3 - poisson distribution Flashcards
1
Q
conditions
A
events occur at random
independent
average must be constant
2
Q
P(X = x)
A
e^λ λ^x / x!
3
Q
E(X)
A
λ
4
Q
Var(X)
A
λ
5
Q
scalability
A
it’s scalable if in 10 mins you see 3 cars in 20 mins you’ll see 6 on average
6
Q
if X~Po(λ) and Y~Po(u)
and Z = X+ Y
A
Z~Po(λ + u)
