InterquartileRange
InterquartileRange[data] gives the difference between the upper and lower quartiles q&^3/4-q&^1/4 for the elements in data.
InterquartileRange[data,{{a,b},{c,d}}] uses the quantile definition specified by parameters a, b, c, d.
InterquartileRange[dist] gives the difference between the upper and lower quartiles q3/4-q1/4 for the distribution dist.
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