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Create a Data Set with Outliers

The detection of outliers can be quite important, and cumbersome. To gain experience in detecting outliers, you should design 2 data sets exhibiting the following features:

data set 1 700 to 1500 data points, normally distributed, no special measures against outliers taken (use the function "gauss" of the DataLab command Math/Transformation/Single Formula to create the data set)
data set 2 approx. 1000 data points, skewed to the right (hint: use squared data of a normal distribution with a zero mean to create the skewed data). Change 2 values of the data set such that one of these values falls outside the +/-2.5 sigma range, but within the +/-4 sigma range, and the other falls outside the +/-4 sigma range.

Apply the variance/iqr outlier test of DataLab and report the list of outliers.

Please answer the following questions:

You may now go directly to the in order to experiment with the data.

Last Update: 2005-Jul-16