An alarm company reports that the number of alarms sent to their monitoring center from customers owning their system follow a Poisson distribution with $\lambda = 4.7$ alarms per year. Identify the mean and standard deviation for this distribution.
A) mean $= 2.17$, standard Deviation $= 4.7$
B) mean $= 4.7$, standard Deviation $= 4.7$
C) mean $= 2.17$, standard Deviation $= 2.17$
D) mean $= 4.7$, standard Deviation $= 2.17$

Question

Quizplus · Accepted Answer

For a Poisson distribution, the mean is equal to $\lambda$, which is 4.7. The standard deviation is the square root of $\lambda$, which is approximately 2.17.

An Alarm Company Reports That the Number of Alarms Sent λ=4.7\lambda = 4.7λ=4.7

An Alarm Company Reports That the Number of Alarms Sent $\lambda = 4.7$