Let X be a random variable taking values in the positive integers, with probability mass function of the form:
pX (k) = 2/3^(−k)
Does E(X) and V (X) exist for this pmf? and how should I calculate them? or why they are not exist?
Let X be a random variable taking values in the positive integers, with probability mass function of the form:
pX (k) = 2/3^(−k)
Does E(X) and V (X) exist for this pmf? and how should I calculate them? or why they are not exist?