The probability distribution or, simply the distribution of a discrete random variable X is a list of the distinct numerical values of Xalong with their associated probabilities. Often, a formula can be used in place of a detailed list.

Form of a Discrete Probability Distribution

The probability distribution of a discrete random variable X is described as the function f(xi)=P[X=xi] which gives the probability for each value and satisfies:

1.
, for each value xi of X.
2.