This macro calculates the median absolute deviation of a data set.
Be sure that Minitab knows where to find your downloaded macro. Choose . Under Macro location browse to the location where you save macro files.
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Suppose your data are in C1. To run the macro, choose and type:
%MEDABSDV C1
Click Run.
Formula
MEDABSDV = bn*1.4826*MEDIAN{abs[C - MEDIAN(C)]}
Where 1.4826 makes the expected value of MEDABSDV = STDEV(Normal population) and bn is a finite sample corrrection factor.
Reference
C. Croux and P. J. Rousseeuw, Time-efficient Algorithms for Two Highly Robust Estimators of Scale, Computational Statistics, v. 2, 411-428, (1992).