Glossary
Six Sigma statistics terminology — concise definitions with formulas, cross-references, and module context.
7 terms
Descriptive Statistics
Kurtosis
Measure of the heaviness of the tails of a distribution relative to the normal.
Mean (Arithmetic Mean)
Sum of all values divided by their count — the most common measure of central tendency.
Median
Middle value of a sorted dataset — the 50 % value.
Range
Difference between the largest and smallest value — the simplest measure of dispersion.
Skewness
Measure of the asymmetry of a distribution about its mean.
Standard Deviation
Square root of the variance — measure of dispersion in the original units of the data.
Variance
Mean squared deviation of values from the mean — a measure of dispersion in a dataset.