Fill in the blank. The standard deviation of the Poisson distribution is calculated using The standard deviation of the Poisson distribution is calculated using

Step 1 ：The standard deviation of a Poisson distribution is calculated using the square root of the mean (λ). This is because for a Poisson distribution, both the mean and the variance are equal to λ. The standard deviation is the square root of the variance, so it is also the square root of λ.

Step 2 ：Final Answer: The standard deviation of the Poisson distribution is calculated using the square root of the mean (λ).