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Standard deviation

The standard deviation of the distribution is a characteristic of the dispersion of this distribution in the space of real numbers. The greater the standard deviation the larger the dispersion:
Ecart type
Blue: Standard deviation = 1/Green: Standard deviation = 3
The exact calculation of the distribution equation of the standard distribution is given by:
Actually, like the average calculation, we rarely know the distribution of the equation but we do have a series of values. We therefore calculate an approximation of the standard deviation by calculating:
  • n : total number of values