Tuesday, September 08, 2009

Ghana doesn't feature in the FIFA 30 but are in the ELOs!

Ghana does not feature in the Fifa rankings of September despite being the first in Africa to have qualified for the 2010 event. And that brings (familiar) bashing of the Fifa rankings.

The Fifa rankings have come in for critique for years and years. Especially as the people in Zurich seem to put undeserving teams in positions of prestige all the time.

Take, for instance, putting the USA in fifth position around the time of Germany 2006 and you know what i mean.

So what's the alternative? Answer: Elo ratings.

This was adapted from Dr. Elo’s world chess rating system by footy fan Bob Runyan. How do the two differ? Basically the FIFA system works like a big league table of the last four year’s results, but with points weighted by the type of game (eg World Cup final more valuable than a friendly), the opposition, confederation and time past since the game. My colleague at WCB, Laurie, furnished us with an excellent explanation here (seriously, go read that if you want to understand the FIFA system.)

The Elo system works a little - but not dramatically - differently. As with FIFA’s it’s a giant league table, but using data from (and I quote) “international football 1872 - present”. The system takes into account the type of game (World Cup, friendly, etc) but also the score as well as the result (ie how many goal did a team win by) and also the win expectancy (ie was the team expected to win, and by how many goals.)

A full explanation of the Elo football system can be found here.

In the end (to numerical simpletons like myself) it’s all just numbers and formulas. Who can say whether FIFA’s P = M x I x T x C x 100 is any better than Elo’s Rn = Ro + KG(W − We) ? The proof is really in the pudding.

And in this case let's see what Fifa's first 30 rankings for September says...and what the Elo's say too.

FIFA:


Elo:


So what do you think?