The climax of the 2014 world cup is upon us, with the final games being played, and the outcome of the competition to be decided. One of the reasons why Brazil was one of the favourites going into the world cup was because they were going to be ‘at home’ for all of their games. But how much of an advantage was this really?
When we looked at all world cup competitions since 1930, it shows that 6 of the 20 World Cup competitions have been won by the hosts. Bearing in mind that on 5 other occasions the hosts had no realistic chance of winning themselves, this looks like quite a strong outcome. However the countries in question could have been favourites anyway. So more investigation is required.
Across many sports the impact of home side advantage is recognised  – it manifests itself in important games being played at neutral location, or having 2 legs one ‘home’, one ‘away’ to try to minimise any effect. The reasons cited are many and various (see Wikipedia article). When it comes to the 2014 Football World Cup, the effects of the weather and altitude appear to be the ones influencing player performance the most.
The strength of this effect for could be one reason why it is true that up to 2010, no team from outside of South America has ever won the title when the world cup was hosted in a South American country. It is interesting to note that with Germany being highly fancied to win the 2014 final in Brazil at the time of writing, this record could be broken.
 World Cup Winning Continent vs. Hosting Continent
Figure 1: World Cup Winning Continent vs. Hosting Continent

For the host nation does playing all your games ‘at home’ result in you progressing further than your FIFA world ranking at the start of the competition suggest?
As the host gets automatic entry into the competition this does result in teams of very variable abilities taking part, and not needing to qualify means that teams outside the top 32 getting into the tournament. This is true of non-hosts as well. The qualification phase for each world cup also results in teams progressing who are not in the top 32 and vice versa. As well as this the pools for early rounds and the consequential route to the later rounds also has an impact on whether the best teams progress. Notwithstanding all of the above, a quick analysis of all of the World Cup results from 1990-2014, where FIFA rankings are readily available, does show some interesting points.
Teams that are low in the FIFA rankings tend to over-perform when playing as host. Between 1994 and 2006, the host teams all appeared to benefit from ‘home advantage’. The star performer is France, who were ranked 18 in 2002, but subsequently went on to win, with Germany coming from a ranking of 19 to finish 3rd in 2006. The other impressive result was from South Korea, who came from a ranking of 40, and went on to come 4th.
What about hosts who are fairly well ranked going into the finals? Well Italy in 1990 was in this situation. They were favourites, so perhaps this is due to the pressure of national expectations. Although ranked number 1 they only came 3rd. Brazil in 2014 was ranked 3, so coming 3rd or 4th is pretty much in line with expectation. It’s a lot harder to do better than your ranking when it is already high.
  FIFA Ranking vs. Final Position in Competition
Figure 2 : FIFA Ranking vs. Final Position in Competition

The analysis shows that over the last 7 World Cups only one country (Italy) did worse that ranking would expect. However they were ranked number 1 at the start, so it was difficult to do better than that! So there does seem to be a pattern that World Cup hosts do on average benefit from home advantage, but it does help to start the competition with a low ranking. So looking forward to the next world cup, Russia are currently ranked at 19 in the world, and unlikely to rise too much above that – so from our analysis, we expect them to make it through to the quarter finals come the next world cup.