January 20, 2009 | MSNBC.com
In a story about the Hollywood Stock Exchange's Oscar prediction market, it's noted that the Iowa Electronic Markets offered markets to predict box-office figures for some time now, and marketing professor Tom Gruca said neither the IEM nor the HSX has been very good at the game. The average percentage error for the IEM's forecasts is 38 percent, while the equivalent predictions from the HSX have been off by 31 percent on average. "Forecasting movies is a very difficult problem," Gruca said. "There's an enormous amount of data out there for traders to aggregate, but how do you put it all together? Nobody's learned yet how to distill all that information into a consistently accurate forecast."