Discrete Random Variable

What is a Discrete Random Variable:

A discrete random variable is a random variable with a limited and countable set of possible values. These variables are usually used with a probability histogram to graph the possible outcomes of a repeating scenario with a limited number of outcomes.

The mean of a discrete random variable is its weighted average. Generally, every value of X is weighted by its probability.

Relationship to other Variables:

  • Discrete variable – where the value is obtained by counting instances.
  • Continuous variable – where the value is obtained by measuring the properties of instances. 
  • Continuous random variable – where X takes all values in a given interval of possible numbers.
  • Random variable - value is the numerical outcome of a random action.