As you probably know, the James Randi educational foundation offers 1 000 000$ for "any psychic, supernatural, or paranormal ability under satisfactory observation".
But sometimes such claimed ability is said to be "not working all the time". Like in, say, dowsing or astrology -- it just increases the probability (compared to random guessing) of getting something right.
Still, such claims can be tested using statistical significance testing techniques. The "confidence" in the results of such statistical tests is called "the statistical significance" -- a probability that the claimant does not have any supernatural abilities and just guessed the right answers.
The probability that one have to beat in the "one million challenge" seems to be equal to 1 in 100000.
But some opponents of James Randi say that in order to start using the supernatural effects in practice ("for the benefit of Mankind" so to say) such significance is too high. "Some researchers", they say, "are using significances of 5%. And still making progress."
I'm working in particle physics, and in my field in order to establish a discovery we require "5 sigma", which amounts to significance of about 1 in two million. So, for me Randi's requirement is too soft.
But what about other fields? Like medicine or biology? Or even sociology and psychology? Is there any overview of the significances for these disciplines and what is considered "a discovery" for them?