Anxiety can often make these related conditions worse, so talk with a mental health care professional if anxiety begins to interfere on a daily basis.
In probability theory and statistics, the variance of a random variable is a measure of its statistical dispersion, indicating how far from the expected value its values typically are. The variance of a real-valued random variable is its second central moment, and it also happens to be its second cumulant.
The variance for a discrete variable made up of n observations is defined as: The standard deviation for a discrete variable made up of n observations is the positive square root of the variance and is defined as: Use this step-by-step approach to find the standard deviation for a discrete variable. Calculate the mean.