ENTIRE OLYMPICS PREDETERMINED: New Scientist article on these economists who had a 96 percent success rate in Sydney in terms of predicting numbers of medals won. They use no information about the athletes themselves to make their predictions:

Their accuracy is uncanny, considering they have never taken any athlete's sporting prowess into account. Johnson and Ali base their predictions on little more than a country's GDP, political situation, and its population, latitude and climate. They created their predictions by investigating how these factors were related to past Olympic achievements. The aim was to analyse how economic and political conditions can affect a nation's sporting achievements.

As you might expect, they found that the probability of success is closely related to a nation's wealth. But there were also surprises in the data. Athletes from communist and single-party regimes excel at winning medals, Johnson says. Contrary to popular belief, these nations don't send disproportionately many athletes, but they consistently outperform other nations with the same economic and geographic attributes. The difference is, on average, 18 summer medals and 10 winter medals.

You can read the actual paper here.