The variance of a discrete random variable is always greater than or equal to zero.

Question

Quizplus · Accepted Answer

The variance of a discrete random variable is defined as the sum of the squared differences between each possible value and the expected value, multiplied by the probability of that value occurring. Since probabilities are always non-negative, and squared differences are always non-negative, the variance is always greater than or equal to zero.

The Variance of a Discrete Random Variable Is Always Greater