Читать книгу Lean Six Sigma For Dummies - Martin Brenig-Jones - Страница 21

The standard deviation is a measure that reveals the amount of variation. It is represented as the lower-case Greek letter (sigma) and describes the average dispersal of the individual data points from their overall average. Why is this helpful? The smaller the standard deviation value is, the less variation there is. Conversely, the larger the value, the more variation. By understanding the amount and type of variation in our results, we can get closer to understanding the “behavior” of the process (or the thing we are measuring) and what this means for customers.