(Faculty of Humanities and Sciences, SLIIT, 2022-09-15) Amaratunga, D
Reference ranges and control limits are used in
many settings – for example, to assess a
person’s health or to monitor the stability of a
manufacturing process. Such ranges are
established based on a baseline sample of what
is considered normal data, but it is not possible
to always avoid a few outliers being present
even in this sample. If, as is common, the range
is calculated using statistics, such as the mean
and standard deviation, which could be
influenced by outliers, then the use of such a
range could adversely affect the decisions
made. This can be avoided by constructing the
reference range using statistics that are
resistant to outliers. In this paper, we
demonstrate the superior performance of such
an approach.
