Monitoring mean and variability by Gini chart for skew-normal distributed data

Document Type : Article


Department of Statistics, Faculty of Mathematics and Computer, Shahid Bahonar University of Kerman, Kerman, Iran


In order to monitor mean and variability of a process, the Gini control
charts based on the skew-normally distributed random samples is proposed. Through
comparing the false alarm rates of current scheme with those of existing mean and
dispersion control charts, it is found out that the design structure of Gini chart can
improve over other classic schemes based on assumption of skew-normal distribution
for the data. Moreover, the superiority of the Gini chart is studied by comparing
the discriminatory power curves of the skew-normal distribution with some existing
control charts. Simulated studies and a real data example illustrate the usefulness of
the proposed approach.


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