Peter Bromberg's UnBlog

“The generation of random numbers is too important to be left to chance.” — Robert R. Coveyou Often when confronted with difficult decisions, I resort to a simple coin toss to "get objective". But, flipping a coin may not be the fairest way to settle disputes. About 13 years ago, statistician Persi Diaconis started to wonder if the outcome of a coin flip really is just a matter of chance. He had Harvard University engineers build him a mechanical coin flipper. Diaconis, now at Stanford University, found that if a coin is launched exactly the same way, it lands exactly the same way. The randomness in a coin toss, it appears, is introduced by us sloppy humans. Each human-generated flip has a different height and speed, and is caught at a different angle, giving different outcomes. But using high speed cameras and equations, Diaconis and colleagues have now found that even though humans are largely unpredictable coin flippers, there's still a bias built in: If a coin star...