Before getting to the results, let me explain the methodology used to evaluate the predictions. I identified the final standings at the end of the 2010-2011 season as the baseline evaluation of skill. Skill refers to the ability to out-perform a naive baseline. The choice of naive baseline is arbitrary. Specifically, for each place in the table, I take the difference between that place and a predicted place and square it. So if you predicted Bayern in 4th and they are in 1st, then the difference is 3, and squared is 9. I then add up the squared differences for all 18 places, and then take the square root of that sum. That gives a measure of the total error in the prediction.
Here are the results at mid-season:
Four of the six participants show skill, if last year's table is used as the naive baseline, but only two show skill if Der Spiegel's pre-season prediction is used as the naive baseline.
There is also a preliminary conclusion that suggests being located in Colorado is correlated with extreme skill, but I think we'll need more data to confirm the association! ;-)
Stay tuned, I'll provided the skill table for the Premier League contest next week!