Quartiles
Quartiles[data] gives the {q&^1/4,q&^2/4,q&^3/4} quantile estimates of the elements in data.
Quartiles[data,{{a,b},{c,d}}] uses the quantile definition specified by parameters a, b, c, d.
Quartiles[dist] gives the {q1/4,q2/4,q3/4} quantiles of the distribution dist.
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