H-Spread
The difference H_2-H_1, where H_1 and H_2 are hinges. It is the same as the interquartile range for N=5, 9, 13, ... points.
See also
Hinge, Interquartile Range, StepExplore with Wolfram|Alpha
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References
Tukey, J. W. Exploratory Data Analysis. Reading, MA: Addison-Wesley, p. 44, 1977.Referenced on Wolfram|Alpha
H-SpreadCite this as:
Weisstein, Eric W. "H-Spread." From MathWorld--A Wolfram Resource. https://mathworld.wolfram.com/H-Spread.html