THE POWER OF X-CHART IN PRESENCE OF DATA CORRELATION
Keywords:
Control Chart, Correlation, Power of X-Chart.Abstract
A fundamental assumption in the development of X control chart is that the underlying distribution of the quality characteristic is normal and the process data is normally distributed. However we may have certain situations where the assumption of independence and normality are either fully or partially violated. In this paper an attempt has been made to examine the power of X chart when the assumption of independence of the data is violated. Expressions for the power of X-chart are derived for different values of correlation coefficient.
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