Definition of Variance (Statistics and Mathematics)

At the behest of the theory of probability, which is that branch within the math which focuses on the study of those random phenomena, that is, those whose result is not predictable, the variance of a random variable is a measure of variability or dispersion that will indicate precisely the variation of a distribution, distinguishing through a value if the various scores of a variable are far from the mean. The higher the value, the greater the variability, and the lower the value, the more homogeneous the measurement..

The concept is especially used in the statistics where it serves to identify the mean of the squared deviations of a variable from character random, taking into consideration the mean value of it.

The English scientist Sir Ronald Aylmer Fisher, responsible for its coinage

The English scientist Sir Ronald Aylmer Fisher was responsible for the creation of the concept in the first decade of the last century.
Would be in a station agricultural where they would begin their studies and analysis of variance. He had to undertake the study of a long period of cultivated crops and then in that task the concept arises.

Aylmer has been considered the father of modern statistics and a genius in the field and in many others for the contributions he made in this regard.
He was awarded many honors and the important title of Sir.

The analyzes of variance are a series of statistical models plus the procedures associated and where the variance will appear in different components.

Generally, hand in hand with the concept of variance, another associated appears, that of the standard or typical deviation that represents the magnitude of dispersion of those ratio and interval variables. This concept is also widely used at the behest of statistics, in the descriptive field, and to calculate it, it is necessary to start from the variance and perform the analysis based on it. calculation of the square root.

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