In a Poisson distribution, the probabilities for x = 1 and x = 2 are equal when the mean u is set to 1. The calculations show that the probabilities for p(0) and p(1) result in both being e^(-1), approximately 0.3679.
A Poisson distribution is such that the probability is the same for .pdf
1. A Poisson distribution is such that the probability is the same for X = 1 and X = 2. What is this
probability?
Solution
Note that for a Poisson distribution,
P(x) = u^x e^(-u)/x!
Thus,
P(0) = e(-u)
P(1) = u (e^-u)
Thus,
u(e^-u) = e^(-u)
e^(-u) (1-u) = 0
Thus,
u = 1
Thus,
P(0) = P(1) = e^(-1) = 0.367879441 [ANSWER]