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(outliers sequence #:coef)procedure

Identifies outliers using Tukey's method. Values beyond #:coef times the IQR from Q1/Q3 are considered outliers. Returns two values: a list of outlier values and a list of non-outlier values (clean sequence). The #:coef parameter defaults to 1.5 (standard outliers); use 3.0 for extreme outliers.

> (outliers '(10 12 14 15 16 18 20 100) #:coef 1.5)
(100)
(10 12 14 15 16 18 20)
; 2 values