In this case, it is! The GP is using a uniform prior assigning "equally good chance" to either outcome (good or bad). http://en.wikipedia.org/wiki/Prior_probabi

In this case, it is! The GP is using a uniform prior assigning "equally good chance" to either outcome (good or bad). http://en.wikipedia.org/wiki/Prior_probability http://en.wikipedia.org/wiki/Prior_probability Of course stopping there seems to be silly since I'm sure more informed people have evidence that can shift that probability one way or the other.