For a random variable X,the mean value of the squared deviations of its values from their expected value is called its ____________.
A)Standard deviation
B)Mean
C)Probability
D)Variance

Question

Quizplus · Accepted Answer

The mean value of the squared deviations of its values from their expected value is called the variance of the random variable. It is denoted by σ^2 or Var(X) and is the measure of the spread of the distribution of X. The standard deviation (choice A) is the square root of the variance, while the mean (choice B) is simply the expected value of X. Probability (choice C) is a measure of the likelihood of an event occurring and is not directly related to the variance of X.

For a Random Variable X,the Mean Value of the Squared