Converting between nines and sigmas

1 · John Cook · June 20, 2019, 11:20 a.m.
Nines and sigmas are two ways to measure quality. You’ll hear something has four or five nines of reliability or that some failure is a five sigma event. What do these mean, and how do you convert between them? Definitions If a system has fives nines of availability, that means the probability of the system […]...