Learn about Variance — part I

Naresh Devineni
Jul 30, 2017 · 1 min read

In lesson 24 and lesson 25, we learned that the expected value (E[X]) is a descriptive quantity of the average (center) of a random variable X with a probability distribution function f(x). In the same way, a measure of the variability, i.e. deviation from the center, of the random variable is the variance V[X].

It is defined as the expected value of the squared deviation from the average.

Naresh Devineni

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Naresh Devineni is an Associate Professor in the Department of Civil Engineering at The City University of New York’s City College. http://nareshdevineni.com

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