Enter a series of values to compute the range R = max - min, a quick measure of the spread of a data set.
| Item | Formula / Note | Source / Standard |
|---|---|---|
| Range | R = x_max - x_min | ISO 3534-1:2006, Statistics - Vocabulary and symbols |
| Expected range | E[R] = d2 · sigma, where d2 is the control-chart constant for sample size n | Montgomery DC, Introduction to Statistical Quality Control (7th ed.), Wiley |
| Estimating sigma from R | sigma-hat = R / d2 | Montgomery DC, Introduction to Statistical Quality Control (7th ed.) |
| Limitation | Uses only two order statistics; highly sensitive to outliers and inefficient for large n | NIST/SEMATECH e-Handbook of Statistical Methods §1.3.5.1 |