Assume that times of failures of a computer network can be m

Assume that times of failures of a computer network can be modeled using a Poisson process with mean 10 failures per year. What is the standard deviation of the waiting time to the first failure? (Time is measured as the part of a year, for example 0.500 means half a year).

(a) 0.222 (b) 0.1 (c) 0.333 (d) 0.471 (e) none of the preceding

Solution

the standard deviation of a poisson distribution is srqt var

and the variance of a poisson distribution is the mean

Var = 10

SD = srqt (10) = 3.16