Mean, variation, standard distribution
Definitions
These three concepts are the basics of the following topics, therefore it is very important to understand them.
- Mean : The mean usually refers either to the expected value of a random variable or to the arithmetic average of a set of data
- Variance: A measure of variability defined as the expected value of the square of the random variable around its mean
- Standard Deviation: The positive square root of the variance. The standard deviation is the most widely used measure of variability.