single metric that best measures what you’re trying to analyze, and looking at a few different measure helps clarify things. Although not the most extreme on many of these methods, I would look at Groups B and G as the most likely candidates for Group of Death in 2014 World Cup, as each tended to rate well on most measures. 

That is, unless there isn’t really such a thing as a Group of Death…

 

Comments for Is There a World Cup "Group of Death"?

Name: Athar Siddiqui
Time: Wednesday, January 22, 2014

i loved this article - I love football too so was following along from that point of view also. I never even thought of the varying possibilities. But these did make sense to me! At the end of the day, the pundits will call the Group of death, that group that has the most of the highest ranking teams as considered by the pundits. The stats should back that up, assuming the rating numbers are consistent with the pundits views. And one pundit of course may have different views so in the end its back down to gut feel! Thanks for the thought-provoking article though!
Athar

Name: Kent V
Time: Wednesday, January 22, 2014

Is there a reason there are only 3 apparent data points (teams) in some groups on the first graph? Or does one point fall on the average snake line?

Name: Doug J
Time: Wednesday, January 22, 2014

This was and excellent read. The first thing I did after the draw was look up the ELO and FIFA rankings and do some of basic analysis. I like to use the ELO rankings because they seem to align more with the general thoughts on the teams and less about the political bias in the ranking system. I like the different perspective of how to determine what makes it the Group of Death. Most pundits look at the whole group and not who will finish in the top two which is what really matters. Now Joel Smith, you need to determine how the "Group of Death" played out in previous World Cups!

Name: Mncedisi Jack
Time: Thursday, January 23, 2014

Indeed group B and group G are the group of Deaths. If I had to choose 1, I would definitely say group G, since I know that even though Austtralia might have a rating more than Ghana, there is no chance for Australia beating Ghana at any stage of football. In conclussion,the best metric is Highest avarage method, though I dont like take conclussions on avarages.

Name: Joel
Time: Thursday, January 23, 2014

Thanks for reading everyone and for the comments!

Kent - in Group C, the fourth point is directly under the mean symbol and a little hidden. In the cases of groups A, E, and F there are in each case two teams that fully or nearly overlap as the rankings are so close together.

Doug - I definitely chose the ELO rankings for a reason. As with any sport there is no "right" system but statistical rankings systems have shown to consistently perform better than systems that use arbitrary point values like the FIFA rankings. As for examining the past, sounds like you'd like to be a guest blogger!

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