An Improved Quantize-Quantize Plot for Normality Test

  • Published : 1998.04.01


A new graphical method, named transformed quantize-quantile (TQQ), of a quantize-quantile (Q-Q) Plot is developed for the detection of deviations from the normal distribution. It will be shown that TQQ is helpful for detecting patterns of how points depart from normality. TQQ characteristics of the various kinds of representations are illustrated by a generated sample from a composite of a normal distribution and a clinical example for TQQ is constructed and explained.



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